// OD Figma Import — plugin main thread.
//
// Rebuilds an OD Figma capture IR (produced by the OD Clipper / OD Library; see
// IR.md) into editable Figma layers. The UI (ui.html) hands us a parsed IR
// object; we preload its fonts, then walk the node-tree creating FRAME / TEXT /
// RECTANGLE nodes at their captured geometry with fills, strokes, corner radii
// and shadows.
//
// Standalone, dependency-free, no build step — loaded via
// "Plugins → Development → Import plugin from manifest…".

figma.showUI(__html__, { width: 340, height: 420, title: 'OD Figma Import' });

figma.ui.onmessage = async (msg) => {
  if (!msg) return;
  if (msg.type === 'cancel') {
    figma.closePlugin();
    return;
  }
  if (msg.type === 'import') {
    try {
      const ir = msg.ir;
      if (!ir || !ir.root) throw new Error('Not an OD Figma capture (missing root).');
      const container = await importIr(ir);
      figma.ui.postMessage({ type: 'done', name: container.name });
      figma.notify(`Imported “${container.name}”`);
    } catch (err) {
      figma.ui.postMessage({ type: 'error', message: String((err && err.message) || err) });
    }
  }
};

// --- font preloading -------------------------------------------------------

let LOADED_FONTS = new Set();
const fontKey = (family, style) => `${family} ${style}`;

async function tryLoadFont(family, style) {
  const key = fontKey(family, style);
  if (LOADED_FONTS.has(key)) return true;
  try {
    await figma.loadFontAsync({ family, style });
    LOADED_FONTS.add(key);
    return true;
  } catch {
    return false;
  }
}

async function preloadFonts(fonts) {
  LOADED_FONTS = new Set();
  await tryLoadFont('Inter', 'Regular'); // guaranteed fallback
  for (const f of fonts || []) {
    const family = f && f.family;
    if (!family) continue;
    const styles = (f.styles && f.styles.length ? f.styles : ['Regular']);
    for (const style of styles) await tryLoadFont(family, style);
  }
}

// Resolve a usable, already-loaded font for a text node.
function resolveFont(family, style) {
  if (LOADED_FONTS.has(fontKey(family, style))) return { family, style };
  if (LOADED_FONTS.has(fontKey(family, 'Regular'))) return { family, style: 'Regular' };
  return { family: 'Inter', style: 'Regular' };
}

// --- paint / effect helpers ------------------------------------------------

function solidPaint(fill) {
  if (!fill || !fill.color) return null;
  const c = fill.color;
  return {
    type: 'SOLID',
    color: { r: clamp01(c.r), g: clamp01(c.g), b: clamp01(c.b) },
    opacity: fill.opacity == null ? 1 : clamp01(fill.opacity),
  };
}

function imagePaint(fill) {
  if (!fill || !fill.dataUri) return null;
  try {
    const bytes = decodeDataUri(fill.dataUri);
    if (!bytes) return null;
    const image = figma.createImage(bytes);
    return { type: 'IMAGE', scaleMode: fill.scaleMode || 'FILL', imageHash: image.hash };
  } catch {
    return null;
  }
}

function toPaints(fills) {
  const out = [];
  for (const f of fills || []) {
    const paint = f && f.type === 'IMAGE' ? imagePaint(f) : solidPaint(f);
    if (paint) out.push(paint);
  }
  return out;
}

function toEffects(effects) {
  const out = [];
  for (const e of effects || []) {
    if (!e || e.type !== 'DROP_SHADOW') continue;
    const c = e.color || { r: 0, g: 0, b: 0, a: 0.25 };
    out.push({
      type: 'DROP_SHADOW',
      color: { r: clamp01(c.r), g: clamp01(c.g), b: clamp01(c.b), a: c.a == null ? 0.25 : clamp01(c.a) },
      offset: { x: (e.offset && e.offset.x) || 0, y: (e.offset && e.offset.y) || 0 },
      radius: Math.max(0, e.radius || 0),
      spread: Math.max(0, e.spread || 0),
      visible: true,
      blendMode: 'NORMAL',
    });
  }
  return out;
}

function applyBoxProps(node, spec) {
  const fills = toPaints(spec.fills);
  if ('fills' in node) node.fills = fills;
  if (spec.strokes && 'strokes' in node) {
    const strokes = toPaints(spec.strokes);
    if (strokes.length) {
      node.strokes = strokes;
      if (spec.strokeWeight && 'strokeWeight' in node) node.strokeWeight = spec.strokeWeight;
    }
  }
  if ('cornerRadius' in node && typeof spec.cornerRadius === 'number') {
    node.cornerRadius = spec.cornerRadius;
  }
  if (spec.rectangleCornerRadii && 'topLeftRadius' in node) {
    const r = spec.rectangleCornerRadii;
    node.topLeftRadius = r.topLeft || 0;
    node.topRightRadius = r.topRight || 0;
    node.bottomRightRadius = r.bottomRight || 0;
    node.bottomLeftRadius = r.bottomLeft || 0;
  }
  const effects = toEffects(spec.effects);
  if (effects.length && 'effects' in node) node.effects = effects;
  if (typeof spec.opacity === 'number' && 'opacity' in node) node.opacity = spec.opacity;
}

