claw-code/rust/crates/tools/src/lib.rs

use std::collections::BTreeSet;
use std::time::{Duration, Instant};

use reqwest::blocking::Client;
use runtime::{
    edit_file, execute_bash, glob_search, grep_search, read_file, write_file, BashCommandInput,
    GrepSearchInput,
};
use serde::{Deserialize, Serialize};
use serde_json::{json, Value};

#[derive(Debug, Clone, PartialEq, Eq)]
pub struct ToolManifestEntry {
    pub name: String,
    pub source: ToolSource,
}

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum ToolSource {
    Base,
    Conditional,
}

#[derive(Debug, Clone, Default, PartialEq, Eq)]
pub struct ToolRegistry {
    entries: Vec<ToolManifestEntry>,
}

impl ToolRegistry {
    #[must_use]
    pub fn new(entries: Vec<ToolManifestEntry>) -> Self {
        Self { entries }
    }

    #[must_use]
    pub fn entries(&self) -> &[ToolManifestEntry] {
        &self.entries
    }
}

#[derive(Debug, Clone, PartialEq, Eq)]
pub struct ToolSpec {
    pub name: &'static str,
    pub description: &'static str,
    pub input_schema: Value,
}

#[must_use]
pub fn mvp_tool_specs() -> Vec<ToolSpec> {
    vec![
        ToolSpec {
            name: "bash",
            description: "Execute a shell command in the current workspace.",
            input_schema: json!({
                "type": "object",
                "properties": {
                    "command": { "type": "string" },
                    "timeout": { "type": "integer", "minimum": 1 },
                    "description": { "type": "string" },
                    "run_in_background": { "type": "boolean" },
                    "dangerouslyDisableSandbox": { "type": "boolean" }
                },
                "required": ["command"],
                "additionalProperties": false
            }),
        },
        ToolSpec {
            name: "read_file",
            description: "Read a text file from the workspace.",
            input_schema: json!({
                "type": "object",
                "properties": {
                    "path": { "type": "string" },
                    "offset": { "type": "integer", "minimum": 0 },
                    "limit": { "type": "integer", "minimum": 1 }
                },
                "required": ["path"],
                "additionalProperties": false
            }),
        },
        ToolSpec {
            name: "write_file",
            description: "Write a text file in the workspace.",
            input_schema: json!({
                "type": "object",
                "properties": {
                    "path": { "type": "string" },
                    "content": { "type": "string" }
                },
                "required": ["path", "content"],
                "additionalProperties": false
            }),
        },
        ToolSpec {
            name: "edit_file",
            description: "Replace text in a workspace file.",
            input_schema: json!({
                "type": "object",
                "properties": {
                    "path": { "type": "string" },
                    "old_string": { "type": "string" },
                    "new_string": { "type": "string" },
                    "replace_all": { "type": "boolean" }
                },
                "required": ["path", "old_string", "new_string"],
                "additionalProperties": false
            }),
        },
        ToolSpec {
            name: "glob_search",
            description: "Find files by glob pattern.",
            input_schema: json!({
                "type": "object",
                "properties": {
                    "pattern": { "type": "string" },
                    "path": { "type": "string" }
                },
                "required": ["pattern"],
                "additionalProperties": false
            }),
        },
        ToolSpec {
            name: "grep_search",
            description: "Search file contents with a regex pattern.",
            input_schema: json!({
                "type": "object",
                "properties": {
                    "pattern": { "type": "string" },
                    "path": { "type": "string" },
                    "glob": { "type": "string" },
                    "output_mode": { "type": "string" },
                    "-B": { "type": "integer", "minimum": 0 },
                    "-A": { "type": "integer", "minimum": 0 },
                    "-C": { "type": "integer", "minimum": 0 },
                    "context": { "type": "integer", "minimum": 0 },
                    "-n": { "type": "boolean" },
                    "-i": { "type": "boolean" },
                    "type": { "type": "string" },
                    "head_limit": { "type": "integer", "minimum": 1 },
                    "offset": { "type": "integer", "minimum": 0 },
                    "multiline": { "type": "boolean" }
                },
                "required": ["pattern"],
                "additionalProperties": false
            }),
        },
        ToolSpec {
            name: "WebFetch",
            description:
                "Fetch a URL, convert it into readable text, and answer a prompt about it.",
            input_schema: json!({
                "type": "object",
                "properties": {
                    "url": { "type": "string", "format": "uri" },
                    "prompt": { "type": "string" }
                },
                "required": ["url", "prompt"],
                "additionalProperties": false
            }),
        },
        ToolSpec {
            name: "WebSearch",
            description: "Search the web for current information and return cited results.",
            input_schema: json!({
                "type": "object",
                "properties": {
                    "query": { "type": "string", "minLength": 2 },
                    "allowed_domains": {
                        "type": "array",
                        "items": { "type": "string" }
                    },
                    "blocked_domains": {
                        "type": "array",
                        "items": { "type": "string" }
                    }
                },
                "required": ["query"],
                "additionalProperties": false
            }),
        },
        ToolSpec {
            name: "TodoWrite",
            description: "Update the structured task list for the current session.",
            input_schema: json!({
                "type": "object",
                "properties": {
                    "todos": {
                        "type": "array",
                        "items": {
                            "type": "object",
                            "properties": {
                                "content": { "type": "string" },
                                "activeForm": { "type": "string" },
                                "status": {
                                    "type": "string",
                                    "enum": ["pending", "in_progress", "completed"]
                                }
                            },
                            "required": ["content", "activeForm", "status"],
                            "additionalProperties": false
                        }
                    }
                },
                "required": ["todos"],
                "additionalProperties": false
            }),
        },
        ToolSpec {
            name: "Skill",
            description: "Load a local skill definition and its instructions.",
            input_schema: json!({
                "type": "object",
                "properties": {
                    "skill": { "type": "string" },
                    "args": { "type": "string" }
                },
                "required": ["skill"],
                "additionalProperties": false
            }),
        },
        ToolSpec {
            name: "Agent",
            description: "Launch a specialized agent task and persist its handoff metadata.",
            input_schema: json!({
                "type": "object",
                "properties": {
                    "description": { "type": "string" },
                    "prompt": { "type": "string" },
                    "subagent_type": { "type": "string" },
                    "name": { "type": "string" },
                    "model": { "type": "string" }
                },
                "required": ["description", "prompt"],
                "additionalProperties": false
            }),
        },
        ToolSpec {
            name: "ToolSearch",
            description: "Search for deferred or specialized tools by exact name or keywords.",
            input_schema: json!({
                "type": "object",
                "properties": {
                    "query": { "type": "string" },
                    "max_results": { "type": "integer", "minimum": 1 }
                },
                "required": ["query"],
                "additionalProperties": false
            }),
        },
        ToolSpec {
            name: "NotebookEdit",
            description: "Replace, insert, or delete a cell in a Jupyter notebook.",
            input_schema: json!({
                "type": "object",
                "properties": {
                    "notebook_path": { "type": "string" },
                    "cell_id": { "type": "string" },
                    "new_source": { "type": "string" },
                    "cell_type": { "type": "string", "enum": ["code", "markdown"] },
                    "edit_mode": { "type": "string", "enum": ["replace", "insert", "delete"] }
                },
                "required": ["notebook_path"],
                "additionalProperties": false
            }),
        },
        ToolSpec {
            name: "Sleep",
            description: "Wait for a specified duration without holding a shell process.",
            input_schema: json!({
                "type": "object",
                "properties": {
                    "duration_ms": { "type": "integer", "minimum": 0 }
                },
                "required": ["duration_ms"],
                "additionalProperties": false
            }),
        },
        ToolSpec {
            name: "PowerShell",
            description: "Execute a PowerShell command with optional timeout.",
            input_schema: json!({
                "type": "object",
                "properties": {
                    "command": { "type": "string" },
                    "timeout": { "type": "integer", "minimum": 1 },
                    "description": { "type": "string" },
                    "run_in_background": { "type": "boolean" }
                },
                "required": ["command"],
                "additionalProperties": false
            }),
        },
    ]
}

