inkferro-core 0.1.0

//! Node data structures mirroring ink's DOM types (dom.ts:8-93).

/// The four element kinds from ink's `ElementNames` (dom.ts:18-23).
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum Kind {
    /// `ink-root`
    Root,
    /// `ink-box`
    Box,
    /// `ink-text`
    Text,
    /// `ink-virtual-text`
    VirtualText,
}

// ─── Style types ─────────────────────────────────────────────────────────────

/// A length/percentage/auto dimension (mirrors Yoga's percent vs. point APIs).
///
/// Used for width, height, min/max, flex-basis, and inset properties.
/// Percentage is stored as 0–100 (ink JS convention); the taffy mapping
/// divides by 100 to obtain 0.0–1.0.
#[derive(Debug, Clone, PartialEq, Default)]
pub enum Dim {
    /// A fixed size in terminal cells.
    Points(f32),
    /// A percentage (0–100) of the parent's corresponding dimension.
    Percent(f32),
    /// Automatic sizing (yoga/taffy default).
    #[default]
    Auto,
}

/// A length or percentage (no auto) used for margin/padding/border/gap.
///
/// Mirrors yoga's numeric-only API for these properties.
#[derive(Debug, Clone, PartialEq)]
pub enum Lp {
    /// A fixed size in terminal cells.
    Points(f32),
    /// A percentage (0–100) of the relevant parent dimension.
    Percent(f32),
}

/// `flexDirection` (styles.ts:504–525).
#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
pub enum FlexDir {
    #[default]
    Row,
    Column,
    RowReverse,
    ColumnReverse,
}

/// `flexWrap` (styles.ts:527–540).
#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
pub enum FlexWrap {
    #[default]
    NoWrap,
    Wrap,
    WrapReverse,
}

/// `alignItems` / `alignSelf` (styles.ts:552–593).
///
/// Used for both `align_items` (`Option<AlignItems>` in taffy) and
/// `align_self` (`Option<AlignSelf>` in taffy).  Taffy has no explicit
/// `Auto` variant for `AlignSelf`; `None` in the `Option` encodes auto.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum Align {
    Stretch,
    FlexStart,
    Center,
    FlexEnd,
    Baseline,
}

/// `alignContent` / `justifyContent` (styles.ts:595–661).
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum ContentAlign {
    FlexStart,
    Center,
    FlexEnd,
    SpaceBetween,
    SpaceAround,
    SpaceEvenly,
    Stretch,
}

/// `display` (styles.ts:721–727).
#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
pub enum Display {
    #[default]
    Flex,
    None,
}

/// `borderStyle` — mirrors `keyof Boxes | BoxStyle` from cli-boxes (styles.ts:255 —
/// type declaration; the `typeof borderStyle === 'string' ? cliBoxes[...] : borderStyle`
/// ternary lives in render-border.ts:32-34).
///
/// Presence (`Some`) means border is active (layout width = 1 per edge); `None`
/// means no border (width = 0).  The renderer uses the variant to select the
/// correct box-drawing characters.
///
/// * `Named` — one of cli-boxes's named styles ("single", "double", "round", …).
/// * `Custom` — caller-supplied box-drawing characters matching `BoxStyle` from
///   cli-boxes.  Eight fields: four corners + four edges.
#[derive(Debug, Clone, PartialEq)]
pub enum BorderStyle {
    /// A named style from cli-boxes (e.g. `"single"`, `"double"`, `"round"`).
    Named(String),
    /// A fully custom `BoxStyle` object supplied directly by the caller
    /// (styles.ts:255 — type declaration; ternary in render-border.ts:32-34).
    Custom {
        top_left: String,
        top: String,
        top_right: String,
        right: String,
        bottom_right: String,
        bottom: String,
        bottom_left: String,
        left: String,
    },
}

