import fs from "fs";
import path from "path";
import { spawn } from "child_process";
import color from "picocolors";
import { fileURLToPath } from "url";

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);
const toktx = path.join(__dirname, "..", "..", "bin", "toktx.exe");

// 检查 toktx 是否存在
export function checkToktx() {
  if (!fs.existsSync(toktx)) {
    console.error("❌ 找不到 toktx.exe");
    process.exit(1);
  }
}

// 扫描图片文件
export function scanImages(exts) {
  console.log("🔍 扫描目标文件中...");
  const cwd = process.cwd();
  const images = fs.readdirSync(cwd).filter(f =>
    exts.some(ext => f.toLowerCase().endsWith("." + ext))
  );
  return { images, cwd };
}

// 构建压缩参数
export function buildArgs(input, output, config) {
  const args = ["--t2"];

  if (config.encoding === "uastc") {
    args.push("--encode", "uastc");
    const zcmpLevel = { none: "0", standard: "10", high: "18", extreme: "22" };
    args.push("--zcmp", zcmpLevel[config.quality] || "10");
  } else if (config.encoding === "etc1s") {
    args.push("--encode", "etc1s");
  } else if (config.encoding === "astc") {
    args.push("--encode", "astc");
    const blkSize = { none: "8x8", standard: "6x6", high: "5x5", extreme: "4x4" };
    args.push("--astc_blk_d", blkSize[config.quality] || "6x6");
  }

  if (config.mipmap === "auto") {
    args.push("--genmipmap");
  }

  args.push(output, input);
  return args;
}

// 压缩单个文件
export function compressFile(img, config, cwd, progress) {
  const baseName = img.replace(/\.[^.]+$/, "");
  const out = baseName + ".ktx2";

  // 点动画
  let dots = 0;
  const dotAnim = setInterval(() => {
    const dotStr = ".".repeat(dots);
    process.stdout.write(`\r${progress} ${img} 正在转换中${dotStr}   `);
    dots = dots >= 3 ? 0 : dots + 1;
  }, 300);

  process.stdout.write(`${progress} ${img} 正在转换中.`);

  const args = buildArgs(img, out, config);

  return new Promise((resolve) => {
    const proc = spawn(toktx, args, { cwd });

    let stderr = "";
    proc.stderr?.on("data", data => {
      stderr += data.toString();
    });

    proc.on("close", code => {
      clearInterval(dotAnim);
      if (code === 0) {
        console.log(`\r${progress} ${color.green("✓")} ${out}              `);
        resolve({ success: true });
      } else {
        console.log(`\r${progress} ${color.red("✗")} ${img} 失败          `);
        if (stderr) {
          console.log(color.dim(`   错误: ${stderr.trim()}`));
        }
        resolve({ success: false, error: stderr });
      }
    });

    proc.on("error", err => {
      clearInterval(dotAnim);
      console.log(`\r${progress} ${color.red("✗")} ${img} 失败          `);
      console.log(color.dim(`   错误: ${err.message}`));
      resolve({ success: false, error: err.message });
    });
  });
}

// 批量压缩
export async function compressAll(images, config, cwd) {
  const total = images.length;
  let finished = 0;
  let failed = 0;

  for (const img of images) {
    finished++;
    const progress = `(${finished}/${total})`;
    const result = await compressFile(img, config, cwd, progress);
    if (!result.success) failed++;
  }

  return { total, failed };
}