mod ai;
pub mod camera;
mod components;
mod damage_system;
mod game_log;
mod gamesystem;
mod gui;
mod hunger_system;
mod inventory_system;
mod lighting_system;
mod map;
pub mod map_builders;
mod map_indexing_system;
mod melee_combat_system;
mod particle_system;
mod player;
pub mod random_table;
pub mod raws;
mod rect;
mod rex_assets;
pub mod saveload_system;
mod spawner;
mod trigger_system;
mod visibility_system;

#[macro_use]
extern crate lazy_static;

use ::rltk::{GameState, Point, RandomNumberGenerator, Rltk};
use ::specs::prelude::*;
use ::specs::saveload::{SimpleMarker, SimpleMarkerAllocator};
use components::*;
use damage_system::DamageSystem;
pub use game_log::GameLog;
use gui::{show_cheat_mode, CheatMenuResult};
use hunger_system::HungerSystem;
use inventory_system::{ItemCollectionSystem, ItemDropSystem, ItemRemoveSystem, ItemUseSystem};
use lighting_system::LightingSystem;
pub use map::*;
use map_indexing_system::MapIndexingSystem;
use melee_combat_system::MeleeCombatSystem;
use particle_system::ParticleSpawnSystem;
use player::*;
pub use rect::Rect;
use trigger_system::TriggerSystem;
use visibility_system::VisibilitySystem;

/// Cut down on the amount of syntax to register components
macro_rules! register {
    // $gs is needed to get the scope at the usage point
    // $Type is the Component type that is being registered
    ($gs: ident <- $( $Type: ty ),*,) => {
        $(
            $gs.ecs.register::<$Type>();
        )*
    }
}

const SHOW_MAPGEN_VISUALIZER: bool = false;

#[derive(PartialEq, Copy, Clone)]
pub enum RunState {
    AwaitingInput,
    PreRun,
    PlayerTurn,
    MonsterTurn,
    ShowInventory,
    ShowDropItem,
    ShowTargeting {
        range: i32,
        item: Entity,
    },
    MainMenu {
        menu_selection: gui::MainMenuSelection,
    },
    SaveGame,
    NextLevel,
    PreviousLevel,
    ShowRemoveItem,
    GameOver,
    MagicMapReveal {
        row: i32,
    },
    MapGeneration,
    ShowCheatMenu,
}

pub struct State {
    pub ecs: World,
    mapgen_next_state: Option<RunState>,
    mapgen_history: Vec<Map>,
    mapgen_index: usize,
    mapgen_timer: f32,
}

impl State {
    fn new() -> Self {
        State {
            ecs: World::new(),
            mapgen_next_state: Some(RunState::MainMenu {
                menu_selection: gui::MainMenuSelection::NewGame,
            }),
            mapgen_index: 0,
            mapgen_history: Vec::new(),
            mapgen_timer: 0.0,
        }
    }

    fn run_systems(&mut self) {
        let mut vis = VisibilitySystem {};
        vis.run_now(&self.ecs);

        let mut mob = ai::MonsterAI {};
        mob.run_now(&self.ecs);

        let mut mapindex = MapIndexingSystem {};
        mapindex.run_now(&self.ecs);

        let mut animal = ai::AnimalAI {};
        animal.run_now(&self.ecs);

        let mut bystander = ai::BystanderAI {};
        bystander.run_now(&self.ecs);

        let mut triggers = TriggerSystem {};
        triggers.run_now(&self.ecs);

        let mut melee = MeleeCombatSystem {};
        melee.run_now(&self.ecs);

        let mut damage = DamageSystem {};
        damage.run_now(&self.ecs);

        let mut pickup = ItemCollectionSystem {};
        pickup.run_now(&self.ecs);

        let mut items = ItemUseSystem {};
        items.run_now(&self.ecs);

        let mut drop_items = ItemDropSystem {};
        drop_items.run_now(&self.ecs);

        let mut item_remove = ItemRemoveSystem {};
        item_remove.run_now(&self.ecs);