pub fn execute_tool(name: &str, input: &Value) -> Result<String, String> {
    match name {
        "bash" => from_value::<BashCommandInput>(input).and_then(run_bash),
        "read_file" => from_value::<ReadFileInput>(input).and_then(run_read_file),
        "write_file" => from_value::<WriteFileInput>(input).and_then(run_write_file),
        "edit_file" => from_value::<EditFileInput>(input).and_then(run_edit_file),
        "glob_search" => from_value::<GlobSearchInputValue>(input).and_then(run_glob_search),
        "grep_search" => from_value::<GrepSearchInput>(input).and_then(run_grep_search),
        "WebFetch" => from_value::<WebFetchInput>(input).and_then(run_web_fetch),
        "WebSearch" => from_value::<WebSearchInput>(input).and_then(run_web_search),
        "TodoWrite" => from_value::<TodoWriteInput>(input).and_then(run_todo_write),
        "Skill" => from_value::<SkillInput>(input).and_then(run_skill),
        "Agent" => from_value::<AgentInput>(input).and_then(run_agent),
        "ToolSearch" => from_value::<ToolSearchInput>(input).and_then(run_tool_search),
        "NotebookEdit" => from_value::<NotebookEditInput>(input).and_then(run_notebook_edit),
        "Sleep" => from_value::<SleepInput>(input).and_then(run_sleep),
        "PowerShell" => from_value::<PowerShellInput>(input).and_then(run_powershell),
        _ => Err(format!("unsupported tool: {name}")),
    }
}

fn from_value<T: for<'de> Deserialize<'de>>(input: &Value) -> Result<T, String> {
    serde_json::from_value(input.clone()).map_err(|error| error.to_string())
}

fn run_bash(input: BashCommandInput) -> Result<String, String> {
    serde_json::to_string_pretty(&execute_bash(input).map_err(|error| error.to_string())?)
        .map_err(|error| error.to_string())
}

fn run_read_file(input: ReadFileInput) -> Result<String, String> {
    to_pretty_json(read_file(&input.path, input.offset, input.limit).map_err(io_to_string)?)
}

fn run_write_file(input: WriteFileInput) -> Result<String, String> {
    to_pretty_json(write_file(&input.path, &input.content).map_err(io_to_string)?)
}

fn run_edit_file(input: EditFileInput) -> Result<String, String> {
    to_pretty_json(
        edit_file(
            &input.path,
            &input.old_string,
            &input.new_string,
            input.replace_all.unwrap_or(false),
        )
        .map_err(io_to_string)?,
    )
}

fn run_glob_search(input: GlobSearchInputValue) -> Result<String, String> {
    to_pretty_json(glob_search(&input.pattern, input.path.as_deref()).map_err(io_to_string)?)
}

fn run_grep_search(input: GrepSearchInput) -> Result<String, String> {
    to_pretty_json(grep_search(&input).map_err(io_to_string)?)
}

fn run_web_fetch(input: WebFetchInput) -> Result<String, String> {
    to_pretty_json(execute_web_fetch(&input)?)
}

fn run_web_search(input: WebSearchInput) -> Result<String, String> {
    to_pretty_json(execute_web_search(&input)?)
}

fn run_todo_write(input: TodoWriteInput) -> Result<String, String> {
    to_pretty_json(execute_todo_write(input)?)
}

fn run_skill(input: SkillInput) -> Result<String, String> {
    to_pretty_json(execute_skill(input)?)
}

fn run_agent(input: AgentInput) -> Result<String, String> {
    to_pretty_json(execute_agent(input)?)
}

fn run_tool_search(input: ToolSearchInput) -> Result<String, String> {
    to_pretty_json(execute_tool_search(input))
}

fn run_notebook_edit(input: NotebookEditInput) -> Result<String, String> {
    to_pretty_json(execute_notebook_edit(input)?)
}

fn run_sleep(input: SleepInput) -> Result<String, String> {
    to_pretty_json(execute_sleep(input))
}

fn run_powershell(input: PowerShellInput) -> Result<String, String> {
    to_pretty_json(execute_powershell(input).map_err(|error| error.to_string())?)
}

fn to_pretty_json<T: serde::Serialize>(value: T) -> Result<String, String> {
    serde_json::to_string_pretty(&value).map_err(|error| error.to_string())
}

fn io_to_string(error: std::io::Error) -> String {
    error.to_string()
}

#[derive(Debug, Deserialize)]
struct ReadFileInput {
    path: String,
    offset: Option<usize>,
    limit: Option<usize>,
}

#[derive(Debug, Deserialize)]
struct WriteFileInput {
    path: String,
    content: String,
}

#[derive(Debug, Deserialize)]
struct EditFileInput {
    path: String,
    old_string: String,
    new_string: String,
    replace_all: Option<bool>,
}

#[derive(Debug, Deserialize)]
struct GlobSearchInputValue {
    pattern: String,
    path: Option<String>,
}

#[derive(Debug, Deserialize)]
struct WebFetchInput {
    url: String,
    prompt: String,
}

#[derive(Debug, Deserialize)]
struct WebSearchInput {
    query: String,
    allowed_domains: Option<Vec<String>>,
    blocked_domains: Option<Vec<String>>,
}

#[derive(Debug, Deserialize)]
struct TodoWriteInput {
    todos: Vec<TodoItem>,
}

#[derive(Debug, Deserialize, Serialize, Clone, PartialEq, Eq)]
struct TodoItem {
    content: String,
    #[serde(rename = "activeForm")]
    active_form: String,
    status: TodoStatus,
}

#[derive(Debug, Deserialize, Serialize, Clone, PartialEq, Eq)]
#[serde(rename_all = "snake_case")]
enum TodoStatus {
    Pending,
    InProgress,
    Completed,
}

#[derive(Debug, Deserialize)]
struct SkillInput {
    skill: String,
    args: Option<String>,
}

#[derive(Debug, Deserialize)]
struct AgentInput {
    description: String,
    prompt: String,
    subagent_type: Option<String>,
    name: Option<String>,
    model: Option<String>,
}

#[derive(Debug, Deserialize)]
struct ToolSearchInput {
    query: String,
    max_results: Option<usize>,
}

#[derive(Debug, Deserialize)]
struct NotebookEditInput {
    notebook_path: String,
    cell_id: Option<String>,
    new_source: Option<String>,
    cell_type: Option<NotebookCellType>,
    edit_mode: Option<NotebookEditMode>,
}

#[derive(Debug, Deserialize, Serialize, Clone, Copy, PartialEq, Eq)]
#[serde(rename_all = "lowercase")]
enum NotebookCellType {
    Code,
    Markdown,
}

#[derive(Debug, Deserialize, Serialize, Clone, Copy, PartialEq, Eq)]
#[serde(rename_all = "lowercase")]
enum NotebookEditMode {
    Replace,
    Insert,
    Delete,
}

#[derive(Debug, Deserialize)]
struct SleepInput {
    duration_ms: u64,
}

#[derive(Debug, Deserialize)]
struct PowerShellInput {
    command: String,
    timeout: Option<u64>,
    description: Option<String>,
    run_in_background: Option<bool>,
}

#[derive(Debug, Serialize)]
struct WebFetchOutput {
    bytes: usize,
    code: u16,
    #[serde(rename = "codeText")]
    code_text: String,
    result: String,
    #[serde(rename = "durationMs")]
    duration_ms: u128,
    url: String,
}

#[derive(Debug, Serialize)]
struct WebSearchOutput {
    query: String,
    results: Vec<WebSearchResultItem>,
    #[serde(rename = "durationSeconds")]
    duration_seconds: f64,
}

#[derive(Debug, Serialize)]
struct TodoWriteOutput {
    #[serde(rename = "oldTodos")]
    old_todos: Vec<TodoItem>,
    #[serde(rename = "newTodos")]
    new_todos: Vec<TodoItem>,
    #[serde(rename = "verificationNudgeNeeded")]
    verification_nudge_needed: Option<bool>,
}

#[derive(Debug, Serialize)]
struct SkillOutput {
    skill: String,
    path: String,
    args: Option<String>,
    description: Option<String>,
    prompt: String,
}

#[derive(Debug, Serialize, Deserialize)]
struct AgentOutput {
    #[serde(rename = "agentId")]
    agent_id: String,
    name: String,
    description: String,
    #[serde(rename = "subagentType")]
    subagent_type: Option<String>,
    model: Option<String>,
    status: String,
    #[serde(rename = "outputFile")]
    output_file: String,
    #[serde(rename = "manifestFile")]
    manifest_file: String,
    #[serde(rename = "createdAt")]
    created_at: String,
}

#[derive(Debug, Serialize)]
struct ToolSearchOutput {
    matches: Vec<String>,
    query: String,
    normalized_query: String,
    #[serde(rename = "total_deferred_tools")]
    total_deferred_tools: usize,
    #[serde(rename = "pending_mcp_servers")]
    pending_mcp_servers: Option<Vec<String>>,
}

#[derive(Debug, Serialize)]
struct NotebookEditOutput {
    new_source: String,
    cell_id: Option<String>,
    cell_type: Option<NotebookCellType>,
    language: String,
    edit_mode: String,
    error: Option<String>,
    notebook_path: String,
    original_file: String,
    updated_file: String,
}

#[derive(Debug, Serialize)]
struct SleepOutput {
    duration_ms: u64,
    message: String,
}

