use super::{
    VerbContext, UserVerb, UserVerbRef, UResult, UserError, user_error,
    get_player_item_or_fail,
    look::direction_to_item,
};
use async_trait::async_trait;
use crate::{
    DResult,
    regular_tasks::{
        TaskRunContext,
        TaskHandler,
        queued_command::{
            QueueCommandHandler,
            QueueCommand,
            queue_command
        },
    },
    static_content::{
        room::Direction,
        possession_type::possession_data,
    },
    models::{
        item::{Item, LocationActionType, DoorState},
        task::{Task, TaskMeta, TaskDetails}
    },
    services::comms::broadcast_to_room,
};
use std::sync::Arc;
use std::time;
use chrono::{self, Utc};
use mockall_double::double;
#[double] use crate::db::DBTrans;

#[derive(Clone)]
pub struct SwingShutHandler;
pub static SWING_SHUT_HANDLER: &'static (dyn TaskHandler + Sync + Send) = &SwingShutHandler;

#[async_trait]
impl TaskHandler for SwingShutHandler {
    async fn do_task(&self, ctx: &mut TaskRunContext) -> DResult<Option<time::Duration>> {
        let (room_str, direction) = match &ctx.task.details {
            TaskDetails::SwingShut { room_item, direction } => (room_item, direction),
            _ => { return Ok(None); }
        };
        let (room_item_type, room_item_code) = match room_str.split_once("/") {
            None => { return Ok(None); },
            Some(v) => v
        };
        let room_item = match ctx.trans.find_item_by_type_code(room_item_type, room_item_code).await? {
            None => { return Ok(None); },
            Some(v) => v
        };

        let mut room_item_mut = (*room_item).clone();
        let mut door_state = match room_item_mut.door_states.as_mut().and_then(|ds| ds.get_mut(&direction)) {
            None => { return Ok(None); },
            Some(v) => v
        };
        (*door_state).open = false;
        ctx.trans.save_item_model(&room_item_mut).await?;

        let msg = format!("The door to the {} swings shut with a click.\n",
                          &direction.describe());
        broadcast_to_room(&ctx.trans, &room_str, None, &msg, Some(&msg)).await?;
        
        if let Ok(Some(other_room)) = direction_to_item(&ctx.trans, &room_str, &direction).await {
            let msg = format!("The door to the {} swings shut with a click.\n",
                              &direction.reverse().map(|d| d.describe()).unwrap_or_else(|| "outside".to_owned()));
            broadcast_to_room(&ctx.trans, &other_room.refstr(), None, &msg, Some(&msg)).await?;
        }
        
        Ok(None)
    }
}

pub async fn attempt_open_immediate(trans: &DBTrans, ctx_opt: &mut Option<&mut VerbContext<'_>>,
                                    who: &Item, direction: &Direction) -> UResult<()> {
    let use_location = if who.death_data.is_some() {
        user_error("Your ethereal hands don't seem to be able to move the door.".to_owned())?
    } else {
        &who.location
    };
    let (room_1, dir_in_room, room_2) = match is_door_in_direction(trans, &direction, use_location).await? {
        DoorSituation::NoDoor => user_error("There is no door to open.".to_owned())?,
        DoorSituation::DoorIntoRoom { state: DoorState { open: true, .. }, .. } |
        DoorSituation::DoorOutOfRoom { state: DoorState { open: true, .. }, .. } =>
            user_error("The door is already open.".to_owned())?,
        DoorSituation::DoorIntoRoom { room_with_door, current_room, .. } => {
            let entering_room_loc = room_with_door.refstr();
            if let Some(revdir) = direction.reverse() {
                if let Some(lock) = trans.find_by_action_and_location(
                    &entering_room_loc,
                    &LocationActionType::InstalledOnDoorAsLock(revdir.clone())).await?.first()
                {
                    if let Some(ctx) = ctx_opt {
                        if let Some(lockcheck) = lock.possession_type.as_ref()
                            .and_then(|pt| possession_data().get(pt))
                            .and_then(|pd| pd.lockcheck_handler) {
                                lockcheck.cmd(ctx, &who, &lock).await?
                            }
                    } else {
                        // NPCs don't unlock doors.
                        user_error("Can't get through locked doors".to_owned())?;
                    }
                }
                let mut entering_room_mut = (*room_with_door).clone();
                if let Some(door_map) = entering_room_mut.door_states.as_mut() {
                    if let Some(door) = door_map.get_mut(&revdir) {
                        (*door).open = true;
                    }
                }
                trans.save_item_model(&entering_room_mut).await?;
                (room_with_door, revdir, current_room)

            } else {
                user_error("There's no door possible there.".to_owned())?
            }
        },
        DoorSituation::DoorOutOfRoom { room_with_door, new_room, .. } => {
            let mut entering_room_mut = (*room_with_door).clone();
            if let Some(door_map) = entering_room_mut.door_states.as_mut() {
                if let Some(door) = door_map.get_mut(&direction) {
                    (*door).open = true;
                }
            }
            trans.save_item_model(&entering_room_mut).await?;
            (room_with_door, direction.clone(), new_room)
        }
    };

    for (loc, dir) in [(&room_1.refstr(), &dir_in_room.describe()),
                       (&room_2.refstr(), &dir_in_room.reverse().map(|d| d.describe())
                        .unwrap_or_else(|| "outside".to_owned()))] {
        broadcast_to_room(
            &trans,
            loc,
            None,
            &format!("{} opens the door to the {}.\n",
                     &who.display_for_sentence(true, 1, true),
                     dir
            ),
            Some(
                &format!("{} opens the door to the {}.\n",
                         &who.display_for_sentence(false, 1, true),
                         dir
                )
            )
        ).await?;
    }

    trans.upsert_task(&Task {
        meta: TaskMeta {
            task_code: format!("{}/{}", &room_1.refstr(), &direction.describe()),
            next_scheduled: Utc::now() + chrono::Duration::seconds(120),
            ..Default::default()
        },
        details: TaskDetails::SwingShut {
            room_item: room_1.refstr(),
            direction: dir_in_room.clone()
        }
    }).await?;
    