        let mut hunger = HungerSystem {};
        hunger.run_now(&self.ecs);

        let mut particles = ParticleSpawnSystem {};
        particles.run_now(&self.ecs);

        let mut lighting = LightingSystem {};
        lighting.run_now(&self.ecs);

        self.ecs.maintain();
    }
}

impl GameState for State {
    fn tick(&mut self, ctx: &mut Rltk) {
        let mut newrunstate;
        {
            let runstate = self.ecs.fetch::<RunState>();
            newrunstate = *runstate;
        }

        ctx.cls();
        particle_system::cull_dead_particles(&mut self.ecs, ctx);

        match newrunstate {
            RunState::MainMenu { .. } => {}
            RunState::GameOver { .. } => {}
            _ => {
                camera::render_camera(&self.ecs, ctx);
                gui::draw_ui(&self.ecs, ctx);
            }
        }

        match newrunstate {
            RunState::MapGeneration => {
                if !SHOW_MAPGEN_VISUALIZER {
                    newrunstate = self.mapgen_next_state.unwrap();
                }
                ctx.cls();
                if self.mapgen_index < self.mapgen_history.len() {
                    camera::render_debug_map(&self.mapgen_history[self.mapgen_index], ctx);
                }

                self.mapgen_timer += ctx.frame_time_ms;
                if self.mapgen_timer > 300.0 {
                    self.mapgen_timer = 0.0;
                    self.mapgen_index += 1;
                    if self.mapgen_index >= self.mapgen_history.len() {
                        newrunstate = self.mapgen_next_state.unwrap();
                    }
                }
            }
            RunState::PreRun => {
                self.run_systems();
                self.ecs.maintain();
                newrunstate = RunState::AwaitingInput;
            }
            RunState::AwaitingInput => {
                newrunstate = player_input(self, ctx);
            }
            RunState::PlayerTurn => {
                self.run_systems();
                self.ecs.maintain();

                match *self.ecs.fetch::<RunState>() {
                    RunState::MagicMapReveal { .. } => {
                        newrunstate = RunState::MagicMapReveal { row: 0 }
                    }
                    _ => newrunstate = RunState::MonsterTurn,
                }
            }
            RunState::MonsterTurn => {
                self.run_systems();
                self.ecs.maintain();
                newrunstate = RunState::AwaitingInput;
            }
            RunState::ShowInventory => {
                let result = gui::show_inventory(self, ctx);
                match result.0 {
                    gui::ItemMenuResult::Cancel => newrunstate = RunState::AwaitingInput,
                    gui::ItemMenuResult::NoResponse => {}
                    gui::ItemMenuResult::Selected => {
                        let item_entity = result.1.unwrap();
                        let is_ranged = self.ecs.read_storage::<Ranged>();

                        if let Some(is_item_ranged) = is_ranged.get(item_entity) {
                            newrunstate = RunState::ShowTargeting {
                                range: is_item_ranged.range,
                                item: item_entity,
                            };
                        } else {
                            let mut intent = self.ecs.write_storage::<WantsToUseItem>();
                            intent
                                .insert(
                                    *self.ecs.fetch::<Entity>(),
                                    WantsToUseItem {
                                        item: item_entity,
                                        target: None,
                                    },
                                )
                                .expect("failed to add intent to use item");

                            newrunstate = RunState::PlayerTurn;
                        }
                    }
                }
            }
            RunState::ShowDropItem => {
                let result = gui::drop_item_menu(self, ctx);
                match result.0 {
                    gui::ItemMenuResult::Cancel => newrunstate = RunState::AwaitingInput,
                    gui::ItemMenuResult::NoResponse => {}
                    gui::ItemMenuResult::Selected => {
                        let item_entity = result.1.unwrap();
                        let mut intent = self.ecs.write_storage::<WantsToDropItem>();
                        intent
                            .insert(
                                *self.ecs.fetch::<Entity>(),
                                WantsToDropItem { item: item_entity },
                            )
                            .expect("failed to add intent to drop item");