#[derive(Debug, Serialize)]
#[serde(untagged)]
enum WebSearchResultItem {
    SearchResult {
        tool_use_id: String,
        content: Vec<SearchHit>,
    },
    Commentary(String),
}

#[derive(Debug, Serialize)]
struct SearchHit {
    title: String,
    url: String,
}

fn execute_web_fetch(input: &WebFetchInput) -> Result<WebFetchOutput, String> {
    let started = Instant::now();
    let client = build_http_client()?;
    let request_url = normalize_fetch_url(&input.url)?;
    let response = client
        .get(request_url.clone())
        .send()
        .map_err(|error| error.to_string())?;

    let status = response.status();
    let final_url = response.url().to_string();
    let code = status.as_u16();
    let code_text = status.canonical_reason().unwrap_or("Unknown").to_string();
    let content_type = response
        .headers()
        .get(reqwest::header::CONTENT_TYPE)
        .and_then(|value| value.to_str().ok())
        .unwrap_or_default()
        .to_string();
    let body = response.text().map_err(|error| error.to_string())?;
    let bytes = body.len();
    let normalized = normalize_fetched_content(&body, &content_type);
    let result = summarize_web_fetch(&final_url, &input.prompt, &normalized);

    Ok(WebFetchOutput {
        bytes,
        code,
        code_text,
        result,
        duration_ms: started.elapsed().as_millis(),
        url: final_url,
    })
}

fn execute_web_search(input: &WebSearchInput) -> Result<WebSearchOutput, String> {
    let started = Instant::now();
    let client = build_http_client()?;
    let search_url = build_search_url(&input.query)?;
    let response = client
        .get(search_url)
        .send()
        .map_err(|error| error.to_string())?;

    let final_url = response.url().clone();
    let html = response.text().map_err(|error| error.to_string())?;
    let mut hits = extract_search_hits(&html);

    if hits.is_empty() && final_url.host_str().is_some() {
        hits = extract_search_hits_from_generic_links(&html);
    }

    if let Some(allowed) = input.allowed_domains.as_ref() {
        hits.retain(|hit| host_matches_list(&hit.url, allowed));
    }
    if let Some(blocked) = input.blocked_domains.as_ref() {
        hits.retain(|hit| !host_matches_list(&hit.url, blocked));
    }

    dedupe_hits(&mut hits);
    hits.truncate(8);

    let summary = if hits.is_empty() {
        format!("No web search results matched the query {:?}.", input.query)
    } else {
        let rendered_hits = hits
            .iter()
            .map(|hit| format!("- [{}]({})", hit.title, hit.url))
            .collect::<Vec<_>>()
            .join("\n");
        format!(
            "Search results for {:?}. Include a Sources section in the final answer.\n{}",
            input.query, rendered_hits
        )
    };

    Ok(WebSearchOutput {
        query: input.query.clone(),
        results: vec![
            WebSearchResultItem::Commentary(summary),
            WebSearchResultItem::SearchResult {
                tool_use_id: String::from("web_search_1"),
                content: hits,
            },
        ],
        duration_seconds: started.elapsed().as_secs_f64(),
    })
}

fn build_http_client() -> Result<Client, String> {
    Client::builder()
        .timeout(Duration::from_secs(20))
        .redirect(reqwest::redirect::Policy::limited(10))
        .user_agent("clawd-rust-tools/0.1")
        .build()
        .map_err(|error| error.to_string())
}

fn normalize_fetch_url(url: &str) -> Result<String, String> {
    let parsed = reqwest::Url::parse(url).map_err(|error| error.to_string())?;
    if parsed.scheme() == "http" {
        let host = parsed.host_str().unwrap_or_default();
        if host != "localhost" && host != "127.0.0.1" && host != "::1" {
            let mut upgraded = parsed;
            upgraded
                .set_scheme("https")
                .map_err(|_| String::from("failed to upgrade URL to https"))?;
            return Ok(upgraded.to_string());
        }
    }
    Ok(parsed.to_string())
}

fn build_search_url(query: &str) -> Result<reqwest::Url, String> {
    if let Ok(base) = std::env::var("CLAWD_WEB_SEARCH_BASE_URL") {
        let mut url = reqwest::Url::parse(&base).map_err(|error| error.to_string())?;
        url.query_pairs_mut().append_pair("q", query);
        return Ok(url);
    }

    let mut url = reqwest::Url::parse("https://html.duckduckgo.com/html/")
        .map_err(|error| error.to_string())?;
    url.query_pairs_mut().append_pair("q", query);
    Ok(url)
}

fn normalize_fetched_content(body: &str, content_type: &str) -> String {
    if content_type.contains("html") {
        html_to_text(body)
    } else {
        body.trim().to_string()
    }
}

fn summarize_web_fetch(url: &str, prompt: &str, content: &str) -> String {
    let lower_prompt = prompt.to_lowercase();
    let compact = collapse_whitespace(content);

    let detail = if lower_prompt.contains("title") {
        extract_title(content)
            .map(|title| format!("Title: {title}"))
            .unwrap_or_else(|| preview_text(&compact, 600))
    } else if lower_prompt.contains("summary") || lower_prompt.contains("summarize") {
        preview_text(&compact, 900)
    } else {
        let preview = preview_text(&compact, 900);
        format!("Prompt: {prompt}\nContent preview:\n{preview}")
    };

    format!("Fetched {url}\n{detail}")
}

fn extract_title(content: &str) -> Option<String> {
    for line in content.lines() {
        let trimmed = line.trim();
        if !trimmed.is_empty() {
            return Some(trimmed.to_string());
        }
    }
    None
}

fn html_to_text(html: &str) -> String {
    let mut text = String::with_capacity(html.len());
    let mut in_tag = false;
    let mut previous_was_space = false;

    for ch in html.chars() {
        match ch {
            '<' => in_tag = true,
            '>' => in_tag = false,
            _ if in_tag => {}
            '&' => {
                text.push('&');
                previous_was_space = false;
            }
            ch if ch.is_whitespace() => {
                if !previous_was_space {
                    text.push(' ');
                    previous_was_space = true;
                }
            }
            _ => {
                text.push(ch);
                previous_was_space = false;
            }
        }
    }

    collapse_whitespace(&decode_html_entities(&text))
}

fn decode_html_entities(input: &str) -> String {
    input
        .replace("&amp;", "&")
        .replace("&lt;", "<")
        .replace("&gt;", ">")
        .replace("&quot;", "\"")
        .replace("&#39;", "'")
        .replace("&nbsp;", " ")
}

fn collapse_whitespace(input: &str) -> String {
    input.split_whitespace().collect::<Vec<_>>().join(" ")
}

fn preview_text(input: &str, max_chars: usize) -> String {
    if input.chars().count() <= max_chars {
        return input.to_string();
    }
    let shortened = input.chars().take(max_chars).collect::<String>();
    format!("{}…", shortened.trim_end())
}

fn extract_search_hits(html: &str) -> Vec<SearchHit> {
    let mut hits = Vec::new();
    let mut remaining = html;

    while let Some(anchor_start) = remaining.find("result__a") {
        let after_class = &remaining[anchor_start..];
        let Some(href_idx) = after_class.find("href=") else {
            remaining = &after_class[1..];
            continue;
        };
        let href_slice = &after_class[href_idx + 5..];
        let Some((url, rest)) = extract_quoted_value(href_slice) else {
            remaining = &after_class[1..];
            continue;
        };
        let Some(close_tag_idx) = rest.find('>') else {
            remaining = &after_class[1..];
            continue;
        };
        let after_tag = &rest[close_tag_idx + 1..];
        let Some(end_anchor_idx) = after_tag.find("</a>") else {
            remaining = &after_tag[1..];
            continue;
        };
        let title = html_to_text(&after_tag[..end_anchor_idx]);
        if let Some(decoded_url) = decode_duckduckgo_redirect(&url) {
            hits.push(SearchHit {
                title: title.trim().to_string(),
                url: decoded_url,
            });
        }
        remaining = &after_tag[end_anchor_idx + 4..];
    }

    hits
}

fn extract_search_hits_from_generic_links(html: &str) -> Vec<SearchHit> {
    let mut hits = Vec::new();
    let mut remaining = html;

