pane_ui 0.1.0

use serde::Deserialize;
use std::sync::mpsc;
use std::time::{Duration, SystemTime};

// ── Internal Message Bus ──────────────────────────────────────────────────────

#[derive(Debug)]
pub(crate) enum UiMsg {
    SwitchRoot(String),
    SwitchTabPage {
        tab_id: String,
        page: usize,
    },
    Quit,
    Custom(String),
    Reload,
    Slider(String, f32),
    TextChanged(String, String),
    TextSubmitted(String, String),
    Toggle(String, bool),
    Dropdown(String, usize, String),
    Radio(String, usize, String),
    /// Internal: spawns a toast widget into the active root. Fired by `PressAction::Toast`.
    Toast {
        message: String,
        duration: f32,
        x: f32,
        y: f32,
        width: f32,
        height: f32,
    },
}

// ── RON Data Structures ───────────────────────────────────────────────────────

#[derive(Deserialize)]
pub struct MenuDef {
    #[serde(default)]
    pub hot_reload: bool,
    #[serde(default)]
    pub headless_accessible: bool,
    #[serde(default)]
    pub shader_dirs: Vec<String>,
    #[serde(default)]
    pub style_dirs: Vec<String>,
    pub background: Option<String>,
    #[serde(default)]
    pub clear_color: Option<crate::draw::Color>,
    pub default_style: Option<String>,
    pub start_root: String,
    pub roots: Vec<RootDef>,
}

#[derive(Deserialize)]
pub struct RootDef {
    pub name: String,
    #[serde(default)]
    pub buttons: Vec<ButtonDef>,
    #[serde(default)]
    pub scroll_lists: Vec<ScrollListDef>,
    #[serde(default)]
    pub bars: Vec<BarDef>,
    #[serde(default)]
    pub popouts: Vec<PopoutDef>,
    #[serde(default)]
    pub toggles: Vec<ToggleDef>,
    #[serde(default)]
    pub sliders: Vec<SliderDef>,
    #[serde(default)]
    pub labels: Vec<FreeLabelDef>,
    #[serde(default)]
    pub dividers: Vec<DividerDef>,
    #[serde(default)]
    pub images: Vec<ImageDef>,
    #[serde(default)]
    pub text_boxes: Vec<TextBoxDef>,
    #[serde(default)]
    pub progress_bars: Vec<ProgressBarDef>,
    #[serde(default)]
    pub scroll_panes: Vec<ScrollPaneDef>,
    #[serde(default)]
    pub dropdowns: Vec<DropdownDef>,
    #[serde(default)]
    pub radio_groups: Vec<RadioGroupDef>,
    #[serde(default)]
    pub actors: Vec<ActorDef>,
    #[serde(default)]
    pub tabs: Vec<TabDef>,
}

#[derive(Deserialize)]
pub struct BarDef {
    pub id: String,
    #[serde(default)]
    pub edge: Option<BarEdgeDef>,
    pub thickness: f32,
    #[serde(default)]
    pub pad: f32,
    #[serde(default)]
    pub gap: f32,
    pub style: Option<String>,
    pub items: Vec<BarItemDef>,
    #[serde(default)]
    pub manual: bool,
    /// X position when `edge` is `None` or `Free` (screen-space, origin at center).
    #[serde(default)]
    pub x: f32,
    /// Y position when `edge` is `None` or `Free`.
    #[serde(default)]
    pub y: f32,
    /// Width override for free-positioned bars. If 0.0, uses `thickness` for vertical bars.
    #[serde(default)]
    pub width: f32,
    /// Height override for free-positioned bars. If 0.0, uses `thickness` for horizontal bars.
    #[serde(default)]
    pub height: f32,
}

#[derive(Deserialize, PartialEq, Eq)]
pub enum BarEdgeDef {
    Top,
    Bottom,
    Left,
    Right,
    Free,
}