                        newrunstate = RunState::PlayerTurn;
                    }
                }
            }
            RunState::ShowRemoveItem => {
                let result = gui::remove_item_menu(self, ctx);
                match result.0 {
                    gui::ItemMenuResult::Cancel => newrunstate = RunState::AwaitingInput,
                    gui::ItemMenuResult::NoResponse => {}
                    gui::ItemMenuResult::Selected => {
                        let item_entity = result.1.unwrap();
                        let mut intent = self.ecs.write_storage::<WantsToRemoveItem>();
                        intent
                            .insert(
                                *self.ecs.fetch::<Entity>(),
                                WantsToRemoveItem { item: item_entity },
                            )
                            .expect("Unable to insert intent to remove item");

                        newrunstate = RunState::PlayerTurn;
                    }
                }
            }
            RunState::ShowTargeting { range, item } => {
                let result = gui::ranged_target(self, ctx, range);
                match result.0 {
                    gui::ItemMenuResult::Cancel => newrunstate = RunState::AwaitingInput,
                    gui::ItemMenuResult::NoResponse => {}
                    gui::ItemMenuResult::Selected => {
                        let mut intent = self.ecs.write_storage::<WantsToUseItem>();

                        intent
                            .insert(
                                *self.ecs.fetch::<Entity>(),
                                WantsToUseItem {
                                    item,
                                    target: result.1,
                                },
                            )
                            .expect("failed to add intent to use item");

                        newrunstate = RunState::PlayerTurn;
                    }
                }
            }
            RunState::MainMenu { .. } => match gui::main_menu(self, ctx) {
                gui::MainMenuResult::NoSelection { selected } => {
                    newrunstate = RunState::MainMenu {
                        menu_selection: selected,
                    }
                }
                gui::MainMenuResult::Selected { selected } => match selected {
                    gui::MainMenuSelection::NewGame => newrunstate = RunState::PreRun,
                    gui::MainMenuSelection::LoadGame => {
                        saveload_system::load_game(&mut self.ecs);
                        newrunstate = RunState::AwaitingInput;
                        saveload_system::delete_save();
                    }
                    gui::MainMenuSelection::Quit => {
                        ::std::process::exit(0);
                    }
                },
            },
            RunState::GameOver => match gui::game_over(ctx) {
                gui::GameOverResult::NoSelection => {}
                gui::GameOverResult::QuitToMenu => {
                    self.game_over_cleanup();
                    newrunstate = RunState::MainMenu {
                        menu_selection: gui::MainMenuSelection::NewGame,
                    };
                }
            },
            RunState::SaveGame => {
                saveload_system::save_game(&mut self.ecs);

                newrunstate = RunState::MainMenu {
                    menu_selection: gui::MainMenuSelection::LoadGame,
                }
            }
            RunState::NextLevel => {
                self.goto_level(1);
                newrunstate = RunState::PreRun;
            }
            RunState::PreviousLevel => {
                self.goto_level(-1);
                self.mapgen_next_state = Some(RunState::PreRun);
                newrunstate = RunState::MapGeneration;
            }
            RunState::MagicMapReveal { row } => {
                let mut map = self.ecs.fetch_mut::<Map>();
                for x in 0..map.width {
                    let idx = map.xy_idx(x as i32, row);
                    map.revealed_tiles[idx] = true;
                }

                if row == map.height - 1 {
                    newrunstate = RunState::MonsterTurn;
                } else {
                    newrunstate = RunState::MagicMapReveal { row: row + 1 };
                }
            }
            RunState::ShowCheatMenu => match show_cheat_mode(self, ctx) {
                CheatMenuResult::Cancel => newrunstate = RunState::AwaitingInput,
                CheatMenuResult::NoResponse => {}
                CheatMenuResult::TeleportToExit => {
                    self.goto_level(1);
                    self.mapgen_next_state = Some(RunState::PreRun);
                    newrunstate = RunState::MapGeneration
                }
            },
        }

