// DungeonCraft – dungeon building & defence in the browser (Rust + macroquad, WASM).

mod game;
mod gfx;
mod i18n;
mod map;
mod menu;
mod platform;
mod render3d;
mod save;
mod settings;
mod sound;
mod ui;

use game::{Game, Msg};
use gfx::Gfx;
use macroquad::prelude::*;
use map::{idx, inb, MH, MW};
use menu::{Menu, MenuAction, Page};
use render3d::{Cam, Overlay, R3d};
use settings::{bindable_keys, Action, Settings};
use sound::SoundBank;
use ui::{hover_info, Tool, Ui, UiAction, TOOLS};

const SETTINGS_KEY: &str = "dc.settings";
const AUTOSAVE_EVERY: f32 = 120.0; // seconds of play between autosaves
const AUTOSAVE_CACHE_EVERY: f32 = 15.0; // snapshot kept in JS, written when the tab is left

fn conf() -> macroquad::conf::Conf {
    macroquad::conf::Conf {
        miniquad_conf: miniquad::conf::Conf {
            window_title: "DungeonCraft".into(),
            window_width: 1280,
            window_height: 800,
            high_dpi: false,
            ..Default::default()
        },
        draw_call_vertex_capacity: 40000,
        draw_call_index_capacity: 60000,
        ..Default::default()
    }
}

struct Input {
    ldown: Option<(i32, i32)>, // start of the selection rectangle
    rdown: Option<(f32, f32)>, // right button press position
    rlast: (f32, f32),
    rdrag: bool,
    mlast: Option<(f32, f32)>, // middle button drag
    minimap_drag: bool,
}

fn new_game(seed: u32) -> (Game, Cam) {
    let g = Game::new(seed);
    let (cx, cy) = g.map.core;
    let cam = Cam::new(cx as f32 + 1.5, cy as f32 + 1.5);
    (g, cam)
}

fn next_seed(seed: u32) -> u32 {
    seed.wrapping_mul(1103515245).wrapping_add(12345) | 1
}

fn apply_settings(s: &Settings, r3d: &mut R3d, sounds: &mut SoundBank) {
    i18n::set_language(&s.language);
    ui::set_ui_scale(s.ui_scale as f32);
    r3d.outlines = s.outlines;
    r3d.set_wall_detail(s.wall_subdivisions());
    r3d.max_lights = s.max_lights as usize;
    sounds.volume = s.volume;
    sounds.muted = s.muted;
}

fn store_settings(s: &Settings) {
    platform::storage_set(SETTINGS_KEY, &s.to_json());
}

// "dungeoncraft_2026-11-02_2145.dcsave" (UTC)
fn save_file_name() -> String {
    let secs = miniquad::date::now() as i64;
    let days = secs.div_euclid(86400);
    let rem = secs.rem_euclid(86400);
    // civil date from days since 1970-01-01 (Howard Hinnant's algorithm)
    let z = days + 719468;
    let era = z.div_euclid(146097);
    let doe = z - era * 146097;
    let yoe = (doe - doe / 1460 + doe / 36524 - doe / 146096) / 365;
    let doy = doe - (365 * yoe + yoe / 4 - yoe / 100);
    let mp = (5 * doy + 2) / 153;
    let d = doy - (153 * mp + 2) / 5 + 1;
    let m = if mp < 10 { mp + 3 } else { mp - 9 };
    let y = yoe + era * 400 + if m <= 2 { 1 } else { 0 };
    format!("dungeoncraft_{:04}-{:02}-{:02}_{:02}{:02}.dcsave", y, m, d, rem / 3600, rem % 3600 / 60)
}

struct App {
    game: Game,
    cam: Cam,
    settings: Settings,
    seed: u32,
    status: Option<(String, f64)>,
}

impl App {
    fn set_status(&mut self, text: String, now: f64) {
        self.status = Some((text, now));
    }

    // Load a savegame (settings in the savegame are always applied)
    fn load_bytes(&mut self, bytes: &[u8], ui: &mut Ui, menu: &mut Menu, r3d: &mut R3d, sounds: &mut SoundBank, now: f64) {
        match save::from_bytes(bytes) {
            Ok(l) => {
                self.game = l.game;
                if let Some(c) = l.camera {
                    self.cam = c;
                }
                if let Some(s) = l.settings {
                    self.settings = s;
                    apply_settings(&self.settings, r3d, sounds);
                    store_settings(&self.settings);
                }
                self.game.hints = self.settings.hints;
                r3d.invalidate();
                menu.page = None;
                ui.show_help = false;
                ui.log.clear();
                ui.log.push((Msg { key: "save.loaded", args: vec![] }, now));
                self.status = None;
            }
            Err(key) => self.set_status(i18n::tr(key), now),
        }
    }

    fn autosave_json(&self) -> String {
        save::to_json(&self.game, &self.cam, &self.settings)
    }
}

