const fs = require("fs");
const path = require("path");

const EXECUTABLE_NAME = "Paseo";
const WRAPPER_MODE = 0o755;
const WRAPPER_SCRIPT = `#!/bin/bash
exec "$(dirname "$(readlink -f "$0")")/${EXECUTABLE_NAME}.bin" --no-sandbox "$@"
`;

// electron-builder arch enum → Node.js arch string
const ARCH_MAP = { 0: "ia32", 1: "x64", 2: "armv7l", 3: "arm64", 4: "universal" };

const RIPGREP_PLATFORM_DIR = {
  darwin: { arm64: "arm64-darwin", x64: "x64-darwin" },
  linux: { arm64: "arm64-linux", x64: "x64-linux" },
  win32: { arm64: "arm64-win32", x64: "x64-win32" },
};

function rmSafe(target) {
  fs.rmSync(target, { recursive: true, force: true });
}

function pruneChildrenExcept(parent, keep) {
  if (!fs.existsSync(parent)) return;
  for (const entry of fs.readdirSync(parent)) {
    if (!keep.has(entry)) {
      rmSafe(path.join(parent, entry));
    }
  }
}

function pruneOnnxRuntime(nodeModules, platform, arch) {
  const onnxBin = path.join(nodeModules, "onnxruntime-node", "bin", "napi-v6");
  if (!fs.existsSync(onnxBin)) return;

  const otherPlatforms = ["darwin", "linux", "win32"].filter((p) => p !== platform);
  for (const p of otherPlatforms) {
    rmSafe(path.join(onnxBin, p));
  }

  pruneChildrenExcept(path.join(onnxBin, platform), new Set([arch]));

  if (platform === "linux") {
    const archDir = path.join(onnxBin, "linux", arch);
    if (fs.existsSync(archDir)) {
      for (const name of fs.readdirSync(archDir)) {
        if (name.includes("cuda") || name.includes("tensorrt")) {
          fs.rmSync(path.join(archDir, name), { force: true });
        }
      }
    }
  }
}

function pruneClaudeAgentSdk(nodeModules, platform, arch) {
  const vendorRoot = path.join(nodeModules, "@anthropic-ai", "claude-agent-sdk", "vendor");
  const keepName = RIPGREP_PLATFORM_DIR[platform]?.[arch];
  if (!keepName) return;

  pruneChildrenExcept(path.join(vendorRoot, "ripgrep"), new Set(["COPYING", keepName]));
  pruneChildrenExcept(path.join(vendorRoot, "tree-sitter-bash"), new Set([keepName]));
}

function pruneNodePty(nodeModules, platform, arch) {
  const prebuilds = path.join(nodeModules, "node-pty", "prebuilds");
  pruneChildrenExcept(prebuilds, new Set([`${platform}-${arch}`]));

  if (platform !== "win32") {
    rmSafe(path.join(nodeModules, "node-pty", "third_party"));
  }
}

function pruneSharpLibvips(nodeModules, platform, arch) {
  const prefix = `sharp-libvips-${platform}-${arch}`;
  const imgDir = path.join(nodeModules, "@img");
  if (!fs.existsSync(imgDir)) return;

  for (const entry of fs.readdirSync(imgDir)) {
    if (entry.startsWith("sharp-") && entry !== prefix && !entry.startsWith(`sharp-${platform}-${arch}`)) {
      rmSafe(path.join(imgDir, entry));
    }
  }
}

function pruneNativeModules(appOutDir, platform, arch) {
  const resourcesDir =
    platform === "darwin"
      ? path.join(appOutDir, `${EXECUTABLE_NAME}.app`, "Contents", "Resources")
      : path.join(appOutDir, "resources");

  const nodeModules = path.join(resourcesDir, "app.asar.unpacked", "node_modules");
  if (!fs.existsSync(nodeModules)) return;

  const before = dirSizeSync(nodeModules);

  pruneOnnxRuntime(nodeModules, platform, arch);
  pruneClaudeAgentSdk(nodeModules, platform, arch);
  pruneNodePty(nodeModules, platform, arch);
  pruneSharpLibvips(nodeModules, platform, arch);

  const after = dirSizeSync(nodeModules);
  const savedMB = ((before - after) / 1024 / 1024).toFixed(1);
  console.log(`Pruned native modules: ${savedMB} MB removed (${fmtMB(before)} → ${fmtMB(after)})`);
}

function dirSizeSync(dir) {
  let total = 0;
  for (const entry of fs.readdirSync(dir, { withFileTypes: true, recursive: true })) {
    if (entry.isFile()) {
      try {
        total += fs.statSync(path.join(entry.parentPath || entry.path, entry.name)).size;
      } catch {}
    }
  }
  return total;
}

function fmtMB(bytes) {
  return `${(bytes / 1024 / 1024).toFixed(1)} MB`;
}

exports.default = async function afterPack(context) {
  const platform = context.electronPlatformName;
  const arch = ARCH_MAP[context.arch] || process.arch;

  pruneNativeModules(context.appOutDir, platform, arch);

  if (platform !== "linux") return;

  const chromeSandbox = path.join(context.appOutDir, "chrome-sandbox");
  if (fs.existsSync(chromeSandbox)) {
    fs.unlinkSync(chromeSandbox);
    console.log("Removed chrome-sandbox from Linux build");
  }

  const executablePath = path.join(context.appOutDir, EXECUTABLE_NAME);
  const wrappedBinaryPath = path.join(context.appOutDir, `${EXECUTABLE_NAME}.bin`);

  if (!fs.existsSync(wrappedBinaryPath)) {
    if (!fs.existsSync(executablePath)) {
      throw new Error(`Expected Linux executable at ${executablePath}`);
    }

    fs.renameSync(executablePath, wrappedBinaryPath);
    console.log(`Renamed ${EXECUTABLE_NAME} to ${EXECUTABLE_NAME}.bin for Linux wrapper`);
  }

  fs.writeFileSync(executablePath, WRAPPER_SCRIPT, { mode: WRAPPER_MODE });
  fs.chmodSync(executablePath, WRAPPER_MODE);
  console.log(`Created Linux wrapper for ${EXECUTABLE_NAME} with --no-sandbox`);
};