#[derive(Deserialize)]
pub struct PopoutDef {
    pub id: String,
    #[serde(default)]
    pub closed_x: f32,
    #[serde(default)]
    pub closed_y: f32,
    #[serde(default)]
    pub open_x: f32,
    #[serde(default)]
    pub open_y: f32,
    pub width: f32,
    pub height: f32,
    pub toggle_id: String,
    pub style: Option<String>,
    pub edge: Option<PopoutEdgeDef>,
    #[serde(default = "default_true")]
    pub shadow: bool,
    #[serde(default)]
    pub horizontal: bool,
    #[serde(default)]
    pub gap: f32,
    #[serde(default)]
    pub full_span: bool,
    #[serde(default)]
    pub home_toggles: bool,
    #[serde(default)]
    pub items: Vec<PopoutItemDef>,
}

const fn default_true() -> bool {
    true
}

#[derive(Deserialize, Clone, Copy)]
pub enum PopoutEdgeDef {
    Left,
    Right,
    Top,
    Bottom,
}

#[derive(Deserialize)]
pub enum PopoutItemDef {
    Button(ButtonDef),
    ScrollList(ScrollListDef),
    Bar(BarDef),
    Popout(PopoutDef),
}

#[derive(Deserialize)]
pub enum BarItemDef {
    Button(ListButtonDef),
    Label(LabelDef),
    Spacer,
    ScrollList(ScrollListDef),
}

#[derive(Deserialize)]
pub struct LabelDef {
    pub id: String,
    pub text: String,
    #[serde(default = "default_label_size")]
    pub size: f32,
    pub color: Option<crate::draw::Color>,
    #[serde(default)]
    pub width: f32,
}

const fn default_label_size() -> f32 {
    24.0
}

#[derive(Deserialize)]
pub struct ButtonDef {
    pub id: String,
    pub x: f32,
    pub y: f32,
    pub width: f32,
    pub height: f32,
    pub text: String,
    pub tooltip: Option<String>,
    pub style: Option<String>,
    pub on_press: PressAction,
    #[serde(default)]
    pub nav_default: bool,
}

#[derive(Deserialize)]
pub struct ScrollListDef {
    pub id: String,
    pub x: f32,
    pub y: f32,
    pub width: f32,
    pub height: f32,
    #[serde(default)]
    pub pad_left: f32,
    #[serde(default)]
    pub pad_right: f32,
    #[serde(default)]
    pub pad_top: f32,
    #[serde(default)]
    pub pad_bottom: f32,
    #[serde(default)]
    pub gap: f32,
    pub style: Option<String>,
    #[serde(default)]
    pub horizontal: bool,
    #[serde(default)]
    pub full_span: bool,
    pub items: Vec<ListButtonDef>,
}

#[derive(Deserialize)]
pub struct ListButtonDef {
    pub id: String,
    pub height: f32,
    /// Width used when the parent [`ScrollListDef`] has `horizontal: true`.
    #[serde(default)]
    pub width: f32,
    pub text: String,
    pub tooltip: Option<String>,
    pub style: Option<String>,
    pub on_press: PressAction,
}

#[derive(Deserialize, Clone)]
pub enum PressAction {
    /// Switch the active root to the named root.
    SwitchRoot(String),
    /// Jump a tab widget to a specific page index.
    SwitchTabPage { tab_id: String, page: usize },
    /// Exit the application.
    Quit,
    /// Print a debug message to stdout when the button is pressed.
    Print(String),
    /// Emit a [`crate::api::PaneAction::Custom`] with the given tag string.
    Custom(String),
    /// Show a transient toast notification. All geometry is in the 1080-unit grid space.
    ///
    /// `duration`, `width`, and `height` are optional and default to `2.0`, `400.0`, and `60.0`.
    /// `x` and `y` default to `0.0` (screen centre).
    Toast {
        /// Text displayed inside the toast.
        message: String,
        /// How long the toast stays visible, in seconds. Defaults to `2.0`.
        #[serde(default = "default_toast_duration")]
        duration: f32,
        /// Horizontal centre of the toast in grid units. Defaults to `0.0`.
        #[serde(default)]
        x: f32,
        /// Vertical centre of the toast in grid units. Defaults to `0.0`.
        #[serde(default)]
        y: f32,
        /// Width of the toast in grid units. Defaults to `400.0`.
        #[serde(default = "default_toast_width")]
        width: f32,
        /// Height of the toast in grid units. Defaults to `60.0`.
        #[serde(default = "default_toast_height")]
        height: f32,
    },
    /// Internal: emitted by radio option buttons. Never appears in RON files.
    RadioSelect { group_id: String, index: usize },
    /// Internal: emitted by dropdown option buttons. Never appears in RON files.
    DropdownSelect { dropdown_id: String, index: usize },
}