    Ok(())
}

pub struct QueueHandler;
#[async_trait]
impl QueueCommandHandler for QueueHandler {
    async fn start_command(&self, ctx: &mut VerbContext<'_>, command: &QueueCommand)
                           -> UResult<time::Duration> {
        let direction = match command {
            QueueCommand::OpenDoor { direction } => direction,
            _ => user_error("Unexpected command".to_owned())?
        };
        let player_item = get_player_item_or_fail(ctx).await?;        
        let use_location = if player_item.death_data.is_some() {
            user_error("Your ethereal hands don't seem to be able to move the door.".to_owned())?
        } else {
            &player_item.location
        };
        match is_door_in_direction(&ctx.trans, &direction, use_location).await? {
            DoorSituation::NoDoor => user_error("There is no door to open.".to_owned())?,
            DoorSituation::DoorIntoRoom { state: DoorState { open: true, .. }, .. } |
            DoorSituation::DoorOutOfRoom { state: DoorState { open: true, .. }, .. } =>
                user_error("The door is already open.".to_owned())?,
            DoorSituation::DoorIntoRoom { room_with_door: entering_room, .. } => {
                let entering_room_loc = entering_room.refstr();
                if let Some(revdir) = direction.reverse() {
                    if let Some(lock) = ctx.trans.find_by_action_and_location(
                        &entering_room_loc,
                        &LocationActionType::InstalledOnDoorAsLock(revdir)).await?.first()
                    {
                        if let Some(lockcheck) = lock.possession_type.as_ref()
                            .and_then(|pt| possession_data().get(pt))
                            .and_then(|pd| pd.lockcheck_handler) {
                                lockcheck.cmd(ctx, &player_item, &lock).await?
                            }
                    }
                }
            }
            _ => {}
        }
        
        Ok(time::Duration::from_secs(1))
    }

    #[allow(unreachable_patterns)]
    async fn finish_command(&self, ctx: &mut VerbContext<'_>, command: &QueueCommand)
                            -> UResult<()> {
        let direction = match command {
            QueueCommand::OpenDoor { direction } => direction,
            _ => user_error("Unexpected command".to_owned())?
        };
        let player_item = get_player_item_or_fail(ctx).await?;
        attempt_open_immediate(&ctx.trans, &mut Some(ctx), &player_item, &direction).await?;

        Ok(())
    }
}

pub enum DoorSituation {
    NoDoor,
    DoorIntoRoom { state: DoorState, room_with_door: Arc<Item>, current_room: Arc<Item> }, // Can be locked etc...
    DoorOutOfRoom { state: DoorState, room_with_door: Arc<Item>, new_room: Arc<Item> } // No lockable.
}

pub async fn is_door_in_direction(trans: &DBTrans, direction: &Direction, use_location: &str) ->
    UResult<DoorSituation> {
        let (loc_type_t, loc_type_c) = use_location.split_once("/")
            .ok_or_else(|| UserError("Invalid location".to_owned()))?;
        let cur_loc_item = trans.find_item_by_type_code(loc_type_t, loc_type_c).await?
            .ok_or_else(|| UserError("Can't find your current location anymore.".to_owned()))?;
        let new_loc_item = direction_to_item(trans, use_location, direction).await?
            .ok_or_else(|| UserError("That exit doesn't really seem to go anywhere!".to_owned()))?;
        if let Some(door_state) =
            cur_loc_item.door_states.as_ref()
            .and_then(|v| v.get(direction)) {
                return Ok(DoorSituation::DoorOutOfRoom {
                    state: door_state.clone(),
                    room_with_door: cur_loc_item,
                    new_room: new_loc_item
                });
            }
        if let Some(door_state) =
            new_loc_item.door_states.as_ref()
            .and_then(|v| direction.reverse().as_ref()
                      .and_then(|rev| v.get(rev).map(|door| door.clone()))) {
                return Ok(DoorSituation::DoorIntoRoom {
                    state: door_state.clone(),
                    room_with_door: new_loc_item,
                    current_room: cur_loc_item
                });
            }
        Ok(DoorSituation::NoDoor)
    }

pub struct Verb;

#[async_trait]
impl UserVerb for Verb {
    async fn handle(self: &Self, ctx: &mut VerbContext, _verb: &str, remaining: &str) -> UResult<()> {
        let dir = Direction::parse(remaining)
            .ok_or_else(|| UserError("Unknown direction".to_owned()))?;
        queue_command(ctx, &QueueCommand::OpenDoor { direction: dir.clone() }).await?;
        Ok(())
    }
}
static VERB_INT: Verb = Verb;
pub static VERB: UserVerbRef = &VERB_INT as UserVerbRef;