use bevy::prelude::*;

use crate::{loading::TextureAssets, GameState};

pub struct MenuPlugin;

impl Plugin for MenuPlugin {
    fn build(&self, app: &mut App) {
        app.add_systems(OnEnter(GameState::Menu), setup)
            .add_systems(Update, click_button.run_if(in_state(GameState::Menu)))
            .add_systems(OnExit(GameState::Menu), cleanup);
    }
}

#[derive(Component)]
struct ButtonColours {
    normal: Color,
    hovered: Color,
}

impl Default for ButtonColours {
    fn default() -> Self {
        Self {
            normal: Color::srgb(88.0 / 255.0, 91.0 / 255.0, 112.0 / 255.0),
            hovered: Color::srgb(116.0 / 255.0, 199.0 / 255.0, 236.0 / 255.0),
        }
    }
}

#[derive(Component)]
struct Menu;

fn setup(mut commands: Commands, textures: Res<TextureAssets>) {
    commands.spawn((Camera2dBundle::default(), Menu));
    commands
        .spawn((
            NodeBundle {
                style: Style {
                    width: Val::Percent(100.0),
                    height: Val::Percent(100.0),
                    flex_direction: FlexDirection::Column,
                    align_items: AlignItems::Center,
                    justify_content: JustifyContent::Center,
                    ..default()
                },
                ..default()
            },
            Menu,
        ))
        .with_children(|children| {
            let button_colours = ButtonColours::default();
            children
                .spawn((
                    ButtonBundle {
                        style: Style {
                            width: Val::Px(140.0),
                            height: Val::Px(90.0),
                            justify_content: JustifyContent::Center,
                            align_items: AlignItems::Center,
                            ..default()
                        },
                        background_color: button_colours.normal.into(),
                        ..default()
                    },
                    button_colours,
                    ChangeState(GameState::Playing),
                ))
                .with_children(|parent| {
                    parent.spawn(TextBundle::from_section(
                        "Play",
                        TextStyle {
                            font_size: 40.0,
                            color: Color::srgb(205.0 / 255.0, 214.0 / 255.0, 244.0 / 255.0),
                            ..default()
                        },
                    ));
                });
        });
    commands
        .spawn((
            NodeBundle {
                style: Style {
                    flex_direction: FlexDirection::Row,
                    align_items: AlignItems::Center,
                    justify_content: JustifyContent::SpaceAround,
                    bottom: Val::Px(5.),
                    width: Val::Percent(100.),
                    position_type: PositionType::Absolute,
                    ..default()
                },
                ..default()
            },
            Menu,
        ))
        .with_children(|children| {
            children
                .spawn((
                    ButtonBundle {
                        style: Style {
                            width: Val::Px(170.0),
                            height: Val::Px(50.0),
                            justify_content: JustifyContent::SpaceAround,
                            align_items: AlignItems::Center,
                            padding: UiRect::all(Val::Px(5.)),
                            ..Default::default()
                        },
                        background_color: Color::NONE.into(),
                        ..Default::default()
                    },
                    ButtonColours {
                        normal: Color::NONE,
                        ..default()
                    },
                    OpenLink("https://bevyengine.org"),
                ))
                .with_children(|parent| {
                    parent.spawn(TextBundle::from_section(
                        "Made with Bevy",
                        TextStyle {
                            font_size: 15.0,
                            color: Color::srgb(205.0 / 255.0, 214.0 / 255.0, 244.0 / 255.0),
                            ..default()
                        },
                    ));
                    parent.spawn(ImageBundle {
                        image: textures.bevy.clone().into(),
                        style: Style {
                            width: Val::Px(32.),
                            ..default()
                        },
                        ..default()
                    });
                });
            children
                .spawn((
                    ButtonBundle {
                        style: Style {
                            width: Val::Px(170.0),
                            height: Val::Px(50.0),
                            justify_content: JustifyContent::SpaceAround,
                            align_items: AlignItems::Center,
                            padding: UiRect::all(Val::Px(5.)),
                            ..default()
                        },
                        background_color: Color::NONE.into(),
                        ..Default::default()
                    },
                    ButtonColours {
                        normal: Color::NONE,
                        ..default()
                    },
                    OpenLink("https://git.ragarock.moe/silvana/yuno"),
                ))
                .with_children(|parent| {
                    parent.spawn(TextBundle::from_section(
                        "repository",
                        TextStyle {
                            font_size: 15.0,
                            color: Color::srgb(205.0 / 255.0, 214.0 / 255.0, 244.0 / 255.0),
                            ..default()
                        },
                    ));
                    parent.spawn(ImageBundle {
                        image: textures.forgejo.clone().into(),
                        style: Style {
                            width: Val::Px(32.),
                            ..default()
                        },
                        ..default()
                    });
                });
        });
}

#[derive(Component)]
struct ChangeState(GameState);

#[derive(Component)]
struct OpenLink(&'static str);

fn click_button(
    mut next_state: ResMut<NextState<GameState>>,
    mut interaction_query: Query<
        (
            &Interaction,
            &mut BackgroundColor,
            &ButtonColours,
            Option<&ChangeState>,
            Option<&OpenLink>,
        ),
        (Changed<Interaction>, With<Button>),
    >,
) {
    for (interaction, mut colour, button_colours, change_state, open_link) in &mut interaction_query
    {
        match *interaction {
            Interaction::Pressed => {
                if let Some(state) = change_state {
                    next_state.set(state.0.clone());
                } else if let Some(link) = open_link {
                    if let Err(error) = webbrowser::open(link.0) {
                        warn!("failed to open link {error:?}");
                    }
                }
            }
            Interaction::Hovered => {
                *colour = button_colours.hovered.into();
            }
            Interaction::None => {
                *colour = button_colours.normal.into();
            }
        }
    }
}

fn cleanup(mut commands: Commands, menu: Query<Entity, With<Menu>>) {
    for entity in menu.iter() {
        commands.entity(entity).despawn_recursive();
    }
}