const fn default_toast_duration() -> f32 {
    2.0
}
const fn default_toast_width() -> f32 {
    400.0
}
const fn default_toast_height() -> f32 {
    60.0
}

impl PressAction {
    /// True for actions that require post-press root mutation (`RadioSelect`, `DropdownSelect`).
    #[must_use]
    pub const fn is_internal(&self) -> bool {
        matches!(self, Self::RadioSelect { .. } | Self::DropdownSelect { .. })
    }
}

#[derive(Deserialize)]
pub struct ToggleDef {
    pub id: String,
    pub x: f32,
    pub y: f32,
    pub width: f32,
    pub height: f32,
    pub text: String,
    pub tooltip: Option<String>,
    #[serde(default)]
    pub checked: bool,
    pub style_off: String,
    pub style_on: String,
    pub on_change: ToggleAction,
}

#[derive(Deserialize, Clone)]
pub enum ToggleAction {
    Print,
    Custom(String),
}

// ── Load ──────────────────────────────────────────────────────────────────────

/// Parse a RON menu file, returning an error string on failure instead of panicking.
/// Used during hot-reload so a bad edit doesn't crash the running app.
pub(crate) fn load_menu_soft(path: &str) -> Result<MenuDef, String> {
    let src = std::fs::read_to_string(path).map_err(|e| e.to_string())?;
    ron::Options::default()
        .with_default_extension(
            ron::extensions::Extensions::IMPLICIT_SOME
                | ron::extensions::Extensions::UNWRAP_NEWTYPES,
        )
        .from_str(&src)
        .map_err(|e| {
            eprintln!("[pane_ui] Reload parse error: {e}");
            e.to_string()
        })
}

/// Parse a RON menu file, panicking with a clear message on failure.
/// Used at startup where there is no sensible fallback.
pub(crate) fn load_menu(path: &str) -> MenuDef {
    load_menu_soft(path).unwrap_or_else(|e| panic!("[pane_ui] Failed to load '{path}': {e}"))
}

// ── Watcher ───────────────────────────────────────────────────────────────────

/// Spawn a background thread that polls the menu RON file, shader dirs, and style dirs
/// for modification-time changes every second, sending [`UiMsg::Reload`] on any change.
pub(crate) fn spawn_watcher(
    path: String,
    shader_dirs: Vec<String>,
    style_dirs: Vec<String>,
    tx: mpsc::Sender<UiMsg>,
) {
    std::thread::spawn(move || {
        let collect_stamps = || -> Vec<(String, Option<SystemTime>)> {
            let mut stamps = Vec::new();
            stamps.push((
                path.clone(),
                std::fs::metadata(&path).and_then(|m| m.modified()).ok(),
            ));
            for dir in &shader_dirs {
                if let Ok(entries) = std::fs::read_dir(dir) {
                    for entry in entries.filter_map(std::result::Result::ok) {
                        let p = entry.path();
                        if p.extension().is_some_and(|x| x == "wgsl") {
                            stamps.push((
                                p.to_string_lossy().to_string(),
                                std::fs::metadata(&p).and_then(|m| m.modified()).ok(),
                            ));
                        }
                    }
                }
            }
            for dir in &style_dirs {
                if let Ok(entries) = std::fs::read_dir(dir) {
                    for entry in entries.filter_map(std::result::Result::ok) {
                        let p = entry.path();
                        if p.extension().is_some_and(|x| x == "ron") {
                            stamps.push((
                                p.to_string_lossy().to_string(),
                                std::fs::metadata(&p).and_then(|m| m.modified()).ok(),
                            ));
                        }
                    }
                }
            }
            stamps
        };

