// tools/mod.rs — Agent-specific tool dispatch
//
// Shared tools (memory, files, bash, journal) live in thought/.
// This module handles agent-specific tools (control, vision,
// working_stack) and delegates everything else to thought::dispatch.

// Core tools
mod bash;
pub mod channels;
mod edit;
mod glob;
mod grep;
pub mod memory;
mod read;
mod web;
mod write;

// Agent-specific tools
mod control;
mod vision;
pub mod working_stack;

use serde::{Serialize, Deserialize};
use std::future::Future;
use std::pin::Pin;
use std::time::Instant;

fn default_timeout() -> u64 { 120 }

/// Async tool handler function.
/// Agent is None when called from contexts without an agent (MCP server, subconscious).
pub type ToolHandler = fn(
    Option<std::sync::Arc<tokio::sync::Mutex<super::Agent>>>,
    serde_json::Value,
) -> Pin<Box<dyn Future<Output = anyhow::Result<String>> + Send>>;

/// A tool with its definition and handler — single source of truth.
pub struct Tool {
    pub def: ToolDef,
    pub handler: ToolHandler,
}

/// Function call within a tool call — name + JSON arguments.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct FunctionCall {
    pub name: String,
    pub arguments: String,
}

/// Function definition for tool schema.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct FunctionDef {
    pub name: String,
    pub description: String,
    pub parameters: serde_json::Value,
}

/// Partial function call within a streaming delta.
#[derive(Debug, Deserialize)]
pub struct FunctionCallDelta {
    pub name: Option<String>,
    pub arguments: Option<String>,
}

/// Tool definition sent to the model.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ToolDef {
    #[serde(rename = "type")]
    pub tool_type: String,
    pub function: FunctionDef,
}

impl ToolDef {
    pub fn new(name: &str, description: &str, parameters: serde_json::Value) -> Self {
        Self {
            tool_type: "function".to_string(),
            function: FunctionDef {
                name: name.to_string(),
                description: description.to_string(),
                parameters,
            },
        }
    }
}

/// A tool call requested by the model.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ToolCall {
    pub id: String,
    #[serde(rename = "type")]
    pub call_type: String,
    pub function: FunctionCall,
}

/// A partial tool call within a streaming delta. The first chunk for a
/// given tool call carries the id and function name; subsequent chunks
/// carry argument fragments.
#[derive(Debug, Deserialize)]
pub struct ToolCallDelta {
    pub index: usize,
    pub id: Option<String>,
    #[serde(rename = "type")]
    pub call_type: Option<String>,
    pub function: Option<FunctionCallDelta>,
}

/// Result of dispatching a tool call.
pub struct ToolOutput {
    pub text: String,
    pub is_yield: bool,
    /// Base64 data URIs for images to attach to the next message.
    pub images: Vec<String>,
    /// Model name to switch to (deferred to session level).
    pub model_switch: Option<String>,
    /// Agent requested DMN pause (deferred to session level).
    pub dmn_pause: bool,
}

impl ToolOutput {
    pub fn error(e: impl std::fmt::Display) -> Self {
        Self {
            text: format!("Error: {}", e),
            is_yield: false,
            images: Vec::new(),
            model_switch: None,
            dmn_pause: false,
        }
    }

    pub fn text(s: String) -> Self {
        Self {
            text: s,
            is_yield: false,
            images: Vec::new(),
            model_switch: None,
            dmn_pause: false,
        }
    }
}

/// A tool call in flight — metadata for TUI + JoinHandle for
/// result collection and cancellation.
pub struct ActiveToolCall {
    pub id: String,
    pub name: String,
    pub detail: String,
    pub started: Instant,
    pub background: bool,
    pub handle: tokio::task::JoinHandle<(ToolCall, ToolOutput)>,
}

/// Truncate output if it exceeds max length, appending a truncation notice.
pub fn truncate_output(mut s: String, max: usize) -> String {
    if s.len() > max {
        s.truncate(max);
        s.push_str("\n... (output truncated)");
    }
    s
}

/// Dispatch a tool call by name through the registry.
pub async fn dispatch(
    name: &str,
    args: &serde_json::Value,
) -> ToolOutput {
    dispatch_with_agent(name, args, None).await
}

/// Dispatch a tool call with optional agent context.
pub async fn dispatch_with_agent(
    name: &str,
    args: &serde_json::Value,
    agent: Option<std::sync::Arc<tokio::sync::Mutex<super::Agent>>>,
) -> ToolOutput {
    for tool in tools() {
        if tool.def.function.name == name {
            return match (tool.handler)(agent, args.clone()).await {
                Ok(s) => ToolOutput::text(s),
                Err(e) => ToolOutput::error(e),
            };
        }
    }
    ToolOutput::error(format!("Unknown tool: {}", name))
}

/// Dispatch shared tools — used by subconscious agents.
pub async fn dispatch_shared(
    name: &str,
    args: &serde_json::Value,
    _provenance: Option<&str>,
) -> Option<ToolOutput> {
    for tool in tools() {
        if tool.def.function.name == name {
            return Some(match (tool.handler)(None, args.clone()).await {
                Ok(s) => ToolOutput::text(s),
                Err(e) => ToolOutput::error(e),
            });
        }
    }
    None
}

/// Return all registered tools with definitions + handlers.
pub fn tools() -> Vec<Tool> {
    vec![
        // File tools
        Tool { def: read::definition(),       handler: |_a, v| Box::pin(async move { read::read_file(&v) }) },
        Tool { def: write::definition(),      handler: |_a, v| Box::pin(async move { write::write_file(&v) }) },
        Tool { def: edit::definition(),       handler: |_a, v| Box::pin(async move { edit::edit_file(&v) }) },
        Tool { def: grep::definition(),       handler: |_a, v| Box::pin(async move { grep::grep(&v) }) },
        Tool { def: glob::definition(),       handler: |_a, v| Box::pin(async move { glob::glob_search(&v) }) },

