import type { HeatmapColorScheme } from "~/hooks/useAppPreferences.js";

// ─── Heatmap colour palettes ───────────────────────────────────────────────────
// Each palette is [minPct, overlayRgba, barRgba] — overlay is semi-transparent
// (for heatmap mode strips), bar is more opaque (for bar-mode project view).
export const HEATMAP_PALETTES: Record<HeatmapColorScheme, [number, string, string][]> = {
  "green-red": [
    [0,   "rgba(34,197,94,0.18)",   "rgba(34,197,94,0.70)"],
    [25,  "rgba(132,204,22,0.25)",  "rgba(132,204,22,0.75)"],
    [50,  "rgba(250,204,21,0.32)",  "rgba(250,204,21,0.80)"],
    [75,  "rgba(249,115,22,0.40)",  "rgba(249,115,22,0.82)"],
    [90,  "rgba(239,68,68,0.48)",   "rgba(239,68,68,0.85)"],
    [100, "rgba(185,28,28,0.58)",   "rgba(185,28,28,0.88)"],
    [125, "rgba(109,40,217,0.64)",  "rgba(109,40,217,0.88)"],
  ],
  "blue-orange": [
    [0,   "rgba(56,189,248,0.22)",  "rgba(56,189,248,0.70)"],
    [25,  "rgba(59,130,246,0.28)",  "rgba(59,130,246,0.75)"],
    [50,  "rgba(251,191,36,0.35)",  "rgba(251,191,36,0.80)"],
    [75,  "rgba(249,115,22,0.42)",  "rgba(249,115,22,0.82)"],
    [90,  "rgba(239,68,68,0.50)",   "rgba(239,68,68,0.85)"],
    [100, "rgba(185,28,28,0.58)",   "rgba(185,28,28,0.88)"],
    [125, "rgba(109,40,217,0.64)",  "rgba(109,40,217,0.88)"],
  ],
  "purple-yellow": [
    [0,   "rgba(167,139,250,0.22)", "rgba(167,139,250,0.70)"],
    [25,  "rgba(139,92,246,0.28)",  "rgba(139,92,246,0.75)"],
    [50,  "rgba(250,204,21,0.35)",  "rgba(250,204,21,0.80)"],
    [75,  "rgba(245,158,11,0.42)",  "rgba(245,158,11,0.82)"],
    [90,  "rgba(239,68,68,0.50)",   "rgba(239,68,68,0.85)"],
    [100, "rgba(185,28,28,0.58)",   "rgba(185,28,28,0.88)"],
    [125, "rgba(109,40,217,0.64)",  "rgba(109,40,217,0.88)"],
  ],
  "mono": [
    [0,   "rgba(156,163,175,0.18)", "rgba(156,163,175,0.60)"],
    [25,  "rgba(107,114,128,0.25)", "rgba(107,114,128,0.68)"],
    [50,  "rgba(75,85,99,0.30)",    "rgba(75,85,99,0.74)"],
    [75,  "rgba(55,65,81,0.36)",    "rgba(55,65,81,0.80)"],
    [90,  "rgba(31,41,55,0.42)",    "rgba(31,41,55,0.85)"],
    [100, "rgba(17,24,39,0.52)",    "rgba(17,24,39,0.88)"],
    [125, "rgba(0,0,0,0.60)",       "rgba(0,0,0,0.90)"],
  ],
};

// pct = (totalHoursPerDay / 8) * 100. Returns rgba string or null for 0%.
// mode: "overlay" for heatmap strips, "bar" for solid bar fill.
export function heatmapColor(pct: number, scheme: HeatmapColorScheme, mode: "overlay" | "bar" = "overlay"): string | null {
  if (pct <= 0) return null;
  const palette = HEATMAP_PALETTES[scheme] ?? HEATMAP_PALETTES["green-red"];
  let entry = palette[0]!;
  for (const row of palette) {
    if (pct > row[0]) entry = row;
    else break;
  }
  return mode === "bar" ? entry[2] : entry[1];
}

// Legacy alias used by heatmap overlay (overlay mode, green-red default)
export function heatmapBgColor(pct: number, scheme: HeatmapColorScheme = "green-red"): string | null {
  return heatmapColor(pct, scheme, "overlay");
}