        let mut last_stamps = collect_stamps();
        loop {
            std::thread::sleep(Duration::from_secs(1));
            let new_stamps = collect_stamps();
            if new_stamps != last_stamps {
                let _ = tx.send(UiMsg::Reload);
            }
            last_stamps = new_stamps;
        }
    });
}

// ── Slider ────────────────────────────────────────────────────────────────────

#[derive(Deserialize)]
pub struct SliderDef {
    pub id: String,
    pub x: f32,
    pub y: f32,
    pub width: f32,
    pub height: f32,
    pub min: f32,
    pub max: f32,
    pub value: f32,
    #[serde(default)]
    pub step: Option<f32>,
    pub tooltip: Option<String>,
    pub style_track: String,
    pub style_thumb: String,
    pub on_change: SliderAction,
}

// ── Static Display Items ──────────────────────────────────────────────────────

#[derive(Deserialize)]
pub struct FreeLabelDef {
    pub id: String,
    pub x: f32,
    pub y: f32,
    pub text: String,
    #[serde(default = "default_label_size")]
    pub size: f32,
    pub color: Option<crate::draw::Color>,
    #[serde(default)]
    pub width: f32,
}

#[derive(Deserialize)]
pub struct DividerDef {
    pub id: String,
    pub x: f32,
    pub y: f32,
    pub width: f32,
    pub height: f32,
    pub style: String,
    #[serde(default)]
    pub full_span: bool,
}

#[derive(Deserialize)]
pub struct ImageDef {
    pub id: String,
    pub x: f32,
    pub y: f32,
    pub width: f32,
    pub height: f32,
    pub path: String,
    #[serde(default)]
    pub gif_mode: Option<crate::textures::GifMode>,
}

#[derive(Deserialize)]
pub struct TextBoxDef {
    pub id: String,
    pub x: f32,
    pub y: f32,
    pub width: f32,
    pub height: f32,
    #[serde(default)]
    pub hint: String,
    #[serde(default)]
    pub max_len: Option<usize>,
    pub tooltip: Option<String>,
    pub style: String,
    #[serde(default)]
    pub style_focus: Option<String>,
    pub on_change: TextBoxAction,
    pub on_submit: TextBoxAction,
    #[serde(default)]
    pub password: bool,
    #[serde(default)]
    pub multiline: bool,
    #[serde(default)]
    pub rows: Option<u32>,
    #[serde(default)]
    pub font_size: Option<f32>,
}

#[derive(Deserialize)]
pub struct ProgressBarDef {
    pub id: String,
    pub x: f32,
    pub y: f32,
    pub width: f32,
    pub height: f32,
    pub value: f32,
    pub style_track: String,
    pub style_fill: String,
}

#[derive(Deserialize, Clone)]
pub enum TextBoxAction {
    Print,
    Custom(String),
    None,
}

#[derive(Deserialize, Clone)]
pub enum SliderAction {
    Print,
    Custom(String),
}

// ── ScrollPane ────────────────────────────────────────────────────────────────

#[derive(Deserialize)]
pub struct ScrollPaneDef {
    pub id: String,
    pub x: f32,
    pub y: f32,
    pub width: f32,
    pub height: f32,
    #[serde(default)]
    pub pad_left: f32,
    #[serde(default)]
    pub pad_right: f32,
    #[serde(default)]
    pub pad_top: f32,
    #[serde(default)]
    pub pad_bottom: f32,
    #[serde(default)]
    pub gap: f32,
    pub style: Option<String>,
    #[serde(default)]
    pub horizontal: bool,
    #[serde(default)]
    pub full_span: bool,
    #[serde(default)]
    pub manual: bool,
    pub items: Vec<ContainerItemDef>,
}

