import { clampRect, type LayoutRect } from "./layoutProfile.js";
import type { Bitmap } from "./ocrPreprocess.js";

// EXPERIMENTAL, read-only lock-status detection (nice-to-have). Genshin shows a
// padlock at the top-right of the artifact detail card: a bright gold fill when
// locked, a dim outline when not. This estimates that icon region and measures
// the fraction of bright "lock-gold" pixels; above a threshold the piece is
// considered locked.
//
// The crop position and threshold need calibration against a reference 16:9
// screenshot before this is wired into the capture pipeline, so it ships pure and
// unit-tested but unused by main.ts. It never drives any in-game action - it only
// reads state for triage.

export function lockIconCropRect(detailRect: LayoutRect, imageSize: { width: number; height: number }): LayoutRect {
  return clampRect(
    {
      x: Math.round(detailRect.x + detailRect.width * 0.735),
      y: Math.round(detailRect.y + detailRect.height * 0.355),
      width: Math.round(detailRect.width * 0.105),
      height: Math.round(detailRect.height * 0.07),
    },
    imageSize,
  );
}

// A gold/highlighted lock pixel: red high, green mid-high, blue low.
function isLockGold(b: number, g: number, r: number): boolean {
  return r >= 180 && g >= 140 && b <= 120 && r > b + 40 && g > b + 20;
}

export function lockSignalRatio(bitmap: Bitmap): number {
  const { data, width, height } = bitmap;
  const pixels = width * height;
  if (pixels === 0) return 0;
  let gold = 0;
  for (let pixel = 0; pixel < pixels; pixel++) {
    const index = pixel * 4;
    if (isLockGold(data[index], data[index + 1], data[index + 2])) gold++;
  }
  return gold / pixels;
}

export const DEFAULT_LOCK_THRESHOLD = 0.06;

export function isLocked(signalRatio: number, threshold: number = DEFAULT_LOCK_THRESHOLD): boolean {
  return signalRatio >= threshold;
}

export function detectLockState(bitmap: Bitmap, threshold: number = DEFAULT_LOCK_THRESHOLD): boolean {
  return isLocked(lockSignalRatio(bitmap), threshold);
}