import * as esbuild from "esbuild";
import { cpSync, mkdirSync, existsSync } from "fs";
import { join, dirname } from "path";
import { fileURLToPath } from "url";

const __dirname = dirname(fileURLToPath(import.meta.url));

const isWatch = process.argv.includes("--watch");
const targetBrowser = process.argv.find((a) => a.startsWith("--browser="))?.split("=")[1] || "all";

const browsers = targetBrowser === "all"
  ? ["chrome", "firefox", "edge", "safari"]
  : [targetBrowser];

// Browser-specific esbuild targets
const browserTargets = {
  chrome: "chrome120",
  edge: "chrome120",  // Edge is Chromium-based
  firefox: "firefox109",
  safari: "safari16",
};

const sharedBuildOptions = {
  entryPoints: [
    "src/background/service-worker.ts",
    "src/popup/popup.ts",
    "src/options/options.ts",
  ],
  bundle: true,
  format: "esm",
  sourcemap: true,
  minify: !isWatch,
  // Force CJS resolution for libsodium (ESM entry has broken sibling import)
  alias: {
    "libsodium-wrappers-sumo":
      "./node_modules/libsodium-wrappers-sumo/dist/modules-sumo/libsodium-wrappers.js",
  },
};

/**
 * Copy static assets (HTML, icons, manifest) to a browser-specific build directory.
 */
function copyStaticAssets(browser) {
  const outDir = join(__dirname, "build", browser);
  mkdirSync(outDir, { recursive: true });

  // Copy manifest
  const manifestSrc = join(__dirname, "manifests", `${browser}.json`);
  if (existsSync(manifestSrc)) {
    cpSync(manifestSrc, join(outDir, "manifest.json"));
  }

  // Copy src (HTML, icons)
  const srcDir = join(__dirname, "src");
  cpSync(srcDir, join(outDir, "src"), { recursive: true, filter: (src) => !src.endsWith(".ts") });
}

async function buildBrowser(browser) {
  const outDir = join("build", browser, "dist");

  const options = {
    ...sharedBuildOptions,
    outdir: outDir,
    target: browserTargets[browser] || "es2020",
  };

  if (isWatch && browsers.length === 1) {
    const ctx = await esbuild.context(options);
    await ctx.watch();
    console.log(`Watching for changes (${browser})...`);
  } else {
    await esbuild.build(options);
  }

  copyStaticAssets(browser);
  console.log(`Build complete: ${browser} → build/${browser}/`);
}

// Also build the default dist/ for backwards compatibility (Chrome)
async function buildDefault() {
  const options = {
    ...sharedBuildOptions,
    outdir: "dist",
    target: "chrome120",
  };

  if (isWatch) {
    const ctx = await esbuild.context(options);
    await ctx.watch();
    console.log("Watching for changes (default)...");
  } else {
    await esbuild.build(options);
    console.log("Build complete (default dist/).");
  }
}

// Build all targets
await buildDefault();
for (const browser of browsers) {
  await buildBrowser(browser);
}