    while let Some(anchor_start) = remaining.find("<a") {
        let after_anchor = &remaining[anchor_start..];
        let Some(href_idx) = after_anchor.find("href=") else {
            remaining = &after_anchor[2..];
            continue;
        };
        let href_slice = &after_anchor[href_idx + 5..];
        let Some((url, rest)) = extract_quoted_value(href_slice) else {
            remaining = &after_anchor[2..];
            continue;
        };
        let Some(close_tag_idx) = rest.find('>') else {
            remaining = &after_anchor[2..];
            continue;
        };
        let after_tag = &rest[close_tag_idx + 1..];
        let Some(end_anchor_idx) = after_tag.find("</a>") else {
            remaining = &after_anchor[2..];
            continue;
        };
        let title = html_to_text(&after_tag[..end_anchor_idx]);
        if title.trim().is_empty() {
            remaining = &after_tag[end_anchor_idx + 4..];
            continue;
        }
        let decoded_url = decode_duckduckgo_redirect(&url).unwrap_or(url);
        if decoded_url.starts_with("http://") || decoded_url.starts_with("https://") {
            hits.push(SearchHit {
                title: title.trim().to_string(),
                url: decoded_url,
            });
        }
        remaining = &after_tag[end_anchor_idx + 4..];
    }

    hits
}

fn extract_quoted_value(input: &str) -> Option<(String, &str)> {
    let quote = input.chars().next()?;
    if quote != '"' && quote != '\'' {
        return None;
    }
    let rest = &input[quote.len_utf8()..];
    let end = rest.find(quote)?;
    Some((rest[..end].to_string(), &rest[end + quote.len_utf8()..]))
}

fn decode_duckduckgo_redirect(url: &str) -> Option<String> {
    if url.starts_with("http://") || url.starts_with("https://") {
        return Some(html_entity_decode_url(url));
    }

    let joined = if url.starts_with("//") {
        format!("https:{url}")
    } else if url.starts_with('/') {
        format!("https://duckduckgo.com{url}")
    } else {
        return None;
    };

    let parsed = reqwest::Url::parse(&joined).ok()?;
    if parsed.path() == "/l/" || parsed.path() == "/l" {
        for (key, value) in parsed.query_pairs() {
            if key == "uddg" {
                return Some(html_entity_decode_url(value.as_ref()));
            }
        }
    }
    Some(joined)
}

fn html_entity_decode_url(url: &str) -> String {
    decode_html_entities(url)
}

fn host_matches_list(url: &str, domains: &[String]) -> bool {
    let Ok(parsed) = reqwest::Url::parse(url) else {
        return false;
    };
    let Some(host) = parsed.host_str() else {
        return false;
    };
    domains.iter().any(|domain| {
        let normalized = domain.trim().trim_start_matches('.');
        host == normalized || host.ends_with(&format!(".{normalized}"))
    })
}

fn dedupe_hits(hits: &mut Vec<SearchHit>) {
    let mut seen = BTreeSet::new();
    hits.retain(|hit| seen.insert(hit.url.clone()));
}

fn execute_todo_write(input: TodoWriteInput) -> Result<TodoWriteOutput, String> {
    validate_todos(&input.todos)?;
    let store_path = todo_store_path()?;
    let old_todos = if store_path.exists() {
        serde_json::from_str::<Vec<TodoItem>>(
            &std::fs::read_to_string(&store_path).map_err(|error| error.to_string())?,
        )
        .map_err(|error| error.to_string())?
    } else {
        Vec::new()
    };

    let all_done = input
        .todos
        .iter()
        .all(|todo| matches!(todo.status, TodoStatus::Completed));
    let persisted = if all_done {
        Vec::new()
    } else {
        input.todos.clone()
    };

    if let Some(parent) = store_path.parent() {
        std::fs::create_dir_all(parent).map_err(|error| error.to_string())?;
    }
    std::fs::write(
        &store_path,
        serde_json::to_string_pretty(&persisted).map_err(|error| error.to_string())?,
    )
    .map_err(|error| error.to_string())?;

    let verification_nudge_needed = (all_done
        && input.todos.len() >= 3
        && !input
            .todos
            .iter()
            .any(|todo| todo.content.to_lowercase().contains("verif")))
    .then_some(true);

    Ok(TodoWriteOutput {
        old_todos,
        new_todos: input.todos,
        verification_nudge_needed,
    })
}

fn execute_skill(input: SkillInput) -> Result<SkillOutput, String> {
    let skill_path = resolve_skill_path(&input.skill)?;
    let prompt = std::fs::read_to_string(&skill_path).map_err(|error| error.to_string())?;
    let description = parse_skill_description(&prompt);

    Ok(SkillOutput {
        skill: input.skill,
        path: skill_path.display().to_string(),
        args: input.args,
        description,
        prompt,
    })
}

fn validate_todos(todos: &[TodoItem]) -> Result<(), String> {
    if todos.is_empty() {
        return Err(String::from("todos must not be empty"));
    }
    let in_progress = todos
        .iter()
        .filter(|todo| matches!(todo.status, TodoStatus::InProgress))
        .count();
    if in_progress > 1 {
        return Err(String::from(
            "exactly zero or one todo items may be in_progress",
        ));
    }
    if todos.iter().any(|todo| todo.content.trim().is_empty()) {
        return Err(String::from("todo content must not be empty"));
    }
    if todos.iter().any(|todo| todo.active_form.trim().is_empty()) {
        return Err(String::from("todo activeForm must not be empty"));
    }
    Ok(())
}

fn todo_store_path() -> Result<std::path::PathBuf, String> {
    if let Ok(path) = std::env::var("CLAWD_TODO_STORE") {
        return Ok(std::path::PathBuf::from(path));
    }
    let cwd = std::env::current_dir().map_err(|error| error.to_string())?;
    Ok(cwd.join(".clawd-todos.json"))
}

fn resolve_skill_path(skill: &str) -> Result<std::path::PathBuf, String> {
    let requested = skill.trim().trim_start_matches('/');
    if requested.is_empty() {
        return Err(String::from("skill must not be empty"));
    }

    let mut candidates = Vec::new();
    if let Ok(codex_home) = std::env::var("CODEX_HOME") {
        candidates.push(std::path::PathBuf::from(codex_home).join("skills"));
    }
    candidates.push(std::path::PathBuf::from("/home/bellman/.codex/skills"));

    for root in candidates {
        let direct = root.join(requested).join("SKILL.md");
        if direct.exists() {
            return Ok(direct);
        }

        if let Ok(entries) = std::fs::read_dir(&root) {
            for entry in entries.flatten() {
                let path = entry.path().join("SKILL.md");
                if !path.exists() {
                    continue;
                }
                if entry
                    .file_name()
                    .to_string_lossy()
                    .eq_ignore_ascii_case(requested)
                {
                    return Ok(path);
                }
            }
        }
    }

    Err(format!("unknown skill: {requested}"))
}

fn execute_agent(input: AgentInput) -> Result<AgentOutput, String> {
    if input.description.trim().is_empty() {
        return Err(String::from("description must not be empty"));
    }
    if input.prompt.trim().is_empty() {
        return Err(String::from("prompt must not be empty"));
    }

    let agent_id = make_agent_id();
    let output_dir = agent_store_dir()?;
    std::fs::create_dir_all(&output_dir).map_err(|error| error.to_string())?;
    let output_file = output_dir.join(format!("{agent_id}.md"));
    let manifest_file = output_dir.join(format!("{agent_id}.json"));
    let normalized_subagent_type = normalize_subagent_type(input.subagent_type.as_deref());
    let agent_name = input
        .name
        .clone()
        .unwrap_or_else(|| slugify_agent_name(&input.description));
    let created_at = iso8601_now();

    let output_contents = format!(
        "# Agent Task

- id: {}
- name: {}
- description: {}
- subagent_type: {}
- created_at: {}

## Prompt

{}
",
        agent_id, agent_name, input.description, normalized_subagent_type, created_at, input.prompt
    );
    std::fs::write(&output_file, output_contents).map_err(|error| error.to_string())?;

    let manifest = AgentOutput {
        agent_id,
        name: agent_name,
        description: input.description,
        subagent_type: Some(normalized_subagent_type),
        model: input.model,
        status: String::from("queued"),
        output_file: output_file.display().to_string(),
        manifest_file: manifest_file.display().to_string(),
        created_at,
    };
    std::fs::write(
        &manifest_file,
        serde_json::to_string_pretty(&manifest).map_err(|error| error.to_string())?,
    )
    .map_err(|error| error.to_string())?;

    Ok(manifest)
}

fn execute_tool_search(input: ToolSearchInput) -> ToolSearchOutput {
    let deferred = deferred_tool_specs();
    let max_results = input.max_results.unwrap_or(5).max(1);
    let query = input.query.trim().to_string();
    let normalized_query = normalize_tool_search_query(&query);
    let matches = search_tool_specs(&query, max_results, &deferred);