#[macroquad::main(conf)]
async fn main() {
    let gfx = Gfx::new();
    let mut r3d = R3d::new();
    let mut sounds = SoundBank::new();
    sounds.generate_all().await;
    let mut ui = Ui::new();
    let mut menu = Menu::new();

    // settings: stored in the browser; on the very first start the player picks a language
    let stored = platform::storage_get(SETTINGS_KEY).and_then(|s| Settings::from_json(&s));
    let mut settings = stored.clone().unwrap_or_default();
    if stored.is_none() {
        match platform::storage_get("dc.lang") {
            Some(code) => settings.language = code,
            None => ui.show_langsel = true,
        }
    }
    apply_settings(&settings, &mut r3d, &mut sounds);
    ui.show_help = false;
    menu.has_autosave = platform::storage_get(save::AUTOSAVE_KEY).is_some();

    let seed = (miniquad::date::now() * 1000.0) as u32 | 1;
    let (game, cam) = new_game(seed);
    let mut app = App { game, cam, settings, seed, status: None };
    app.game.hints = app.settings.hints;
    let mut inp = Input { ldown: None, rdown: None, rlast: (0.0, 0.0), rdrag: false, mlast: None, minimap_drag: false };
    let mut autosave_t = 0.0f32;
    let mut cache_t = 0.0f32;

    loop {
        let dt = get_frame_time().min(0.1);
        let now = get_time();
        let (mx, my) = mouse_position();
        let mut settings_changed = false;

        // ---------------- savegame files: file picker result or dropped onto the window
        let mut incoming: Option<Vec<u8>> = platform::take_file();
        for f in get_dropped_files() {
            if let Some(b) = f.bytes {
                incoming = Some(b);
            }
        }
        if let Some(bytes) = incoming {
            app.load_bytes(&bytes, &mut ui, &mut menu, &mut r3d, &mut sounds, now);
        }

        // ---------------- key capture for the key binding dialog
        if let Some(action) = menu.capturing() {
            if is_key_pressed(KeyCode::Escape) {
                menu.finish_capture();
            } else if let Some(k) = get_last_key_pressed() {
                if bindable_keys().any(|b| b == k) {
                    app.settings.bind(action, k);
                    apply_settings(&app.settings, &mut r3d, &mut sounds);
                    store_settings(&app.settings);
                    menu.finish_capture();
                }
            }
            draw_frame(&mut app, &gfx, &mut r3d, &mut ui, &mut menu, &sounds, &inp, now);
            next_frame().await;
            continue;
        }

        let dialog = ui.show_langsel || ui.show_help;
        let in_menu = menu.open();
        let playing = !in_menu && !dialog;
        let over_ui = ui.over_ui(mx, my);
        let picked = app.cam.pick_tile(&app.game.map, mx, my);
        let hover_tile = picked.map(|(x, z, _)| (x, z));
        let ground = app.cam.ground_point(mx, my);
        let (wx, wy) = (ground.x, ground.y);
        let keys = app.settings.clone();
        let key = |a: Action| keys.key(a);

        // ---------------- Esc: dialogs, menus, pause menu
        if is_key_pressed(KeyCode::Escape) {
            if ui.show_langsel {
            } else if ui.show_help {
                ui.show_help = false;
            } else if in_menu {
                menu.back();
            } else if inp.ldown.is_some() {
                inp.ldown = None;
            } else {
                menu.page = Some(Page::Pause);
            }
        }

        // ---------------- keyboard (only while playing)
        if playing {
            for i in 0..TOOLS.len() {
                if is_key_pressed(key(Action::Tool(i))) {
                    ui.tool = TOOLS[i];
                    inp.ldown = None;
                }
            }
            if is_key_pressed(key(Action::Help)) {
                ui.show_help = true;
            }
            if is_key_pressed(key(Action::Pause)) && app.game.state == 0 {
                app.game.paused = !app.game.paused;
            }
            if is_key_pressed(key(Action::Outlines)) {
                app.settings.outlines = !app.settings.outlines;
                settings_changed = true;
            }
            if is_key_pressed(KeyCode::N) && app.game.state != 0 {
                app.seed = next_seed(app.seed);
                (app.game, app.cam) = new_game(app.seed);
                app.game.hints = app.settings.hints;
            }
        }
        if !dialog {
            if is_key_pressed(key(Action::Mute)) {
                app.settings.muted = !app.settings.muted;
                settings_changed = true;
            }
            if is_key_pressed(key(Action::VolumeUp)) || is_key_pressed(KeyCode::KpAdd) {
                app.settings.volume = (app.settings.volume + 0.1).min(1.0);
                settings_changed = true;
            }
            if is_key_pressed(key(Action::VolumeDown)) || is_key_pressed(KeyCode::KpSubtract) {
                app.settings.volume = (app.settings.volume - 0.1).max(0.0);
                settings_changed = true;
            }
        }

