use std::collections::VecDeque;
use std::path::PathBuf;
use std::sync::{Arc, Mutex};
use tokio::sync::RwLock;

use super::misc::{DirCache, InputState, MiscState, ScrollState};
use super::runtime::{SessionRuntime, TurnEvent};
use super::types::{AgentMode, Origin, Toast, TranscriptCache};
use crate::app::mcp::manager::McpManager;
use crate::app::workflow::engine::WorkflowEngine;
use crate::model::editlog::EditLog;
use crate::model::settings::Settings;

#[derive(Debug, Clone, PartialEq)]
pub struct ChatMessageDisplay {
    pub role: crate::dto::chat::message::Role,
    pub content: String,
    pub timestamp: i64,
}

impl ChatMessageDisplay {
    pub fn new(role: crate::dto::chat::message::Role, content: String) -> Self {
        ChatMessageDisplay {
            role,
            content,
            timestamp: chrono::Utc::now().timestamp_millis(),
        }
    }
}

#[derive(Clone)]
pub struct AppStateRest {
    pub mode: AgentMode,
    pub settings: Settings,
    pub workspace_roots: Vec<PathBuf>,
    pub session_id: String,
    pub session_dir: PathBuf,
    pub memory_dir: PathBuf,
    pub download_dir: PathBuf,
    pub worktrees_dir: PathBuf,
    pub dir_cache: Arc<RwLock<DirCache>>,
    pub edit_log: EditLog,
    pub session_runtime: Option<SessionRuntime>,
    pub sessions: Vec<crate::model::session::Session>,
    pub transcript_cache: TranscriptCache,
    pub scroll: ScrollState,
    pub input: InputState,
    pub misc: MiscState,
    pub turn_events: Arc<Mutex<VecDeque<TurnEvent>>>,
    pub turn_in_flight: Arc<Mutex<bool>>,
    pub workflow_engine: WorkflowEngine,
    pub mcp_manager: McpManager,
    pub dirty: bool,
    pub quit: bool,
}

impl AppStateRest {
    pub fn new(workspace_roots: Vec<PathBuf>, session_dir: PathBuf, memory_dir: PathBuf) -> Self {
        let settings = Settings::load();
        let download_dir = memory_dir.parent().unwrap_or(&memory_dir).join("downloads");
        let worktrees_dir = memory_dir.parent().unwrap_or(&memory_dir).join("worktrees");
        let dir_cache = DirCache::new();
        let session_id = session_dir
            .file_name()
            .map(|n| n.to_string_lossy().to_string())
            .unwrap_or_default();
        AppStateRest {
            mode: AgentMode::Normal,
            settings,
            workspace_roots,
            session_id,
            session_dir: session_dir.clone(),
            memory_dir,
            download_dir,
            worktrees_dir,
            turn_events: Arc::new(Mutex::new(VecDeque::new())),
            turn_in_flight: Arc::new(Mutex::new(false)),
            dir_cache: Arc::new(RwLock::new(dir_cache)),
            edit_log: EditLog::new(&session_dir),
            session_runtime: Some(SessionRuntime::new(session_dir.clone())),
            workflow_engine: WorkflowEngine::new(),
            mcp_manager: McpManager::new(),
            sessions: Vec::new(),
            transcript_cache: TranscriptCache::new(200),
            scroll: ScrollState::new(),
            input: InputState::new(),
            misc: MiscState::new(),
            dirty: true,
            quit: false,
        }
    }

    pub fn turn_in_flight(&self) -> bool {
        self.turn_in_flight.lock().map(|g| *g).unwrap_or(false)
    }

    pub fn set_mode(&mut self, mode: AgentMode) {
        self.mode = mode;
        self.dirty = true;
    }

    pub fn push_transcript(&mut self, msg: ChatMessageDisplay) {
        self.transcript_cache.messages.push(msg);
        if self.transcript_cache.messages.len() > self.transcript_cache.max_lines {
            self.transcript_cache.messages.remove(0);
        }
        self.transcript_cache.dirty = true;
        self.dirty = true;
    }

    pub fn push_toast(&mut self, toast: Toast) {
        self.misc.push_toast(toast);
        self.dirty = true;
    }

    pub fn store_base_dir(&self) -> std::path::PathBuf {
        self.session_dir.parent()
            .and_then(|p| p.parent())
            .map(|p| p.to_path_buf())
            .unwrap_or_else(|| self.session_dir.parent()
                .map(|p| p.to_path_buf())
                .unwrap_or_else(|| self.session_dir.clone()))
    }

    pub fn tool_ctx(&self) -> crate::tool::ToolCtx {
        self.tool_ctx_for(Origin::Main)
    }

    pub fn tool_ctx_for(&self, origin: Origin) -> crate::tool::ToolCtx {
        crate::tool::ToolCtx {
            workspaces: self.workspace_roots.clone(),
            session_dir: self.session_dir.clone(),
            memory_dir: self.memory_dir.clone(),
            _download_dir: self.download_dir.clone(),
            worktrees_dir: self.worktrees_dir.clone(),
            dir_cache: self.dir_cache.clone(),
            internet_mode: self.settings.internet_mode.clone(),
            origin,
            graduated_checks: Vec::new(),
        }
    }
}