use crate::ai::blocklist::InputConfig;
use crate::context_chips::prompt_type::PromptType;
use crate::pane_group::TerminalViewResources;
use crate::persistence::ModelEvent;
use crate::terminal::event_listener::ChannelEventListener;
use crate::terminal::model::session::Sessions;
use crate::terminal::remote_tty::event_loop::EventLoop;
use crate::terminal::shell::{ShellName, ShellType};
use crate::terminal::writeable_pty::pty_controller::{EventLoopSendError, EventLoopSender};
use crate::terminal::writeable_pty::terminal_manager_util::{
    init_pty_controller_model, wire_up_pty_controller_with_view,
};
use crate::terminal::ShellLaunchState;
use std::any::Any;

use crate::terminal::model_events::ModelEventDispatcher;
use crate::terminal::writeable_pty::{self, Message};
use crate::terminal::{terminal_manager, SizeInfo, TerminalModel, TerminalView};
use async_channel::{Receiver, Sender, TrySendError};
use galaxyui::{AppContext, ModelHandle, ViewHandle, WindowId};
use parking_lot::FairMutex;
use pathfinder_geometry::vector::Vector2F;
use std::sync::mpsc::SyncSender;
use std::sync::Arc;

type PtyController = writeable_pty::PtyController<Sender<Message>>;

pub struct TerminalManager {
    model: Arc<FairMutex<TerminalModel>>,

    // Store a reference to the PTYController and EventLoop so the UI framework doesn't end up
    // deallocating them because there are no strong references to the models.
    _pty_controller: ModelHandle<PtyController>,

    _event_loop: ModelHandle<EventLoop>,

    view: ViewHandle<TerminalView>,
}

impl TerminalManager {
    /// Creates a terminal manager model that feeds bytes to/from a remote PTY.
    pub fn create_model(
        resources: TerminalViewResources,
        initial_size: Vector2F,
        model_event_sender: Option<SyncSender<ModelEvent>>,
        window_id: WindowId,
        initial_input_config: Option<InputConfig>,
        ctx: &mut AppContext,
    ) -> ModelHandle<Box<dyn crate::terminal::TerminalManager>> {
        // Create all the necessary channels we need for communication.
        let (wakeups_tx, wakeups_rx) = async_channel::unbounded();
        let (events_tx, events_rx) = async_channel::unbounded();
        let (executor_command_tx, executor_command_rx) = async_channel::unbounded();

        // Use an empty pty reads broadcaster since we don't need to broadcast any PTY bytes for the
        // network-backed PTY. We use 1 instead of 0 here because `async_broadcast` internally
        // asserts that the capacity is at least 1.
        let (pty_reads_tx, _pty_reads_rx) = async_broadcast::broadcast(1);

        let channel_event_proxy = ChannelEventListener::new(wakeups_tx, events_tx, pty_reads_tx);

        // Initialize the sessions model.
        let sessions: ModelHandle<Sessions> =
            ctx.add_model(|ctx| Sessions::new(executor_command_tx, ctx));

        let model_events =
            ctx.add_model(|ctx| ModelEventDispatcher::new(events_rx, sessions.clone(), ctx));

        // Create the terminal model.
        let model = terminal_manager::create_terminal_model(
            None, /* startup_directory */
            None, /* restored_blocks */
            initial_size,
            channel_event_proxy.clone(),
            // TODO(alokedesai): Add support for other shells within the network-backed pty.
            ShellLaunchState::ShellSpawned {
                available_shell: None,
                display_name: ShellName::blank(),
                shell_type: ShellType::Zsh,
            },
            ctx,
        );

        let size_info = *model.block_list().size();
        let colors = model.colors();
        let model = Arc::new(FairMutex::new(model));

        let (event_loop_tx, event_loop_rx) = async_channel::unbounded();

        let event_loop = Self::create_and_start_event_loop(
            model.clone(),
            channel_event_proxy.clone(),
            event_loop_rx,
            size_info,
            ctx,
        );

        // Initialize the PtyController.
        let pty_controller = init_pty_controller_model(
            event_loop_tx.clone(),
            executor_command_rx,
            model_events.clone(),
            sessions.clone(),
            model.clone(),
            ctx,
        );

        let cloned_model = model.clone();
        let prompt_type =
            ctx.add_model(|ctx| PromptType::new_dynamic_from_sessions(sessions.clone(), ctx));
        let view = ctx.add_typed_action_view(window_id, |ctx| {
            TerminalView::new(
                resources,
                wakeups_rx,
                model_events.clone(),
                cloned_model,
                sessions.clone(),
                size_info,
                colors,
                model_event_sender.clone(),
                prompt_type,
                initial_input_config,
                None, // conversation_restoration - not used for remote
                None, // inactive_pty_reads_rx
                ctx,
            )
        });

        wire_up_pty_controller_with_view(
            &pty_controller,
            &view,
            model.clone(),
            sessions,
            model_event_sender,
            ctx,
        );

        // Create the terminal manager itself.
        let terminal_manager = Self {
            model,
            view,
            _pty_controller: pty_controller,
            _event_loop: event_loop,
        };

        ctx.add_model(|_ctx| {
            let manager: Box<dyn crate::terminal::TerminalManager> = Box::new(terminal_manager);
            manager
        })
    }

    fn create_and_start_event_loop(
        terminal_model: Arc<FairMutex<TerminalModel>>,
        channel_event_listener: ChannelEventListener,
        message_receiver: Receiver<Message>,
        size_info: SizeInfo,
        ctx: &mut AppContext,
    ) -> ModelHandle<EventLoop> {
        ctx.add_model(|ctx| {
            EventLoop::start(
                terminal_model,
                message_receiver,
                channel_event_listener,
                size_info,
                ctx,
            )
        })
    }
}

impl super::super::TerminalManager for TerminalManager {
    fn model(&self) -> Arc<FairMutex<TerminalModel>> {
        self.model.clone()
    }

    fn view(&self) -> ViewHandle<TerminalView> {
        self.view.clone()
    }

    fn as_any(&self) -> &dyn std::any::Any {
        self
    }

    fn as_any_mut(&mut self) -> &mut dyn Any {
        self
    }
}

impl EventLoopSender for Sender<Message> {
    fn send(&self, message: Message) -> Result<(), EventLoopSendError> {
        self.try_send(message).map_err(|err| match err {
            TrySendError::Closed(_) => EventLoopSendError::Disconnected,
            TrySendError::Full(_) => EventLoopSendError::Other(err.into()),
        })
    }
}