    ToolSearchOutput {
        matches,
        query,
        normalized_query,
        total_deferred_tools: deferred.len(),
        pending_mcp_servers: None,
    }
}

fn deferred_tool_specs() -> Vec<ToolSpec> {
    mvp_tool_specs()
        .into_iter()
        .filter(|spec| {
            !matches!(
                spec.name,
                "bash" | "read_file" | "write_file" | "edit_file" | "glob_search" | "grep_search"
            )
        })
        .collect()
}

fn search_tool_specs(query: &str, max_results: usize, specs: &[ToolSpec]) -> Vec<String> {
    let lowered = query.to_lowercase();
    if let Some(selection) = lowered.strip_prefix("select:") {
        return selection
            .split(',')
            .map(str::trim)
            .filter(|part| !part.is_empty())
            .filter_map(|wanted| {
                let wanted = canonical_tool_token(wanted);
                specs
                    .iter()
                    .find(|spec| canonical_tool_token(spec.name) == wanted)
                    .map(|spec| spec.name.to_string())
            })
            .take(max_results)
            .collect();
    }

    let mut required = Vec::new();
    let mut optional = Vec::new();
    for term in lowered.split_whitespace() {
        if let Some(rest) = term.strip_prefix('+') {
            if !rest.is_empty() {
                required.push(rest);
            }
        } else {
            optional.push(term);
        }
    }
    let terms = if required.is_empty() {
        optional.clone()
    } else {
        required.iter().chain(optional.iter()).copied().collect()
    };

    let mut scored = specs
        .iter()
        .filter_map(|spec| {
            let name = spec.name.to_lowercase();
            let canonical_name = canonical_tool_token(spec.name);
            let normalized_description = normalize_tool_search_query(spec.description);
            let haystack = format!(
                "{name} {} {canonical_name}",
                spec.description.to_lowercase()
            );
            let normalized_haystack = format!("{canonical_name} {normalized_description}");
            if required.iter().any(|term| !haystack.contains(term)) {
                return None;
            }

            let mut score = 0_i32;
            for term in &terms {
                let canonical_term = canonical_tool_token(term);
                if haystack.contains(term) {
                    score += 2;
                }
                if name == *term {
                    score += 8;
                }
                if name.contains(term) {
                    score += 4;
                }
                if canonical_name == canonical_term {
                    score += 12;
                }
                if normalized_haystack.contains(&canonical_term) {
                    score += 3;
                }
            }

            if score == 0 && !lowered.is_empty() {
                return None;
            }
            Some((score, spec.name.to_string()))
        })
        .collect::<Vec<_>>();

    scored.sort_by(|left, right| right.0.cmp(&left.0).then_with(|| left.1.cmp(&right.1)));
    scored
        .into_iter()
        .map(|(_, name)| name)
        .take(max_results)
        .collect()
}

fn normalize_tool_search_query(query: &str) -> String {
    query
        .trim()
        .split(|ch: char| ch.is_whitespace() || ch == ',')
        .filter(|term| !term.is_empty())
        .map(canonical_tool_token)
        .collect::<Vec<_>>()
        .join(" ")
}

fn canonical_tool_token(value: &str) -> String {
    let mut canonical = value
        .chars()
        .filter(|ch| ch.is_ascii_alphanumeric())
        .flat_map(char::to_lowercase)
        .collect::<String>();
    if let Some(stripped) = canonical.strip_suffix("tool") {
        canonical = stripped.to_string();
    }
    canonical
}

fn agent_store_dir() -> Result<std::path::PathBuf, String> {
    if let Ok(path) = std::env::var("CLAWD_AGENT_STORE") {
        return Ok(std::path::PathBuf::from(path));
    }
    let cwd = std::env::current_dir().map_err(|error| error.to_string())?;
    Ok(cwd.join(".clawd-agents"))
}

fn make_agent_id() -> String {
    let nanos = std::time::SystemTime::now()
        .duration_since(std::time::UNIX_EPOCH)
        .unwrap_or_default()
        .as_nanos();
    format!("agent-{nanos}")
}

fn slugify_agent_name(description: &str) -> String {
    let mut out = description
        .chars()
        .map(|ch| {
            if ch.is_ascii_alphanumeric() {
                ch.to_ascii_lowercase()
            } else {
                '-'
            }
        })
        .collect::<String>();
    while out.contains("--") {
        out = out.replace("--", "-");
    }
    out.trim_matches('-').chars().take(32).collect()
}

fn normalize_subagent_type(subagent_type: Option<&str>) -> String {
    let trimmed = subagent_type.map(str::trim).unwrap_or_default();
    if trimmed.is_empty() {
        return String::from("general-purpose");
    }

    match canonical_tool_token(trimmed).as_str() {
        "general" | "generalpurpose" | "generalpurposeagent" => String::from("general-purpose"),
        "explore" | "explorer" | "exploreagent" => String::from("Explore"),
        "plan" | "planagent" => String::from("Plan"),
        "verification" | "verificationagent" | "verify" | "verifier" => {
            String::from("Verification")
        }
        "claudecodeguide" | "claudecodeguideagent" | "guide" => String::from("claude-code-guide"),
        "statusline" | "statuslinesetup" => String::from("statusline-setup"),
        _ => trimmed.to_string(),
    }
}

fn iso8601_now() -> String {
    std::time::SystemTime::now()
        .duration_since(std::time::UNIX_EPOCH)
        .unwrap_or_default()
        .as_secs()
        .to_string()
}

fn execute_notebook_edit(input: NotebookEditInput) -> Result<NotebookEditOutput, String> {
    let path = std::path::PathBuf::from(&input.notebook_path);
    if path.extension().and_then(|ext| ext.to_str()) != Some("ipynb") {
        return Err(String::from(
            "File must be a Jupyter notebook (.ipynb file).",
        ));
    }

    let original_file = std::fs::read_to_string(&path).map_err(|error| error.to_string())?;
    let mut notebook: serde_json::Value =
        serde_json::from_str(&original_file).map_err(|error| error.to_string())?;
    let language = notebook
        .get("metadata")
        .and_then(|metadata| metadata.get("kernelspec"))
        .and_then(|kernelspec| kernelspec.get("language"))
        .and_then(serde_json::Value::as_str)
        .unwrap_or("python")
        .to_string();
    let cells = notebook
        .get_mut("cells")
        .and_then(serde_json::Value::as_array_mut)
        .ok_or_else(|| String::from("Notebook cells array not found"))?;

    let edit_mode = input.edit_mode.unwrap_or(NotebookEditMode::Replace);
    let target_index = match input.cell_id.as_deref() {
        Some(cell_id) => Some(resolve_cell_index(cells, Some(cell_id), edit_mode)?),
        None if matches!(
            edit_mode,
            NotebookEditMode::Replace | NotebookEditMode::Delete
        ) =>
        {
            Some(resolve_cell_index(cells, None, edit_mode)?)
        }
        None => None,
    };
    let resolved_cell_type = match edit_mode {
        NotebookEditMode::Delete => None,
        NotebookEditMode::Insert => Some(input.cell_type.unwrap_or(NotebookCellType::Code)),
        NotebookEditMode::Replace => Some(input.cell_type.unwrap_or_else(|| {
            target_index
                .and_then(|index| cells.get(index))
                .and_then(cell_kind)
                .unwrap_or(NotebookCellType::Code)
        })),
    };
    let new_source = require_notebook_source(input.new_source, edit_mode)?;

    let cell_id = match edit_mode {
        NotebookEditMode::Insert => {
            let resolved_cell_type = resolved_cell_type.expect("insert cell type");
            let new_id = make_cell_id(cells.len());
            let new_cell = build_notebook_cell(&new_id, resolved_cell_type, &new_source);
            let insert_at = target_index.map_or(cells.len(), |index| index + 1);
            cells.insert(insert_at, new_cell);
            cells
                .get(insert_at)
                .and_then(|cell| cell.get("id"))
                .and_then(serde_json::Value::as_str)
                .map(ToString::to_string)
        }
        NotebookEditMode::Delete => {
            let removed = cells.remove(target_index.expect("delete target index"));
            removed
                .get("id")
                .and_then(serde_json::Value::as_str)
                .map(ToString::to_string)
        }
        NotebookEditMode::Replace => {
            let resolved_cell_type = resolved_cell_type.expect("replace cell type");
            let cell = cells
                .get_mut(target_index.expect("replace target index"))
                .ok_or_else(|| String::from("Cell index out of range"))?;
            cell["source"] = serde_json::Value::Array(source_lines(&new_source));
            cell["cell_type"] = serde_json::Value::String(match resolved_cell_type {
                NotebookCellType::Code => String::from("code"),
                NotebookCellType::Markdown => String::from("markdown"),
            });
            match resolved_cell_type {
                NotebookCellType::Code => {
                    if !cell.get("outputs").is_some_and(serde_json::Value::is_array) {
                        cell["outputs"] = json!([]);
                    }
                    if !cell.get("execution_count").is_some() {
                        cell["execution_count"] = serde_json::Value::Null;
                    }
                }
                NotebookCellType::Markdown => {
                    if let Some(object) = cell.as_object_mut() {
                        object.remove("outputs");
                        object.remove("execution_count");
                    }
                }
            }
            cell.get("id")
                .and_then(serde_json::Value::as_str)
                .map(ToString::to_string)
        }
    };

    let updated_file =
        serde_json::to_string_pretty(&notebook).map_err(|error| error.to_string())?;
    std::fs::write(&path, &updated_file).map_err(|error| error.to_string())?;