        // Execution tools
        Tool { def: bash::definition(),       handler: |_a, v| Box::pin(async move { bash::run_bash(&v).await }) },
        Tool { def: web::fetch_definition(),  handler: |_a, v| Box::pin(async move { web::web_fetch(&v).await }) },
        Tool { def: web::search_definition(), handler: |_a, v| Box::pin(async move { web::web_search(&v).await }) },

        // Vision
        Tool { def: vision::definition(),     handler: |_a, v| Box::pin(async move { vision::view_image_text(&v) }) },

        // Memory tools
        Tool { def: memory::render_def(),     handler: |_a, v| Box::pin(async move { memory::render(&v) }) },
        Tool { def: memory::write_def(),      handler: |_a, v| Box::pin(async move { memory::write(&v) }) },
        Tool { def: memory::search_def(),     handler: |_a, v| Box::pin(async move { memory::search(&v) }) },
        Tool { def: memory::links_def(),      handler: |_a, v| Box::pin(async move { memory::links(&v) }) },
        Tool { def: memory::link_set_def(),   handler: |_a, v| Box::pin(async move { memory::link_set(&v) }) },
        Tool { def: memory::link_add_def(),   handler: |_a, v| Box::pin(async move { memory::link_add(&v) }) },
        Tool { def: memory::used_def(),       handler: |_a, v| Box::pin(async move { memory::used(&v) }) },
        Tool { def: memory::weight_set_def(), handler: |_a, v| Box::pin(async move { memory::weight_set(&v) }) },
        Tool { def: memory::rename_def(),     handler: |_a, v| Box::pin(async move { memory::rename(&v) }) },
        Tool { def: memory::supersede_def(),  handler: |_a, v| Box::pin(async move { memory::supersede(&v) }) },
        Tool { def: memory::query_def(),      handler: |_a, v| Box::pin(async move { memory::query(&v) }) },
        Tool { def: memory::output_def(),     handler: |_a, v| Box::pin(async move { memory::output(&v) }) },

        // Channel tools
        Tool { def: channels::definitions()[0].clone(), handler: |_a, v| Box::pin(async move { channels::channel_list().await }) },
        Tool { def: channels::definitions()[1].clone(), handler: |_a, v| Box::pin(async move { channels::channel_recv(&v).await }) },
        Tool { def: channels::definitions()[2].clone(), handler: |_a, v| Box::pin(async move { channels::channel_send(&v).await }) },
        Tool { def: channels::definitions()[3].clone(), handler: |_a, v| Box::pin(async move { channels::channel_notifications().await }) },

        // Control tools
        Tool { def: control::definitions()[0].clone(),
               handler: |_a, _v| Box::pin(async { Ok("Pausing autonomous behavior. Only user input will wake you.".into()) }) },
        Tool { def: control::definitions()[1].clone(),
               handler: |_a, v| Box::pin(async move {
                   let model = v.get("model").and_then(|v| v.as_str()).unwrap_or("");
                   Ok(format!("Switching to model: {}", model))
               }) },
        Tool { def: control::definitions()[2].clone(),
               handler: |_a, v| Box::pin(async move {
                   let msg = v.get("message").and_then(|v| v.as_str()).unwrap_or("(yielding to user)");
                   Ok(msg.to_string())
               }) },
    ]
}

/// Return all tool definitions (extracted from tools()).
pub fn definitions() -> Vec<ToolDef> {
    tools().into_iter().map(|t| t.def).collect()
}

/// Return memory + journal tool definitions only.
pub fn memory_and_journal_definitions() -> Vec<ToolDef> {
    let mut defs = memory::definitions();
    defs.extend(memory::journal_definitions());
    defs
}

/// Create a short summary of tool args for the tools pane header.
pub fn summarize_args(tool_name: &str, args: &serde_json::Value) -> String {
    match tool_name {
        "read_file" | "write_file" | "edit_file" => args["file_path"]
            .as_str()
            .unwrap_or("")
            .to_string(),
        "bash" => {
            let cmd = args["command"].as_str().unwrap_or("");
            if cmd.len() > 60 {
                let end = cmd.char_indices()
                    .map(|(i, _)| i)
                    .take_while(|&i| i <= 60)
                    .last()
                    .unwrap_or(0);
                format!("{}...", &cmd[..end])
            } else {
                cmd.to_string()
            }
        }
        "grep" => {
            let pattern = args["pattern"].as_str().unwrap_or("");
            let path = args["path"].as_str().unwrap_or(".");
            format!("{} in {}", pattern, path)
        }
        "glob" => args["pattern"]
            .as_str()
            .unwrap_or("")
            .to_string(),
        "view_image" => {
            if let Some(pane) = args["pane_id"].as_str() {
                format!("pane {}", pane)
            } else {
                args["file_path"].as_str().unwrap_or("").to_string()
            }
        }
        "journal" => {
            let entry = args["entry"].as_str().unwrap_or("");
            if entry.len() > 60 {
                format!("{}...", &entry[..60])
            } else {
                entry.to_string()
            }
        }
        "yield_to_user" => args["message"]
            .as_str()
            .unwrap_or("")
            .to_string(),
        "switch_model" => args["model"]
            .as_str()
            .unwrap_or("")
            .to_string(),
        "pause" => String::new(),
        _ => String::new(),
    }
}