use crate::features::hud::components::{SettingsTimerInput, TimerType};
use crate::features::phase::components::TimerSettings;
use crate::features::savegame::ui::spawn_load_popup;
use crate::prelude::*;
use components::*;
use ui::settings::open_settings_menu;

pub mod components;
pub mod ui;

/// Plugin for the main menu screen.
pub struct StartScreenPlugin;

impl Plugin for StartScreenPlugin {
    fn build(&self, app: &mut App) {
        app.init_resource::<StartScreenTimerSettings>();
        app.add_systems(OnEnter(AppState::StartScreen), setup);
        app.add_systems(OnExit(AppState::StartScreen), cleanup);
        app.add_systems(
            Update,
            (menu, handle_settings_buttons, update_timer_settings_display)
                .run_if(in_state(AppState::StartScreen)),
        );
        app.add_systems(
            PostUpdate,
            apply_start_screen_settings.run_if(in_state(AppState::GameScreen)),
        );
    }
}

/// Spawns the main menu UI.
fn setup(mut commands: Commands) {
    commands.spawn((
        RootMarker::MainMenu,
        Node {
            width: percent(100),
            height: percent(100),
            flex_direction: FlexDirection::Column,
            row_gap: px(10),
            ..Node::center()
        },
        children![
            text("Pomomon Garden", 64.0, Color::WHITE),
            button(
                ButtonType::LoadGame,
                ButtonVariant::Primary,
                Node {
                    width: px(280),
                    padding: UiRect::all(px(10)),
                    ..default()
                },
                |color| text("Spiel laden", 33.0, color)
            ),
            button(
                ButtonType::NewGame,
                ButtonVariant::Primary,
                Node {
                    width: px(280),
                    padding: UiRect::all(px(10)),
                    ..default()
                },
                |color| text("Neues Spiel", 33.0, color)
            ),
            button(
                ButtonType::Settings,
                ButtonVariant::Secondary,
                Node {
                    width: px(280),
                    padding: UiRect::all(px(10)),
                    ..default()
                },
                |color| text("Einstellungen", 33.0, color)
            ),
        ],
    ));
}

/// Handles main menu button interactions.
fn menu(
    mut commands: Commands,
    mut next_state: ResMut<NextState<AppState>>,
    mut interaction_query: Query<(&Interaction, &ButtonType), (Changed<Interaction>, With<Button>)>,
    asset_server: Res<AssetServer>,
) {
    for (interaction, button_type) in &mut interaction_query {
        match *interaction {
            Interaction::Pressed => match button_type {
                ButtonType::LoadGame => {
                    spawn_load_popup(&mut commands, &asset_server);
                }
                ButtonType::NewGame => {
                    commands.insert_resource(SavegamePath::next());
                    next_state.set(AppState::GameScreen);
                }
                ButtonType::Settings => {
                    open_settings_menu(&mut commands);
                }
            },
            _ => (),
        }
    }
}

/// Cleans up main menu resources.
fn cleanup(mut commands: Commands, query: Query<Entity, With<RootMarker>>) {
    for entity in query.iter() {
        commands.entity(entity).despawn();
    }
}

/// Handles button interactions within the settings menu.
fn handle_settings_buttons(
    mut interaction_query: Query<
        (&Interaction, &crate::features::hud::components::ButtonType),
        (Changed<Interaction>, With<Button>),
    >,
    mut timer_settings: ResMut<TimerSettings>,
    mut ss_timer_settings: ResMut<StartScreenTimerSettings>,
    keys: Res<ButtonInput<KeyCode>>,
) {
    let shift_multiplier = if keys.any_pressed([KeyCode::ShiftLeft, KeyCode::ShiftRight]) {
        10
    } else {
        1
    };

    for (interaction, button_type) in &mut interaction_query {
        if *interaction == Interaction::Pressed {
            if let crate::features::hud::components::ButtonType::SettingsTimerChange {
                input,
                amount,
            } = button_type
            {
                match input {
                    SettingsTimerInput::Minutes(timer_type) => {
                        timer_settings.change(timer_type, 60 * amount * shift_multiplier)
                    }
                    SettingsTimerInput::Seconds(timer_type) => {
                        timer_settings.change(timer_type, *amount * shift_multiplier)
                    }
                }
                ss_timer_settings.0 = Some(timer_settings.clone());
            }
        }
    }
}

/// Updates the timer settings display in the settings menu.
fn update_timer_settings_display(
    timer_settings: Res<TimerSettings>,
    mut query: Query<(&SettingsTimerInput, &mut Text)>,
) {
    for (input_type, mut text) in query.iter_mut() {
        match input_type {
            SettingsTimerInput::Minutes(timer_type) => {
                let value = match timer_type {
                    TimerType::Focus => timer_settings.focus_duration,
                    TimerType::ShortBreak => timer_settings.short_break_duration,
                    TimerType::LongBreak => timer_settings.long_break_duration,
                } as f32;

                text.0 = format!("{:0>2}", (value / 60.0).floor());
            }
            SettingsTimerInput::Seconds(timer_type) => {
                let value = match timer_type {
                    TimerType::Focus => timer_settings.focus_duration,
                    TimerType::ShortBreak => timer_settings.short_break_duration,
                    TimerType::LongBreak => timer_settings.long_break_duration,
                };

                text.0 = format!("{:0>2}", (value % 60));
            }
        }
    }
}

/// Applies the timer settings from the start screen once the game screen is entered.
fn apply_start_screen_settings(
    mut settings: ResMut<TimerSettings>,
    mut ss_settings: ResMut<StartScreenTimerSettings>,
) {
    if let Some(new_settings) = ss_settings.0.take() {
        *settings = new_settings;
    }
}