//! Plan management tools — enter and mark ready.
//!
//! These tools implement a two-phase planning workflow: `PlanEnter` presents a
//! structured plan to the user for approval, and `PlanReady` signals that the
//! plan is finalised and execution may begin.

use crate::tools::{Tool, ToolCtx};
use anyhow::Result;
use serde_json::{json, Value};
use tracing::{info, instrument, warn};

/// Enter a planning phase — persist a structured plan and notify the user.
///
/// Flow: extract plan text → write to `{session_dir}/PLAN.md` → push a
/// `PlanUpdate` turn event → return plan length summary.
pub struct PlanEnter;

impl Tool for PlanEnter {
    fn name(&self) -> &'static str {
        "plan_enter"
    }

    fn description(&self) -> &'static str {
        "Enter a planning phase — present a structured plan for approval"
    }

    fn parameters(&self) -> Value {
        json!({
            "type": "object",
            "properties": {
                "plan": {
                    "type": "string",
                    "description": "The structured plan text"
                }
            },
            "required": ["plan"]
        })
    }

    #[instrument(skip(self, ctx, args))]
    fn run(&self, ctx: &ToolCtx, args: &Value) -> Result<String> {
        let plan_text = crate::tools::arg_str(args, "plan")?;
        info!(plan_len = plan_text.len(), "plan_enter called");

        let plan_path = ctx.session_dir.join("PLAN.md");
        let _ = std::fs::write(&plan_path, &plan_text);
        if let Some(events) = &ctx.turn_events {
            if let Ok(mut q) = events.lock() {
                q.push_back(crate::TurnEvent::PlanUpdate(plan_text.clone()));
            }
        }

        Ok(format!(
            "Plan entered (length: {} chars). Waiting for approval...",
            plan_text.len()
        ))
    }
}

/// Signal that the plan is ready and execution can begin.
///
/// Flow: extract plan content → persist to a timestamped file in
/// `{session_dir}/plans/` → overwrite `PLAN.md` → push `PlanUpdate` event.
pub struct PlanReady;

impl Tool for PlanReady {
    fn name(&self) -> &'static str {
        "plan_ready"
    }

    fn description(&self) -> &'static str {
        "Signal that the plan is ready and execution can begin"
    }

    fn parameters(&self) -> Value {
        json!({
            "type": "object",
            "properties": {
                "plan": {
                    "type": "string",
                    "description": "The final plan content"
                }
            },
            "required": ["plan"]
        })
    }

    #[instrument(skip(self, ctx, args))]
    fn run(&self, ctx: &ToolCtx, args: &Value) -> Result<String> {
        let plan_content = crate::tools::arg_str(args, "plan")?;
        info!(plan_len = plan_content.len(), "plan_ready called");

        // Persist the plan to session directory for reference
        let plan_dir = ctx.session_dir.join("plans");
        if std::fs::create_dir_all(&plan_dir).is_ok() {
            let filename = format!("plan-{}.md", chrono::Utc::now().format("%Y%m%d_%H%M%S"));
            let path = plan_dir.join(&filename);
            std::fs::write(&path, &plan_content)
                .map_err(|e| anyhow::anyhow!("failed to save plan: {e}"))?;

            info!(filename = %filename, "plan persisted to disk");

            // Also save the latest plan
            let plan_path = ctx.session_dir.join("PLAN.md");
            let _ = std::fs::write(&plan_path, &plan_content);
            if let Some(events) = &ctx.turn_events {
                if let Ok(mut q) = events.lock() {
                    q.push_back(crate::TurnEvent::PlanUpdate(plan_content.clone()));
                }
            }

            Ok(format!("Plan saved to {filename}. Starting execution."))
        } else {
            warn!("failed to create plans directory");
            Ok("Plan is ready. Starting execution.".to_string())
        }
    }
}