    Ok(NotebookEditOutput {
        new_source,
        cell_id,
        cell_type: resolved_cell_type,
        language,
        edit_mode: format_notebook_edit_mode(edit_mode),
        error: None,
        notebook_path: path.display().to_string(),
        original_file,
        updated_file,
    })
}

fn require_notebook_source(
    source: Option<String>,
    edit_mode: NotebookEditMode,
) -> Result<String, String> {
    match edit_mode {
        NotebookEditMode::Delete => Ok(source.unwrap_or_default()),
        NotebookEditMode::Insert | NotebookEditMode::Replace => source
            .ok_or_else(|| String::from("new_source is required for insert and replace edits")),
    }
}

fn build_notebook_cell(cell_id: &str, cell_type: NotebookCellType, source: &str) -> Value {
    let mut cell = json!({
        "cell_type": match cell_type {
            NotebookCellType::Code => "code",
            NotebookCellType::Markdown => "markdown",
        },
        "id": cell_id,
        "metadata": {},
        "source": source_lines(source),
    });
    if let Some(object) = cell.as_object_mut() {
        match cell_type {
            NotebookCellType::Code => {
                object.insert(String::from("outputs"), json!([]));
                object.insert(String::from("execution_count"), Value::Null);
            }
            NotebookCellType::Markdown => {}
        }
    }
    cell
}

fn cell_kind(cell: &serde_json::Value) -> Option<NotebookCellType> {
    cell.get("cell_type")
        .and_then(serde_json::Value::as_str)
        .map(|kind| {
            if kind == "markdown" {
                NotebookCellType::Markdown
            } else {
                NotebookCellType::Code
            }
        })
}

fn execute_sleep(input: SleepInput) -> SleepOutput {
    std::thread::sleep(Duration::from_millis(input.duration_ms));
    SleepOutput {
        duration_ms: input.duration_ms,
        message: format!("Slept for {}ms", input.duration_ms),
    }
}

fn execute_powershell(input: PowerShellInput) -> std::io::Result<runtime::BashCommandOutput> {
    let _ = &input.description;
    let shell = detect_powershell_shell();
    execute_shell_command(
        shell,
        &input.command,
        input.timeout,
        input.run_in_background,
    )
}

fn detect_powershell_shell() -> &'static str {
    if command_exists("pwsh") {
        "pwsh"
    } else {
        "powershell"
    }
}

fn command_exists(command: &str) -> bool {
    std::process::Command::new("sh")
        .arg("-lc")
        .arg(format!("command -v {command} >/dev/null 2>&1"))
        .status()
        .map(|status| status.success())
        .unwrap_or(false)
}

fn execute_shell_command(
    shell: &str,
    command: &str,
    timeout: Option<u64>,
    run_in_background: Option<bool>,
) -> std::io::Result<runtime::BashCommandOutput> {
    if run_in_background.unwrap_or(false) {
        let child = std::process::Command::new(shell)
            .arg("-NoProfile")
            .arg("-NonInteractive")
            .arg("-Command")
            .arg(command)
            .stdin(std::process::Stdio::null())
            .stdout(std::process::Stdio::null())
            .stderr(std::process::Stdio::null())
            .spawn()?;
        return Ok(runtime::BashCommandOutput {
            stdout: String::new(),
            stderr: String::new(),
            raw_output_path: None,
            interrupted: false,
            is_image: None,
            background_task_id: Some(child.id().to_string()),
            backgrounded_by_user: Some(false),
            assistant_auto_backgrounded: Some(false),
            dangerously_disable_sandbox: None,
            return_code_interpretation: None,
            no_output_expected: Some(true),
            structured_content: None,
            persisted_output_path: None,
            persisted_output_size: None,
        });
    }

    let mut process = std::process::Command::new(shell);
    process
        .arg("-NoProfile")
        .arg("-NonInteractive")
        .arg("-Command")
        .arg(command);
    process
        .stdout(std::process::Stdio::piped())
        .stderr(std::process::Stdio::piped());

    if let Some(timeout_ms) = timeout {
        let mut child = process.spawn()?;
        let started = Instant::now();
        loop {
            if let Some(status) = child.try_wait()? {
                let output = child.wait_with_output()?;
                return Ok(runtime::BashCommandOutput {
                    stdout: String::from_utf8_lossy(&output.stdout).into_owned(),
                    stderr: String::from_utf8_lossy(&output.stderr).into_owned(),
                    raw_output_path: None,
                    interrupted: false,
                    is_image: None,
                    background_task_id: None,
                    backgrounded_by_user: None,
                    assistant_auto_backgrounded: None,
                    dangerously_disable_sandbox: None,
                    return_code_interpretation: status
                        .code()
                        .filter(|code| *code != 0)
                        .map(|code| format!("exit_code:{code}")),
                    no_output_expected: Some(output.stdout.is_empty() && output.stderr.is_empty()),
                    structured_content: None,
                    persisted_output_path: None,
                    persisted_output_size: None,
                });
            }
            if started.elapsed() >= Duration::from_millis(timeout_ms) {
                let _ = child.kill();
                let output = child.wait_with_output()?;
                let stderr = String::from_utf8_lossy(&output.stderr).into_owned();
                let stderr = if stderr.trim().is_empty() {
                    format!("Command exceeded timeout of {timeout_ms} ms")
                } else {
                    format!(
                        "{}
Command exceeded timeout of {timeout_ms} ms",
                        stderr.trim_end()
                    )
                };
                return Ok(runtime::BashCommandOutput {
                    stdout: String::from_utf8_lossy(&output.stdout).into_owned(),
                    stderr,
                    raw_output_path: None,
                    interrupted: true,
                    is_image: None,
                    background_task_id: None,
                    backgrounded_by_user: None,
                    assistant_auto_backgrounded: None,
                    dangerously_disable_sandbox: None,
                    return_code_interpretation: Some(String::from("timeout")),
                    no_output_expected: Some(false),
                    structured_content: None,
                    persisted_output_path: None,
                    persisted_output_size: None,
                });
            }
            std::thread::sleep(Duration::from_millis(10));
        }
    }

    let output = process.output()?;
    Ok(runtime::BashCommandOutput {
        stdout: String::from_utf8_lossy(&output.stdout).into_owned(),
        stderr: String::from_utf8_lossy(&output.stderr).into_owned(),
        raw_output_path: None,
        interrupted: false,
        is_image: None,
        background_task_id: None,
        backgrounded_by_user: None,
        assistant_auto_backgrounded: None,
        dangerously_disable_sandbox: None,
        return_code_interpretation: output
            .status
            .code()
            .filter(|code| *code != 0)
            .map(|code| format!("exit_code:{code}")),
        no_output_expected: Some(output.stdout.is_empty() && output.stderr.is_empty()),
        structured_content: None,
        persisted_output_path: None,
        persisted_output_size: None,
    })
}

fn resolve_cell_index(
    cells: &[serde_json::Value],
    cell_id: Option<&str>,
    edit_mode: NotebookEditMode,
) -> Result<usize, String> {
    if cells.is_empty()
        && matches!(
            edit_mode,
            NotebookEditMode::Replace | NotebookEditMode::Delete
        )
    {
        return Err(String::from("Notebook has no cells to edit"));
    }
    if let Some(cell_id) = cell_id {
        cells
            .iter()
            .position(|cell| cell.get("id").and_then(serde_json::Value::as_str) == Some(cell_id))
            .ok_or_else(|| format!("Cell id not found: {cell_id}"))
    } else {
        Ok(cells.len().saturating_sub(1))
    }
}

fn source_lines(source: &str) -> Vec<serde_json::Value> {
    if source.is_empty() {
        return vec![serde_json::Value::String(String::new())];
    }
    source
        .split_inclusive('\n')
        .map(|line| serde_json::Value::String(line.to_string()))
        .collect()
}

fn format_notebook_edit_mode(mode: NotebookEditMode) -> String {
    match mode {
        NotebookEditMode::Replace => String::from("replace"),
        NotebookEditMode::Insert => String::from("insert"),
        NotebookEditMode::Delete => String::from("delete"),
    }
}

fn make_cell_id(index: usize) -> String {
    format!("cell-{}", index + 1)
}

fn parse_skill_description(contents: &str) -> Option<String> {
    for line in contents.lines() {
        if let Some(value) = line.strip_prefix("description:") {
            let trimmed = value.trim();
            if !trimmed.is_empty() {
                return Some(trimmed.to_string());
            }
        }
    }
    None
}