        // ---------------- camera
        if playing {
            let cam = &mut app.cam;
            let (right, fwd) = cam.ground_axes();
            let pan = cam.zoom * 0.9 * dt;
            let move_cam = |dx: f32, dz: f32, cam: &mut Cam| {
                let d = right * dx + fwd * dz;
                cam.tx += d.x;
                cam.tz += d.y;
            };
            if is_key_down(key(Action::CamForward)) || is_key_down(KeyCode::Up) {
                move_cam(0.0, pan, cam);
            }
            if is_key_down(key(Action::CamBack)) || is_key_down(KeyCode::Down) {
                move_cam(0.0, -pan, cam);
            }
            if is_key_down(key(Action::CamLeft)) || is_key_down(KeyCode::Left) {
                move_cam(-pan, 0.0, cam);
            }
            if is_key_down(key(Action::CamRight)) || is_key_down(KeyCode::Right) {
                move_cam(pan, 0.0, cam);
            }
            let edge = 6.0;
            if keys.edge_scroll && mx >= 0.0 && my >= 0.0 && mx < screen_width() && my < screen_height() {
                if mx < edge {
                    move_cam(-pan, 0.0, cam);
                } else if mx > screen_width() - edge {
                    move_cam(pan, 0.0, cam);
                }
                if my < edge {
                    move_cam(0.0, pan, cam);
                } else if my > screen_height() - edge {
                    move_cam(0.0, -pan, cam);
                }
            }
            let rot = 1.8 * dt * keys.rotate_speed;
            if is_key_down(key(Action::RotateLeft)) {
                cam.yaw += rot;
            }
            if is_key_down(key(Action::RotateRight)) {
                cam.yaw -= rot;
            }
            if is_key_down(key(Action::TiltUp)) {
                cam.pitch += rot * 0.6;
            }
            if is_key_down(key(Action::TiltDown)) {
                cam.pitch -= rot * 0.6;
            }
            if is_mouse_button_down(MouseButton::Middle) {
                if let Some((lx, ly)) = inp.mlast {
                    let inv = if keys.invert_mouse { -1.0 } else { 1.0 };
                    cam.yaw -= (mx - lx) * 0.008 * keys.rotate_speed * inv;
                    cam.pitch += (my - ly) * 0.005 * keys.rotate_speed * inv;
                }
                inp.mlast = Some((mx, my));
            } else {
                inp.mlast = None;
            }
            cam.pitch = cam.pitch.clamp(0.35, 1.45);
            let (_, wheel) = mouse_wheel();
            if wheel != 0.0 && !over_ui {
                let before = cam.ground_point(mx, my);
                let f = 0.88f32.powf(keys.zoom_speed);
                cam.zoom = (cam.zoom * if wheel > 0.0 { f } else { 1.0 / f }).clamp(6.0, 45.0);
                let after = cam.ground_point(mx, my);
                cam.tx += before.x - after.x;
                cam.tz += before.y - after.y;
            }
            // right button: drag = pan, click = drop
            if is_mouse_button_pressed(MouseButton::Right) {
                inp.rdown = Some((mx, my));
                inp.rlast = (mx, my);
                inp.rdrag = false;
            }
            if let Some((sx, sy)) = inp.rdown {
                if is_mouse_button_down(MouseButton::Right) {
                    if (mx - sx).abs() + (my - sy).abs() > 5.0 {
                        inp.rdrag = true;
                    }
                    if inp.rdrag {
                        let a = cam.ground_point(inp.rlast.0, inp.rlast.1);
                        let b = cam.ground_point(mx, my);
                        cam.tx -= b.x - a.x;
                        cam.tz -= b.y - a.y;
                    }
                    inp.rlast = (mx, my);
                }
            }
            if is_mouse_button_released(MouseButton::Right) {
                if !inp.rdrag && !over_ui && app.game.state == 0 {
                    if inp.ldown.is_some() {
                        inp.ldown = None;
                    } else {
                        app.game.drop(wx, wy);
                    }
                }
                inp.rdown = None;
            }
        }