// --- tree construction -----------------------------------------------------

async function importIr(ir) {
  await preloadFonts(ir.fonts);
  const root = ir.root;
  const container = figma.createFrame();
  container.name = (ir.source && ir.source.title) || 'OD Capture';
  container.clipsContent = true;
  container.resize(Math.max(1, root.width || 1), Math.max(1, root.height || 1));
  applyBoxProps(container, root);
  // White backstop when the page root declared no background.
  if (!container.fills || !container.fills.length) {
    container.fills = [{ type: 'SOLID', color: { r: 1, g: 1, b: 1 } }];
  }
  figma.currentPage.appendChild(container);
  container.x = 0;
  container.y = 0;

  const rootAbsX = root.x || 0;
  const rootAbsY = root.y || 0;
  for (const child of root.children || []) {
    await buildNode(child, container, rootAbsX, rootAbsY);
  }

  figma.currentPage.selection = [container];
  figma.viewport.scrollAndZoomIntoView([container]);
  return container;
}

// Build one IR node under `parent`. `pax/pay` are the parent's absolute
// document coordinates, so child placement converts to parent-relative.
async function buildNode(spec, parent, pax, pay) {
  try {
    if (spec.type === 'TEXT') {
      const t = figma.createText();
      const font = resolveFont(spec.fontFamily || 'Inter', spec.fontStyle || 'Regular');
      t.fontName = font;
      t.characters = spec.characters || '';
      if (spec.fontSize) t.fontSize = Math.max(1, spec.fontSize);
      if (spec.lineHeight) t.lineHeight = { value: spec.lineHeight, unit: 'PIXELS' };
      if (spec.letterSpacing) t.letterSpacing = { value: spec.letterSpacing, unit: 'PIXELS' };
      t.textAlignHorizontal = spec.textAlign || 'LEFT';
      const color = spec.color || { r: 0, g: 0, b: 0 };
      t.fills = [{ type: 'SOLID', color: { r: clamp01(color.r), g: clamp01(color.g), b: clamp01(color.b) },
        opacity: spec.opacity == null ? 1 : clamp01(spec.opacity) }];
      t.textAutoResize = 'NONE';
      safeResize(t, spec.width, spec.height);
      parent.appendChild(t);
      t.x = (spec.x || 0) - pax;
      t.y = (spec.y || 0) - pay;
      return t;
    }

    const hasChildren = Array.isArray(spec.children) && spec.children.length;
    const node = spec.type === 'RECTANGLE' && !hasChildren ? figma.createRectangle() : figma.createFrame();
    node.name = spec.name || spec.type.toLowerCase();
    if (node.type === 'FRAME') {
      node.clipsContent = Boolean(spec.clipsContent);
      node.fills = []; // default frame fill removed; applyBoxProps sets real fills
    }
    safeResize(node, spec.width, spec.height);
    applyBoxProps(node, spec);
    parent.appendChild(node);
    node.x = (spec.x || 0) - pax;
    node.y = (spec.y || 0) - pay;

    if (hasChildren && node.type === 'FRAME') {
      const ax = spec.x || 0;
      const ay = spec.y || 0;
      for (const child of spec.children) await buildNode(child, node, ax, ay);
    }
    return node;
  } catch {
    return null; // one bad node must not abort the whole import
  }
}

// --- low-level helpers -----------------------------------------------------

function clamp01(n) {
  const v = Number(n);
  if (!Number.isFinite(v)) return 0;
  return v < 0 ? 0 : v > 1 ? 1 : v;
}

function safeResize(node, w, h) {
  const width = Math.max(1, Math.round(Number(w) || 1));
  const height = Math.max(1, Math.round(Number(h) || 1));
  try {
    node.resize(width, height);
  } catch {
    // text with empty characters can't resize to <1; ignore
  }
}

// Decode a `data:<mime>;base64,<payload>` URI into a Uint8Array. We decode
// base64 by hand so we don't depend on atob / figma.base64Decode availability.
const B64 = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';
function decodeDataUri(dataUri) {
  const comma = dataUri.indexOf(',');
  if (comma === -1) return null;
  const meta = dataUri.slice(0, comma);
  let payload = dataUri.slice(comma + 1);
  if (!/;base64/i.test(meta)) {
    // percent-encoded text payload
    const decoded = decodeURIComponent(payload);
    const bytes = new Uint8Array(decoded.length);
    for (let i = 0; i < decoded.length; i++) bytes[i] = decoded.charCodeAt(i) & 0xff;
    return bytes;
  }
  payload = payload.replace(/[^A-Za-z0-9+/=]/g, '');
  const lookup = new Int16Array(256).fill(-1);
  for (let i = 0; i < B64.length; i++) lookup[B64.charCodeAt(i)] = i;
  const len = payload.length;
  const padding = payload.endsWith('==') ? 2 : payload.endsWith('=') ? 1 : 0;
  const outLen = Math.floor((len * 3) / 4) - padding;
  const out = new Uint8Array(outLen);
  let p = 0;
  for (let i = 0; i < len; i += 4) {
    const a = lookup[payload.charCodeAt(i)];
    const b = lookup[payload.charCodeAt(i + 1)];
    const c = lookup[payload.charCodeAt(i + 2)];
    const d = lookup[payload.charCodeAt(i + 3)];
    const chunk = (a << 18) | (b << 12) | ((c & 63) << 6) | (d & 63);
    if (p < outLen) out[p++] = (chunk >> 16) & 0xff;
    if (p < outLen) out[p++] = (chunk >> 8) & 0xff;
    if (p < outLen) out[p++] = chunk & 0xff;
  }
  return out;
}