/**
 * ResearchIcons — procedural tech glyphs for the tree nodes and the detail
 * readout (128×128 canvas textures, neon stroke + soft glow, transparent
 * background). Names come from each node's `icon` key; unknown names fall
 * back to `diamond`. Tintable at use (Phaser tint multiplies).
 */
import { toColor } from '../utils/Color.js';

export const ICON_NAMES = ['tether', 'tether2', 'anchor', 'signal', 'diamond'];

export function iconKey(name, color = 0x00e5ff) {
  const n = ICON_NAMES.includes(name) ? name : 'diamond';
  const c = toColor(color);
  return `__research_icon_${n}_${c.toString(16).padStart(6, '0')}`;
}

export function ensureIcon(scene, name, color = 0x00e5ff) {
  const key = iconKey(name, color);
  if (scene.textures.exists(key)) return key;

  const S = 128;
  const canvas = document.createElement('canvas');
  canvas.width = S;
  canvas.height = S;
  const ctx = canvas.getContext('2d');
  const hex = `#${toColor(color).toString(16).padStart(6, '0')}`;
  const cx = S / 2;
  const cy = S / 2;

  ctx.clearRect(0, 0, S, S);
  ctx.strokeStyle = hex;
  ctx.fillStyle = hex;
  ctx.shadowColor = hex;
  ctx.shadowBlur = 9;
  ctx.lineWidth = 5;
  ctx.lineCap = 'round';
  ctx.lineJoin = 'round';

  const diamond = (x, y, r) => {
    ctx.beginPath();
    ctx.moveTo(x, y - r);
    ctx.lineTo(x + r, y);
    ctx.lineTo(x, y + r);
    ctx.lineTo(x - r, y);
    ctx.closePath();
    ctx.fill();
  };

  const n = ICON_NAMES.includes(name) ? name : 'diamond';
  if (n === 'tether') {
    // Concentric tether rings + core + tick marks + a satellite on the mid ring.
    const rings = [
      [52, 0.5],
      [38, 0.75],
      [24, 1.0],
    ];
    for (const [r, a] of rings) {
      ctx.globalAlpha = a;
      ctx.beginPath();
      ctx.arc(cx, cy, r, 0, Math.PI * 2);
      ctx.stroke();
    }
    ctx.globalAlpha = 1;
    ctx.beginPath();
    ctx.arc(cx, cy, 7, 0, Math.PI * 2);
    ctx.fill();
    for (const a of [0, Math.PI / 2, Math.PI, (3 * Math.PI) / 2]) {
      ctx.beginPath();
      ctx.moveTo(cx + Math.cos(a) * 55, cy + Math.sin(a) * 55);
      ctx.lineTo(cx + Math.cos(a) * 61, cy + Math.sin(a) * 61);
      ctx.stroke();
    }
    diamond(cx + 38, cy, 8);
  } else if (n === 'tether2') {
    // Level-2 tether: two bright concentric level rings + core + tick
    // marks + TWO satellites riding the outer ring (L1 shows one).
    const rings = [
      [52, 1.0],
      [34, 0.85],
    ];
    for (const [r, a] of rings) {
      ctx.globalAlpha = a;
      ctx.beginPath();
      ctx.arc(cx, cy, r, 0, Math.PI * 2);
      ctx.stroke();
    }
    ctx.globalAlpha = 1;
    ctx.beginPath();
    ctx.arc(cx, cy, 8, 0, Math.PI * 2);
    ctx.fill();
    for (const a of [0, Math.PI / 2, Math.PI, (3 * Math.PI) / 2]) {
      ctx.beginPath();
      ctx.moveTo(cx + Math.cos(a) * 55, cy + Math.sin(a) * 55);
      ctx.lineTo(cx + Math.cos(a) * 61, cy + Math.sin(a) * 61);
      ctx.stroke();
    }
    diamond(cx + 52 * Math.cos(-Math.PI / 3), cy + 52 * Math.sin(-Math.PI / 3), 8);
    diamond(cx + 52 * Math.cos(Math.PI / 3), cy + 52 * Math.sin(Math.PI / 3), 8);
  } else if (n === 'anchor') {
    // Anchor ring + stock + crossbar + flukes (the relay bolted to a body).
    ctx.globalAlpha = 0.9;
    ctx.beginPath();
    ctx.arc(cx, cy, 46, 0, Math.PI * 2);
    ctx.stroke();
    ctx.globalAlpha = 1;
    ctx.beginPath();
    ctx.moveTo(cx, cy - 24);
    ctx.lineTo(cx, cy + 20);
    ctx.stroke();
    ctx.beginPath();
    ctx.arc(cx, cy - 24, 7, 0, Math.PI * 2);
    ctx.stroke();
    ctx.beginPath();
    ctx.moveTo(cx - 15, cy - 8);
    ctx.lineTo(cx + 15, cy - 8);
    ctx.stroke();
    ctx.beginPath();
    ctx.arc(cx, cy + 4, 20, Math.PI * 0.12, Math.PI * 0.88);
    ctx.stroke();
    diamond(cx - 19, cy + 15, 6);
    diamond(cx + 19, cy + 15, 6);
  } else if (n === 'signal') {
    // Long-range array: source dot + rising arcs.
    ctx.beginPath();
    ctx.arc(cx, cy + 22, 7, 0, Math.PI * 2);
    ctx.fill();
    const arcs = [
      [19, 0.95],
      [33, 0.7],
      [47, 0.45],
    ];
    for (const [r, a] of arcs) {
      ctx.globalAlpha = a;
      ctx.beginPath();
      ctx.arc(cx, cy + 22, r, -Math.PI * 0.82, -Math.PI * 0.18);
      ctx.stroke();
    }
    ctx.globalAlpha = 1;
  } else {
    // diamond — the default glyph
    ctx.beginPath();
    ctx.moveTo(cx, cy - 42);
    ctx.lineTo(cx + 42, cy);
    ctx.lineTo(cx, cy + 42);
    ctx.lineTo(cx - 42, cy);
    ctx.closePath();
    ctx.stroke();
    ctx.globalAlpha = 0.55;
    ctx.beginPath();
    ctx.moveTo(cx, cy - 22);
    ctx.lineTo(cx + 22, cy);
    ctx.lineTo(cx, cy + 22);
    ctx.lineTo(cx - 22, cy);
    ctx.closePath();
    ctx.stroke();
    ctx.globalAlpha = 1;
  }

  scene.textures.addCanvas(key, canvas);
  return key;
}