/// `position` (styles.ts:415–442).
///
/// Yoga has three values: `absolute`, `relative`, and `static`.
/// Taffy only has `Relative` and `Absolute` — `static` maps to `Relative`
/// (divergence documented in `style_to_taffy`).
#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
pub enum Position {
    #[default]
    Relative,
    Absolute,
    /// Yoga-only; taffy backend maps to `Relative`. The difference is visible
    /// only when inset (top/right/bottom/left) is set on a static node: yoga
    /// ignores inset for static (styles.ts:21), but this mapping honors it.
    /// Accepted: ink's API documents static as ignoring offsets (styles.ts:21)
    /// and Box never defaults to static.
    Static,
}

/// `textWrap` (styles.ts:10-16) — controls text wrapping within an ink-text
/// node.  Lives on `Style` (not a node attribute) because `dom.ts:242` reads
/// it as `node.style?.textWrap`; `wrap-text.ts:3` types it `Styles['textWrap']`.
///
/// Default (when `None`) is `Wrap`, matching ink's `node.style?.textWrap ?? 'wrap'`
/// (dom.ts:242).
#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
pub enum TextWrap {
    /// `'wrap'` — soft word-wrap with hard=true, trim=false (wrap-text.ts:21-25).
    #[default]
    Wrap,
    /// `'hard'` — character-level hard wrap, word_wrap=false (wrap-text.ts:27-32).
    Hard,
    /// `'truncate'` or `'truncate-end'` — truncate at end (wrap-text.ts:33-47).
    TruncateEnd,
    /// `'truncate-middle'` — truncate in the middle.
    TruncateMiddle,
    /// `'truncate-start'` — truncate at the start.
    TruncateStart,
}

/// `overflow` per-axis (styles.ts; Box.tsx resolves the `overflow` shorthand
/// to `overflowX`/`overflowY` before reaching the DOM — styles.ts:731–734).
///
/// Only `overflowX` and `overflowY` are stored here; the `overflow` shorthand
/// is resolved JS-side in Box.tsx (Box.tsx:90-92) and never reaches Rust.
///
/// styles.ts defines overflow as `'visible' | 'hidden'` only (styles.ts:384/391/398).
#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
pub enum Overflow {
    #[default]
    Visible,
    Hidden,
}

/// The layout style for a DOM node.
///
/// Mirrors ink's `Styles` type (styles.ts) with every prop that ink's
/// `apply*` functions write to yoga (styles.ts:415–777).  Layout-inert
/// props (text color, background, border colors) are carried as raw strings
/// for the renderer (M1-5) without influencing the taffy layout pass.
///
/// ### Shorthand resolution
/// * `overflow` shorthand: resolved JS-side in Box.tsx before `setStyle` —
///   only `overflow_x`/`overflow_y` per-axis values reach Rust.
/// * `margin`/`marginX`/`marginY`, `padding`/`paddingX`/`paddingY`, `gap`
///   shorthands: NOT resolved JS-side (yoga handles via `EDGE_ALL` /
///   `GUTTER_ALL`).  Rust carries these shorthands; the taffy mapping
///   collapses them with an `Option::or` cascade.
#[derive(Debug, Clone, PartialEq, Default)]
pub struct Style {
    // ── Position (styles.ts:415–442) ──────────────────────────────────────
    pub position: Option<Position>,
    pub top: Option<Dim>,
    pub right: Option<Dim>,
    pub bottom: Option<Dim>,
    pub left: Option<Dim>,

    // ── Margin (styles.ts:444–472) ────────────────────────────────────────
    /// Shorthand — applies to all four edges (yoga `EDGE_ALL`).
    pub margin: Option<Lp>,
    /// Horizontal shorthand — left + right (yoga `EDGE_HORIZONTAL`).
    pub margin_x: Option<Lp>,
    /// Vertical shorthand — top + bottom (yoga `EDGE_VERTICAL`).
    pub margin_y: Option<Lp>,
    pub margin_top: Option<Lp>,
    pub margin_right: Option<Lp>,
    pub margin_bottom: Option<Lp>,
    pub margin_left: Option<Lp>,