#[cfg(test)]
mod tests {
    use std::io::{Read, Write};
    use std::net::{SocketAddr, TcpListener};
    use std::sync::Arc;
    use std::thread;
    use std::time::Duration;

    use super::{execute_tool, mvp_tool_specs};
    use serde_json::json;

    #[test]
    fn exposes_mvp_tools() {
        let names = mvp_tool_specs()
            .into_iter()
            .map(|spec| spec.name)
            .collect::<Vec<_>>();
        assert!(names.contains(&"bash"));
        assert!(names.contains(&"read_file"));
        assert!(names.contains(&"WebFetch"));
        assert!(names.contains(&"WebSearch"));
        assert!(names.contains(&"TodoWrite"));
        assert!(names.contains(&"Skill"));
        assert!(names.contains(&"Agent"));
        assert!(names.contains(&"ToolSearch"));
        assert!(names.contains(&"NotebookEdit"));
        assert!(names.contains(&"Sleep"));
        assert!(names.contains(&"PowerShell"));
    }

    #[test]
    fn rejects_unknown_tool_names() {
        let error = execute_tool("nope", &json!({})).expect_err("tool should be rejected");
        assert!(error.contains("unsupported tool"));
    }

    #[test]
    fn web_fetch_returns_prompt_aware_summary() {
        let server = TestServer::spawn(Arc::new(|request_line: &str| {
            assert!(request_line.starts_with("GET /page "));
            HttpResponse::html(
                200,
                "OK",
                "<html><head><title>Ignored</title></head><body><h1>Test Page</h1><p>Hello <b>world</b> from local server.</p></body></html>",
            )
        }));

        let result = execute_tool(
            "WebFetch",
            &json!({
                "url": format!("http://{}/page", server.addr()),
                "prompt": "Summarize this page"
            }),
        )
        .expect("WebFetch should succeed");

        let output: serde_json::Value = serde_json::from_str(&result).expect("valid json");
        assert_eq!(output["code"], 200);
        let summary = output["result"].as_str().expect("result string");
        assert!(summary.contains("Fetched"));
        assert!(summary.contains("Test Page"));
        assert!(summary.contains("Hello world from local server"));
    }

    #[test]
    fn web_search_extracts_and_filters_results() {
        let server = TestServer::spawn(Arc::new(|request_line: &str| {
            assert!(request_line.contains("GET /search?q=rust+web+search "));
            HttpResponse::html(
                200,
                "OK",
                r#"
                <html><body>
                  <a class="result__a" href="https://docs.rs/reqwest">Reqwest docs</a>
                  <a class="result__a" href="https://example.com/blocked">Blocked result</a>
                </body></html>
                "#,
            )
        }));

        std::env::set_var(
            "CLAWD_WEB_SEARCH_BASE_URL",
            format!("http://{}/search", server.addr()),
        );
        let result = execute_tool(
            "WebSearch",
            &json!({
                "query": "rust web search",
                "allowed_domains": ["docs.rs"],
                "blocked_domains": ["example.com"]
            }),
        )
        .expect("WebSearch should succeed");
        std::env::remove_var("CLAWD_WEB_SEARCH_BASE_URL");

        let output: serde_json::Value = serde_json::from_str(&result).expect("valid json");
        assert_eq!(output["query"], "rust web search");
        let results = output["results"].as_array().expect("results array");
        let search_result = results
            .iter()
            .find(|item| item.get("content").is_some())
            .expect("search result block present");
        let content = search_result["content"].as_array().expect("content array");
        assert_eq!(content.len(), 1);
        assert_eq!(content[0]["title"], "Reqwest docs");
        assert_eq!(content[0]["url"], "https://docs.rs/reqwest");
    }

    #[test]
    fn todo_write_persists_and_returns_previous_state() {
        let path = std::env::temp_dir().join(format!(
            "clawd-tools-todos-{}.json",
            std::time::SystemTime::now()
                .duration_since(std::time::UNIX_EPOCH)
                .expect("time")
                .as_nanos()
        ));
        std::env::set_var("CLAWD_TODO_STORE", &path);

        let first = execute_tool(
            "TodoWrite",
            &json!({
                "todos": [
                    {"content": "Add tool", "activeForm": "Adding tool", "status": "in_progress"},
                    {"content": "Run tests", "activeForm": "Running tests", "status": "pending"}
                ]
            }),
        )
        .expect("TodoWrite should succeed");
        let first_output: serde_json::Value = serde_json::from_str(&first).expect("valid json");
        assert_eq!(first_output["oldTodos"].as_array().expect("array").len(), 0);

        let second = execute_tool(
            "TodoWrite",
            &json!({
                "todos": [
                    {"content": "Add tool", "activeForm": "Adding tool", "status": "completed"},
                    {"content": "Run tests", "activeForm": "Running tests", "status": "completed"},
                    {"content": "Verify", "activeForm": "Verifying", "status": "completed"}
                ]
            }),
        )
        .expect("TodoWrite should succeed");
        std::env::remove_var("CLAWD_TODO_STORE");
        let _ = std::fs::remove_file(path);

        let second_output: serde_json::Value = serde_json::from_str(&second).expect("valid json");
        assert_eq!(
            second_output["oldTodos"].as_array().expect("array").len(),
            2
        );
        assert_eq!(
            second_output["newTodos"].as_array().expect("array").len(),
            3
        );
        assert!(second_output["verificationNudgeNeeded"].is_null());
    }

    #[test]
    fn skill_loads_local_skill_prompt() {
        let result = execute_tool(
            "Skill",
            &json!({
                "skill": "help",
                "args": "overview"
            }),
        )
        .expect("Skill should succeed");

        let output: serde_json::Value = serde_json::from_str(&result).expect("valid json");
        assert_eq!(output["skill"], "help");
        assert!(output["path"]
            .as_str()
            .expect("path")
            .ends_with("/help/SKILL.md"));
        assert!(output["prompt"]
            .as_str()
            .expect("prompt")
            .contains("Guide on using oh-my-codex plugin"));
    }

    #[test]
    fn tool_search_supports_keyword_and_select_queries() {
        let keyword = execute_tool(
            "ToolSearch",
            &json!({"query": "web current", "max_results": 3}),
        )
        .expect("ToolSearch should succeed");
        let keyword_output: serde_json::Value = serde_json::from_str(&keyword).expect("valid json");
        let matches = keyword_output["matches"].as_array().expect("matches");
        assert!(matches.iter().any(|value| value == "WebSearch"));

        let selected = execute_tool("ToolSearch", &json!({"query": "select:Agent,Skill"}))
            .expect("ToolSearch should succeed");
        let selected_output: serde_json::Value =
            serde_json::from_str(&selected).expect("valid json");
        assert_eq!(selected_output["matches"][0], "Agent");
        assert_eq!(selected_output["matches"][1], "Skill");

        let aliased = execute_tool("ToolSearch", &json!({"query": "AgentTool"}))
            .expect("ToolSearch should support tool aliases");
        let aliased_output: serde_json::Value = serde_json::from_str(&aliased).expect("valid json");
        assert_eq!(aliased_output["matches"][0], "Agent");
        assert_eq!(aliased_output["normalized_query"], "agent");

        let selected_with_alias =
            execute_tool("ToolSearch", &json!({"query": "select:AgentTool,Skill"}))
                .expect("ToolSearch alias select should succeed");
        let selected_with_alias_output: serde_json::Value =
            serde_json::from_str(&selected_with_alias).expect("valid json");
        assert_eq!(selected_with_alias_output["matches"][0], "Agent");
        assert_eq!(selected_with_alias_output["matches"][1], "Skill");
    }