        {
            let mut runwriter = self.ecs.write_resource::<RunState>();
            *runwriter = newrunstate;
        }

        damage_system::delete_the_dead(&mut self.ecs);
    }
}

impl State {
    fn goto_level(&mut self, offset: i32) {
        freeze_level_entities(&mut self.ecs);

        // Build a new map and place the player
        let current_depth = self.ecs.fetch::<Map>().depth;
        self.generate_world_map(current_depth + offset, offset);

        // Notify the player
        let mut gamelog = self.ecs.fetch_mut::<GameLog>();
        gamelog.append("You change level.");
    }

    fn game_over_cleanup(&mut self) {
        // Delete everything
        let mut to_delete = Vec::new();
        for e in self.ecs.entities().join() {
            to_delete.push(e);
        }
        for del in to_delete.iter() {
            self.ecs
                .delete_entity(*del)
                .expect("Failed to delete entity");
        }

        // Spawn a new player
        {
            let player_entity = spawner::player(&mut self.ecs, 0, 0);
            let mut player_entity_writer = self.ecs.write_resource::<Entity>();
            *player_entity_writer = player_entity;
        }

        // Replace the world maps
        self.ecs.insert(map::MasterDungeonMap::new());

        // Build a new map and place the player
        self.generate_world_map(1, 0);
    }

    fn generate_world_map(&mut self, new_depth: i32, offset: i32) {
        self.mapgen_index = 0;
        self.mapgen_timer = 0.0;
        self.mapgen_history.clear();

        if let Some(history) = map::level_transition(&mut self.ecs, new_depth, offset) {
            self.mapgen_history = history;
        } else {
            map::thaw_level_entities(&mut self.ecs);
        }
    }
}

fn main() -> ::rltk::BError {
    let context = ::rltk::RltkBuilder::simple(80, 60)
        .unwrap()
        .with_title("Roguelike Tutorial")
        .build()?;

    let mut gs = State::new();

    register!(
        gs <-
        AreaOfEffect,
        Attributes,
        BlocksTile,
        BlocksVisibility,
        Bystander,
        Carnivore,
        Confusion,
        Consumable,
        Door,
        DMSerializationHelper,
        EntityMoved,
        EntryTrigger,
        Equippable,
        Equipped,
        Herbivore,
        Hidden,
        HungerClock,
        InBackpack,
        InflictsDamage,
        Initiative,
        Item,
        LightSource,
        LootTable,
        MagicMapper,
        MeleeWeapon,
        Monster,
        Name,
        NaturalAttackDefense,
        OtherLevelPosition,
        ParticleLifetime,
        Player,
        Pools,
        Position,
        ProvidesFood,
        ProvidesHealing,
        Quips,
        Ranged,
        Renderable,
        SerializationHelper,
        SimpleMarker<SerializeMe>,
        SingleActivation,
        Skills,
        SufferDamage,
        Vendor,
        Viewshed,
        WantsToDropItem,
        WantsToMelee,
        WantsToPickupItem,
        WantsToRemoveItem,
        WantsToUseItem,
        Wearable,
    );

    gs.ecs.insert(SimpleMarkerAllocator::<SerializeMe>::new());

    raws::load_raws();

    gs.ecs.insert(map::MasterDungeonMap::new());
    gs.ecs.insert(Map::new(1, 64, 64, "New Map"));
    gs.ecs.insert(Point::zero());
    gs.ecs.insert(RandomNumberGenerator::new());

    let player_entity = spawner::player(&mut gs.ecs, 0, 0);
    gs.ecs.insert(player_entity);

    gs.ecs.insert(RunState::MapGeneration {});
    gs.ecs.insert(GameLog::new("Welcome to Rusty Roguelike"));
    gs.ecs.insert(particle_system::ParticleBuilder::new());
    gs.ecs.insert(rex_assets::RexAssets::new());

    gs.generate_world_map(1, 0);

    rltk::main_loop(context, gs)
}