    // ── Padding (styles.ts:474–502) ───────────────────────────────────────
    /// Shorthand — applies to all four edges.
    pub padding: Option<Lp>,
    /// Horizontal shorthand — left + right.
    pub padding_x: Option<Lp>,
    /// Vertical shorthand — top + bottom.
    pub padding_y: Option<Lp>,
    pub padding_top: Option<Lp>,
    pub padding_right: Option<Lp>,
    pub padding_bottom: Option<Lp>,
    pub padding_left: Option<Lp>,

    // ── Flex (styles.ts:504–661) ──────────────────────────────────────────
    pub flex_direction: Option<FlexDir>,
    pub flex_wrap: Option<FlexWrap>,
    pub flex_grow: Option<f32>,
    pub flex_shrink: Option<f32>,
    /// `flexBasis` — yoga accepts number (points), percent string, or auto.
    pub flex_basis: Option<Dim>,
    pub align_items: Option<Align>,
    /// `None` encodes `auto` (taffy has no explicit `AlignSelf::Auto` variant).
    pub align_self: Option<Align>,
    pub align_content: Option<ContentAlign>,
    pub justify_content: Option<ContentAlign>,

    // ── Dimensions (styles.ts:663–719) ────────────────────────────────────
    pub width: Option<Dim>,
    pub height: Option<Dim>,
    pub min_width: Option<Dim>,
    pub min_height: Option<Dim>,
    pub max_width: Option<Dim>,
    pub max_height: Option<Dim>,
    pub aspect_ratio: Option<f32>,

    // ── Display (styles.ts:721–727) ───────────────────────────────────────
    pub display: Option<Display>,

    // ── Border (styles.ts:729–763) ────────────────────────────────────────
    /// `borderStyle` value (styles.ts:255, 745).  `Some(_)` → border active,
    /// layout width = 1 per enabled edge.  `None` → no border (width = 0).
    /// Renderer uses the variant to select box-drawing characters (M1-5).
    pub border_style: Option<BorderStyle>,
    /// `borderTop === false` disables the top border edge (styles.ts:748-749).
    pub border_top: Option<bool>,
    pub border_right: Option<bool>,
    pub border_bottom: Option<bool>,
    pub border_left: Option<bool>,

    // ── Gap (styles.ts:765–777) ───────────────────────────────────────────
    /// All-axes shorthand (yoga `GUTTER_ALL`).
    pub gap: Option<f32>,
    pub column_gap: Option<f32>,
    pub row_gap: Option<f32>,

    // ── Text wrap (styles.ts:10-16; dom.ts:242 reads `node.style?.textWrap`) ──
    /// `textWrap` mode for `ink-text` nodes.  `None` → default `Wrap`
    /// (matches ink's `?? 'wrap'` fallback at dom.ts:242).
    pub text_wrap: Option<TextWrap>,

    // ── Overflow per-axis (Box.tsx:90-92 resolves the shorthand JS-side) ──
    pub overflow_x: Option<Overflow>,
    pub overflow_y: Option<Overflow>,

    // ── Layout-inert visual props (carried for M1-5 renderer) ─────────────
    pub background_color: Option<String>,
    pub border_color: Option<String>,
    pub border_top_color: Option<String>,
    pub border_right_color: Option<String>,
    pub border_bottom_color: Option<String>,
    pub border_left_color: Option<String>,
    pub border_background_color: Option<String>,
    pub border_top_background_color: Option<String>,
    pub border_right_background_color: Option<String>,
    pub border_bottom_background_color: Option<String>,
    pub border_left_background_color: Option<String>,

    // ── Per-edge border dim flags (BOOLEAN) — ink reads these from
    // `node.style.border{Edge}DimColor`; render-border.ts:54-64 resolves
    // border{Edge}DimColor ?? borderDimColor and threads `dim` through stylePiece.
    pub border_dim_color: Option<bool>,
    pub border_top_dim_color: Option<bool>,
    pub border_right_dim_color: Option<bool>,
    pub border_bottom_dim_color: Option<bool>,
    pub border_left_dim_color: Option<bool>,
}

impl Style {
    /// Per-edge border widths `[top, right, bottom, left]` in cells.
    ///
    /// Single source for BOTH the taffy layout reservation and the
    /// render clip inset — these two must never disagree.
    ///
    /// Returns 1 for each edge that is active (border_style is `Some` and
    /// the edge flag is not explicitly `false`), 0 otherwise.
    pub(crate) fn border_edges(&self) -> [u16; 4] {
        let on = self.border_style.is_some();
        let edge = |f: Option<bool>| if on && f != Some(false) { 1u16 } else { 0u16 };
        [
            edge(self.border_top),
            edge(self.border_right),
            edge(self.border_bottom),
            edge(self.border_left),
        ]
    }
}