    #[test]
    fn agent_persists_handoff_metadata() {
        let dir = std::env::temp_dir().join(format!(
            "clawd-agent-store-{}",
            std::time::SystemTime::now()
                .duration_since(std::time::UNIX_EPOCH)
                .expect("time")
                .as_nanos()
        ));
        std::env::set_var("CLAWD_AGENT_STORE", &dir);

        let result = execute_tool(
            "Agent",
            &json!({
                "description": "Audit the branch",
                "prompt": "Check tests and outstanding work.",
                "subagent_type": "Explore",
                "name": "ship-audit"
            }),
        )
        .expect("Agent should succeed");
        std::env::remove_var("CLAWD_AGENT_STORE");

        let output: serde_json::Value = serde_json::from_str(&result).expect("valid json");
        assert_eq!(output["name"], "ship-audit");
        assert_eq!(output["subagentType"], "Explore");
        assert_eq!(output["status"], "queued");
        assert!(output["createdAt"].as_str().is_some());
        let manifest_file = output["manifestFile"].as_str().expect("manifest file");
        let output_file = output["outputFile"].as_str().expect("output file");
        let contents = std::fs::read_to_string(output_file).expect("agent file exists");
        let manifest_contents =
            std::fs::read_to_string(manifest_file).expect("manifest file exists");
        assert!(contents.contains("Audit the branch"));
        assert!(contents.contains("Check tests and outstanding work."));
        assert!(manifest_contents.contains("\"subagentType\": \"Explore\""));

        let normalized = execute_tool(
            "Agent",
            &json!({
                "description": "Verify the branch",
                "prompt": "Check tests.",
                "subagent_type": "explorer"
            }),
        )
        .expect("Agent should normalize built-in aliases");
        let normalized_output: serde_json::Value =
            serde_json::from_str(&normalized).expect("valid json");
        assert_eq!(normalized_output["subagentType"], "Explore");
        let _ = std::fs::remove_dir_all(dir);
    }

    #[test]
    fn notebook_edit_replaces_inserts_and_deletes_cells() {
        let path = std::env::temp_dir().join(format!(
            "clawd-notebook-{}.ipynb",
            std::time::SystemTime::now()
                .duration_since(std::time::UNIX_EPOCH)
                .expect("time")
                .as_nanos()
        ));
        std::fs::write(
            &path,
            r#"{
  "cells": [
    {"cell_type": "code", "id": "cell-a", "metadata": {}, "source": ["print(1)\n"], "outputs": [], "execution_count": null}
  ],
  "metadata": {"kernelspec": {"language": "python"}},
  "nbformat": 4,
  "nbformat_minor": 5
}"#,
        )
        .expect("write notebook");

        let replaced = execute_tool(
            "NotebookEdit",
            &json!({
                "notebook_path": path.display().to_string(),
                "cell_id": "cell-a",
                "new_source": "print(2)\n",
                "edit_mode": "replace"
            }),
        )
        .expect("NotebookEdit replace should succeed");
        let replaced_output: serde_json::Value = serde_json::from_str(&replaced).expect("json");
        assert_eq!(replaced_output["cell_id"], "cell-a");
        assert_eq!(replaced_output["cell_type"], "code");

        let inserted = execute_tool(
            "NotebookEdit",
            &json!({
                "notebook_path": path.display().to_string(),
                "cell_id": "cell-a",
                "new_source": "# heading\n",
                "cell_type": "markdown",
                "edit_mode": "insert"
            }),
        )
        .expect("NotebookEdit insert should succeed");
        let inserted_output: serde_json::Value = serde_json::from_str(&inserted).expect("json");
        assert_eq!(inserted_output["cell_type"], "markdown");
        let appended = execute_tool(
            "NotebookEdit",
            &json!({
                "notebook_path": path.display().to_string(),
                "new_source": "print(3)\n",
                "edit_mode": "insert"
            }),
        )
        .expect("NotebookEdit append should succeed");
        let appended_output: serde_json::Value = serde_json::from_str(&appended).expect("json");
        assert_eq!(appended_output["cell_type"], "code");

        let deleted = execute_tool(
            "NotebookEdit",
            &json!({
                "notebook_path": path.display().to_string(),
                "cell_id": "cell-a",
                "edit_mode": "delete"
            }),
        )
        .expect("NotebookEdit delete should succeed without new_source");
        let deleted_output: serde_json::Value = serde_json::from_str(&deleted).expect("json");
        assert!(deleted_output["cell_type"].is_null());
        assert_eq!(deleted_output["new_source"], "");

        let final_notebook: serde_json::Value =
            serde_json::from_str(&std::fs::read_to_string(&path).expect("read notebook"))
                .expect("valid notebook json");
        let cells = final_notebook["cells"].as_array().expect("cells array");
        assert_eq!(cells.len(), 2);
        assert_eq!(cells[0]["cell_type"], "markdown");
        assert!(cells[0].get("outputs").is_none());
        assert_eq!(cells[1]["cell_type"], "code");
        assert_eq!(cells[1]["source"][0], "print(3)\n");
        let _ = std::fs::remove_file(path);
    }

    #[test]
    fn sleep_waits_and_reports_duration() {
        let started = std::time::Instant::now();
        let result =
            execute_tool("Sleep", &json!({"duration_ms": 20})).expect("Sleep should succeed");
        let elapsed = started.elapsed();
        let output: serde_json::Value = serde_json::from_str(&result).expect("json");
        assert_eq!(output["duration_ms"], 20);
        assert!(output["message"]
            .as_str()
            .expect("message")
            .contains("Slept for 20ms"));
        assert!(elapsed >= Duration::from_millis(15));
    }

    #[test]
    fn powershell_runs_via_stub_shell() {
        let dir = std::env::temp_dir().join(format!(
            "clawd-pwsh-bin-{}",
            std::time::SystemTime::now()
                .duration_since(std::time::UNIX_EPOCH)
                .expect("time")
                .as_nanos()
        ));
        std::fs::create_dir_all(&dir).expect("create dir");
        let script = dir.join("pwsh");
        std::fs::write(
            &script,
            r#"#!/bin/sh
while [ "$1" != "-Command" ] && [ $# -gt 0 ]; do shift; done
shift
printf 'pwsh:%s' "$1"
"#,
        )
        .expect("write script");
        std::process::Command::new("chmod")
            .arg("+x")
            .arg(&script)
            .status()
            .expect("chmod");
        let original_path = std::env::var("PATH").unwrap_or_default();
        std::env::set_var("PATH", format!("{}:{}", dir.display(), original_path));

        let result = execute_tool(
            "PowerShell",
            &json!({"command": "Write-Output hello", "timeout": 1000}),
        )
        .expect("PowerShell should succeed");

        std::env::set_var("PATH", original_path);
        let _ = std::fs::remove_dir_all(dir);

        let output: serde_json::Value = serde_json::from_str(&result).expect("json");
        assert_eq!(output["stdout"], "pwsh:Write-Output hello");
        assert!(output["stderr"].as_str().expect("stderr").is_empty());
    }

    struct TestServer {
        addr: SocketAddr,
        shutdown: Option<std::sync::mpsc::Sender<()>>,
        handle: Option<thread::JoinHandle<()>>,
    }

    impl TestServer {
        fn spawn(handler: Arc<dyn Fn(&str) -> HttpResponse + Send + Sync + 'static>) -> Self {
            let listener = TcpListener::bind("127.0.0.1:0").expect("bind test server");
            listener
                .set_nonblocking(true)
                .expect("set nonblocking listener");
            let addr = listener.local_addr().expect("local addr");
            let (tx, rx) = std::sync::mpsc::channel::<()>();

            let handle = thread::spawn(move || loop {
                if rx.try_recv().is_ok() {
                    break;
                }

                match listener.accept() {
                    Ok((mut stream, _)) => {
                        let mut buffer = [0_u8; 4096];
                        let size = stream.read(&mut buffer).expect("read request");
                        let request = String::from_utf8_lossy(&buffer[..size]).into_owned();
                        let request_line = request.lines().next().unwrap_or_default().to_string();
                        let response = handler(&request_line);
                        stream
                            .write_all(response.to_bytes().as_slice())
                            .expect("write response");
                    }
                    Err(error) if error.kind() == std::io::ErrorKind::WouldBlock => {
                        thread::sleep(Duration::from_millis(10));
                    }
                    Err(error) => panic!("server accept failed: {error}"),
                }
            });

            Self {
                addr,
                shutdown: Some(tx),
                handle: Some(handle),
            }
        }

        fn addr(&self) -> SocketAddr {
            self.addr
        }
    }

    impl Drop for TestServer {
        fn drop(&mut self) {
            if let Some(tx) = self.shutdown.take() {
                let _ = tx.send(());
            }
            if let Some(handle) = self.handle.take() {
                handle.join().expect("join test server");
            }
        }
    }

    struct HttpResponse {
        status: u16,
        reason: &'static str,
        content_type: &'static str,
        body: String,
    }

    impl HttpResponse {
        fn html(status: u16, reason: &'static str, body: &str) -> Self {
            Self {
                status,
                reason,
                content_type: "text/html; charset=utf-8",
                body: body.to_string(),
            }
        }

        fn to_bytes(&self) -> Vec<u8> {
            format!(
                "HTTP/1.1 {} {}\r\nContent-Type: {}\r\nContent-Length: {}\r\nConnection: close\r\n\r\n{}",
                self.status,
                self.reason,
                self.content_type,
                self.body.len(),
                self.body
            )
            .into_bytes()
        }
    }
}