        // ---------------- left button
        if is_mouse_button_pressed(MouseButton::Left) {
            if dialog {
                match ui.click(mx, my, &app.game) {
                    UiAction::SelectLanguage(code) => {
                        app.settings.language = code;
                        settings_changed = true;
                        ui.show_langsel = false;
                    }
                    UiAction::CloseHelp => ui.show_help = false,
                    _ => {}
                }
            } else if in_menu {
                match menu.click(mx, my, &mut app.settings) {
                    MenuAction::SettingsChanged => settings_changed = true,
                    MenuAction::Resume => {}
                    MenuAction::NewGame => {
                        app.seed = next_seed(app.seed);
                        (app.game, app.cam) = new_game(app.seed);
                        app.game.hints = app.settings.hints;
                        menu.page = None;
                        ui.log.clear();
                        ui.show_help = true;
                        autosave_t = 0.0;
                    }
                    MenuAction::Continue => {
                        if let Some(s) = platform::storage_get(save::AUTOSAVE_KEY) {
                            app.load_bytes(s.as_bytes(), &mut ui, &mut menu, &mut r3d, &mut sounds, now);
                        }
                    }
                    MenuAction::Load => {
                        platform::open_file();
                        app.set_status(i18n::tr("save.choose"), now);
                    }
                    MenuAction::Save => {
                        let name = save_file_name();
                        platform::download(&name, app.autosave_json().as_bytes());
                        app.set_status(i18n::trf("save.saved", &[name]), now);
                    }
                    MenuAction::Help => ui.show_help = true,
                    MenuAction::MainMenu => {
                        if app.game.state == 0 {
                            platform::storage_set(save::AUTOSAVE_KEY, &app.autosave_json());
                            menu.has_autosave = true;
                        }
                        menu.page = Some(Page::Title);
                    }
                    MenuAction::None | MenuAction::Consumed => {}
                }
            } else {
                match ui.click(mx, my, &app.game) {
                    UiAction::SelectTool(t) => {
                        ui.tool = t;
                        app.game.sfx_ui(game::Sfx::Click);
                    }
                    UiAction::MinimapJump(x, y) => {
                        app.cam.tx = x;
                        app.cam.tz = y;
                        inp.minimap_drag = true;
                    }
                    UiAction::NewGame => {
                        app.seed = next_seed(app.seed);
                        (app.game, app.cam) = new_game(app.seed);
                        app.game.hints = app.settings.hints;
                    }
                    UiAction::CloseHelp | UiAction::SelectLanguage(_) | UiAction::Consumed => {}
                    UiAction::None => {
                        if app.game.state == 0 {
                            match (ui.tool, hover_tile) {
                                (Tool::Dig | Tool::Room(_) | Tool::Sell, Some(t)) => inp.ldown = Some(t),
                                (Tool::Hand, _) => {
                                    let j = r3d.pick_ent(&app.game, &app.cam, mx, my, true);
                                    app.game.pickup(j);
                                }
                                (Tool::Flag, Some((x, z))) => app.game.set_flag(x, z),
                                (Tool::Lightning, _) => app.game.lightning(wx, wy),
                                (Tool::Heal, _) => app.game.heal(wx, wy),
                                (Tool::Summon, _) => app.game.summon(wx, wy),
                                _ => {}
                            }
                        }
                    }
                }
            }
        }
        if inp.minimap_drag {
            if is_mouse_button_down(MouseButton::Left) && ui.minimap_contains(mx, my) {
                let (x, y) = ui.minimap_world(mx, my);
                app.cam.tx = x;
                app.cam.tz = y;
            } else if !is_mouse_button_down(MouseButton::Left) {
                inp.minimap_drag = false;
            }
        }
        if is_mouse_button_released(MouseButton::Left) {
            if let Some((sx, sy)) = inp.ldown.take() {
                if let (true, Some((ex, ey))) = (playing, hover_tile) {
                    match ui.tool {
                        Tool::Dig => {
                            let on = !app.game.map.t[idx(sx, sy)].marked;
                            app.game.mark_rect(sx, sy, ex, ey, on);
                        }
                        Tool::Room(r) => app.game.build_rect(r, sx, sy, ex, ey),
                        Tool::Sell => app.game.sell_rect(sx, sy, ex, ey),
                        _ => {}
                    }
                }
            }
        }
        app.cam.tx = app.cam.tx.clamp(0.0, MW as f32);
        app.cam.tz = app.cam.tz.clamp(0.0, MH as f32);

        if settings_changed {
            apply_settings(&app.settings, &mut r3d, &mut sounds);
            store_settings(&app.settings);
            app.game.hints = app.settings.hints;
        }