/// Inline text styling for an `ink-text` subtree (P5.1 SET_TEXT_STYLE).  Mirrors
/// ink's `<Text>` styling props (color, backgroundColor, bold, italic, underline,
/// strikethrough, inverse, dimColor).
///
/// The render walk reads this via `resolve_transform` (render/walk.rs) to compose
/// SGR natively instead of dispatching a per-line JS transform.  Stored alongside
/// `has_transform`; a node carries exactly one of the two.  A styled→plain
/// rerender clears it via `ClearTextStyle` (P6.2 CLEAR_TEXT_STYLE).
#[derive(Debug, Default, Clone, PartialEq)]
pub struct TextStyle {
    pub color: Option<String>,
    pub background_color: Option<String>,
    pub bold: bool,
    pub italic: bool,
    pub underline: bool,
    pub strikethrough: bool,
    pub inverse: bool,
    pub dim_color: bool,
}

// ─── Node ────────────────────────────────────────────────────────────────────

/// Attribute value enum mirroring `DOMNodeAttribute` (dom.ts:93).
///
/// JS `DOMNodeAttribute = boolean | string | number`; the number variant
/// uses `f64` to match JS numeric semantics.
#[derive(Debug, Clone, PartialEq)]
pub enum AttrValue {
    Bool(bool),
    Str(String),
    Number(f64),
}

/// A single node in the arena.
///
/// Mirrors the union of `DOMElement` + `TextNode` from dom.ts (dom.ts:27-81).
/// Fields common to both are always present; `text` is meaningful only on
/// `Text` and `VirtualText` kinds (where ink stores it in a child `#text`
/// node — folded here per task spec).
#[derive(Debug, Clone)]
pub struct Node {
    pub kind: Kind,
    pub parent: Option<u32>,
    pub children: Vec<u32>,
    /// Text content.  Mirrors `TextNode.nodeValue` (dom.ts:79-81).
    /// For `Text`/`VirtualText` nodes.  No-op field on `Root`/`Box`.
    pub text: Option<String>,
    /// Layout and visual style for this node.
    pub style: Style,
    /// String/bool/number attributes — mirrors `DOMElement.attributes`
    /// (dom.ts:29).  Does NOT include `internal_transform` or
    /// `internal_static`; those are separate flags per the reconciler
    /// (reconciler.ts:231-245).
    pub attributes: Vec<(String, AttrValue)>,
    /// `internal_static` flag (reconciler.ts:237-244).
    pub is_static: bool,
    /// Set by `Hide`/`Unhide` ops.  The actual yoga display effect is JS-side.
    pub is_hidden: bool,
    /// `internal_transform` presence flag (reconciler.ts:231-235).
    /// The transform function itself stays JS-side per the FFI design.
    pub has_transform: bool,
    /// Inline text styling (P5.1 SET_TEXT_STYLE).  Read by the render walk via
    /// `resolve_transform` to compose SGR natively.  `None` until a `SetTextStyle`
    /// op writes it; reset to `None` by `ClearTextStyle` on a styled→plain
    /// rerender (P6.2).
    pub text_styling: Option<TextStyle>,
}

impl Node {
    pub fn new(kind: Kind) -> Self {
        Self {
            kind,
            parent: None,
            children: Vec::new(),
            text: None,
            style: Style::default(),
            attributes: Vec::new(),
            is_static: false,
            is_hidden: false,
            has_transform: false,
            text_styling: None,
        }
    }
}