#[derive(Deserialize)]
pub enum ContainerItemDef {
    Button(ButtonDef),
    Toggle(ToggleDef),
    Slider(SliderDef),
    TextBox(TextBoxDef),
    Label(FreeLabelDef),
    Divider(DividerDef),
    Image(ImageDef),
    ProgressBar(ProgressBarDef),
    ScrollPane(ScrollPaneDef),
    ScrollList(ScrollListDef),
    Tab(TabDef),
}

// ── Tab ───────────────────────────────────────────────────────────────────────

#[derive(Deserialize)]
pub struct TabPageDef {
    pub label: String,
    pub items: Vec<ContainerItemDef>,
}

#[derive(Deserialize)]
pub struct TabDef {
    pub id: String,
    pub x: f32,
    pub y: f32,
    pub width: f32,
    pub height: f32,
    #[serde(default)]
    pub pad_left: f32,
    #[serde(default)]
    pub pad_right: f32,
    #[serde(default)]
    pub pad_top: f32,
    #[serde(default)]
    pub pad_bottom: f32,
    #[serde(default)]
    pub gap: f32,
    pub style: Option<String>,
    pub pages: Vec<TabPageDef>,
    #[serde(default)]
    pub full_span: bool,
}

// ── Dropdown ──────────────────────────────────────────────────────────────────

#[derive(Deserialize)]
pub struct DropdownDef {
    pub id: String,
    pub x: f32,
    pub y: f32,
    pub width: f32,
    pub height: f32,
    pub options: Vec<String>,
    #[serde(default)]
    pub selected: usize,
    pub tooltip: Option<String>,
    pub style: Option<String>,
    pub style_list: Option<String>,
    pub style_item: Option<String>,
    pub on_change: DropdownAction,
}

#[derive(Deserialize, Clone)]
pub enum DropdownAction {
    Print,
    Custom(String),
}

// ── Actor ─────────────────────────────────────────────────────────────────────

#[derive(Deserialize)]
pub struct ActorDef {
    pub id: String,
    pub x: f32,
    pub y: f32,
    pub width: f32,
    pub height: f32,
    pub style: Option<String>,
    /// Base gif path — always loops automatically. Optional.
    pub gif: Option<String>,
    #[serde(default)]
    pub z_front: bool,
    #[serde(default = "default_true")]
    pub return_on_end: bool,
    #[serde(default)]
    pub behaviours: Vec<BehaviourDef>,
}

#[derive(Deserialize)]
pub struct BehaviourDef {
    pub trigger: TriggerDef,
    pub action: ActionDef,
}

#[derive(Deserialize, Clone, Copy, PartialEq, Eq)]
pub enum TriggerDef {
    Always,
    OnHoverSelf,
    OnPressSelf,
    OnClickSelf,
    OnClickAnywhere,
}

#[derive(Deserialize, Clone)]
pub enum ActionDef {
    FollowCursor {
        speed: f32,
        #[serde(default)]
        trail: f32,
    },
    MoveTo {
        x: f32,
        y: f32,
        speed: f32,
    },
    /// Swap to a different gif while this trigger is active. Reverts when trigger ends.
    SwapGif {
        path: String,
    },
}

// ── RadioGroup ────────────────────────────────────────────────────────────────

#[derive(Deserialize)]
pub struct RadioGroupDef {
    pub id: String,
    pub x: f32,
    pub y: f32,
    pub width: f32,
    pub height: f32,
    pub options: Vec<String>,
    #[serde(default)]
    pub selected: usize,
    #[serde(default)]
    pub gap: f32,
    pub tooltip: Option<String>,
    pub style_idle: Option<String>,
    pub style_selected: Option<String>,
    pub on_change: RadioAction,
}

#[derive(Deserialize, Clone)]
pub enum RadioAction {
    Print,
    Custom(String),
}