        // ---------------- update (the world stands still while menus or dialogs are open)
        if playing {
            for _ in 0..(app.settings.game_speed.round().max(1.0) as usize) {
                app.game.update(dt);
            }
            // autosave: snapshot for leaving the tab + regular autosave
            if app.game.state == 0 {
                cache_t += dt;
                autosave_t += dt;
                if cache_t >= AUTOSAVE_CACHE_EVERY {
                    cache_t = 0.0;
                    platform::cache_on_leave(save::AUTOSAVE_KEY, &app.autosave_json());
                }
                if autosave_t >= AUTOSAVE_EVERY {
                    autosave_t = 0.0;
                    platform::storage_set(save::AUTOSAVE_KEY, &app.autosave_json());
                    menu.has_autosave = true;
                }
            }
        }
        let hear = app.cam.zoom * 1.2;
        for ev in app.game.events.drain(..) {
            sounds.play(ev, vec2(app.cam.tx, app.cam.tz), hear, now);
        }
        for m in app.game.msgs.drain(..) {
            ui.log.push((m, now));
        }

        draw_frame(&mut app, &gfx, &mut r3d, &mut ui, &mut menu, &sounds, &inp, now);
        next_frame().await
    }
}

#[allow(clippy::too_many_arguments)]
fn draw_frame(app: &mut App, gfx: &Gfx, r3d: &mut R3d, ui: &mut Ui, menu: &mut Menu, sounds: &SoundBank, inp: &Input, now: f64) {
    let (mx, my) = mouse_position();
    let blocked = menu.open() || ui.show_help || ui.show_langsel;
    let over_ui = blocked || ui.over_ui(mx, my);
    let hover_tile = app.cam.pick_tile(&app.game.map, mx, my).map(|(x, z, _)| (x, z));
    let ground = app.cam.ground_point(mx, my);
    clear_background(Color::from_rgba(4, 3, 5, 255));
    let (color, radius) = match ui.tool {
        Tool::Dig => (Color::new(1.0, 0.85, 0.3, 1.0), None),
        Tool::Hand => (Color::new(0.9, 0.75, 0.6, 1.0), None),
        Tool::Room(_) => (Color::new(0.4, 0.85, 1.0, 1.0), None),
        Tool::Sell => (Color::new(1.0, 0.5, 0.3, 1.0), None),
        Tool::Flag => (Color::new(1.0, 0.3, 0.3, 1.0), None),
        Tool::Lightning => (Color::new(1.0, 1.0, 0.6, 1.0), Some((ground.x, ground.y, 1.6))),
        Tool::Heal => (Color::new(0.4, 1.0, 0.5, 1.0), Some((ground.x, ground.y, 2.55))),
        Tool::Summon => (Color::new(0.8, 0.5, 1.0, 1.0), None),
    };
    let ov = Overlay {
        hover: if over_ui { None } else { hover_tile.filter(|&(x, z)| inb(x, z)) },
        rect: inp.ldown.and_then(|(sx, sy)| hover_tile.map(|(ex, ey)| (sx, sy, ex.clamp(0, MW as i32 - 1), ey.clamp(0, MH as i32 - 1)))),
        color,
        radius: if over_ui { None } else { radius },
        high: ui.tool == Tool::Dig,
    };
    r3d.draw(&app.game, gfx, &app.cam, now, &ov);
    let title_screen = matches!(
        menu.page,
        Some(Page::Title) | Some(Page::Settings { from_title: true, .. }) | Some(Page::KeyCapture { from_title: true, .. })
    );
    if !title_screen {
        let info = if over_ui {
            Vec::new()
        } else {
            let ent = r3d.pick_ent(&app.game, &app.cam, mx, my, false);
            hover_info(&app.game, ent, hover_tile)
        };
        ui.draw(&app.game, gfx, &app.cam, sounds, &app.settings, &info, now);
    } else {
        ui.rects.clear();
    }
    if app.status.as_ref().map_or(false, |(_, t)| now - t > 4.0) {
        app.status = None;
    }
    menu.draw(gfx, &app.settings, app.status.as_ref().map(|(s, _)| s.as_str()));
    if !menu.open() || ui.show_help || ui.show_langsel {
        ui.draw_dialogs(&app.game, gfx);
    }
}