import { execSync } from "node:child_process";
import type { MigrationContext } from "../types";

/**
 * Fleet-wide canonical bun version. Bumped here propagates to all newly
 * migrated sites via the `packageManager` field AND the
 * `lockfile-check.yml` workflow's `bun-version` input. See
 * MIGRATION_TOOLING_PLAN.md for the bun-canonical decision.
 *
 * Exported because the lockfile-check workflow template reads it
 * directly to keep both files in lockstep.
 */
export const CANONICAL_BUN_VERSION = "1.3.5";

/**
 * Fleet-wide canonical Node version. Used by the scaffolded CI / Playwright
 * workflows' setup-node step (kept in lockstep with the perf workflow's pinned
 * node-version). 22.15 is the floor for @cloudflare/vite-plugin's
 * module.registerHooks.
 */
export const CANONICAL_NODE_VERSION = "22.15.0";

/**
 * Get the latest published version of an npm package.
 * Falls back to the provided default if the lookup fails.
 */
function getLatestVersion(pkg: string, fallback: string): string {
  try {
    const version = execSync(`npm view ${pkg} version`, {
      encoding: "utf-8",
      timeout: 10000,
      stdio: ["pipe", "pipe", "pipe"],
    }).trim();
    return version || fallback;
  } catch {
    return fallback;
  }
}

/**
 * Extract npm dependencies from deno.json import map.
 * Entries like `"fuse.js": "npm:fuse.js@7.0.0"` become `"fuse.js": "^7.0.0"`.
 */
function extractNpmDeps(importMap: Record<string, string>): Record<string, string> {
  const deps: Record<string, string> = {};
  const SKIP_KEYS = new Set([
    "daisyui", "preact-render-to-string", "simple-git", "fast-json-patch",
    "postcss", "cssnano", "partytown",
  ]);
  for (const [key, value] of Object.entries(importMap)) {
    // Skip framework deps we handle ourselves
    if (key.startsWith("preact") || key.startsWith("@preact/")) continue;
    if (key.startsWith("@deco/")) continue;
    if (key.startsWith("@biomejs/")) continue;
    if (key.startsWith("firebase/")) continue;
    if (SKIP_KEYS.has(key)) continue;

    // npm: protocol — direct npm import
    if (value.startsWith("npm:")) {
      const raw = value.slice(4);
      const atIdx = raw.lastIndexOf("@");
      if (atIdx <= 0) {
        deps[raw] = "*";
      } else {
        const name = raw.slice(0, atIdx);
        let version = raw.slice(atIdx + 1);
        if (/^[~^>=<]/.test(version)) {
          deps[name] = version;
        } else {
          deps[name] = `^${version}`;
        }
      }
      continue;
    }

    // esm.sh URLs — extract package name and version
    const esmMatch = value.match(/esm\.sh\/(@?[^@?]+)@([^?/]+)/);
    if (esmMatch) {
      const [, name, version] = esmMatch;
      if (name.startsWith("preact") || name.startsWith("@preact/")) continue;
      deps[name] = `^${version}`;
      continue;
    }
  }
  return deps;
}

export function generatePackageJson(ctx: MigrationContext): string {
  const extractedDeps = {
    ...extractNpmDeps(ctx.importMap),
    ...ctx.discoveredNpmDeps,
  };

  // Consolidate firebase/* split imports into single package
  const hasFirebase = Object.keys(ctx.importMap).some((k) => k.startsWith("firebase"));
  if (hasFirebase && !extractedDeps["firebase"]) {
    extractedDeps["firebase"] = "^12.10.0";
  }
  // Remove wildcard versions
  for (const [k, v] of Object.entries(extractedDeps)) {
    if (v === "^*" || v === "*") extractedDeps[k] = "latest";
  }

  const siteDeps = extractedDeps;

  // @decocms/blocks, @decocms/blocks-admin, @decocms/blocks-cli,
  // @decocms/tanstack, and the @decocms/apps-* platform packages are
  // published in lockstep from the same monorepo release, so a single
  // version lookup covers all of them (mirrors how consumer sites bump
  // "@decocms/blocks/blocks-admin/nextjs ranges" together).
  //
  // If this ever stops being true (e.g. a package starts shipping
  // independent version bumps), every `${frameworkVersion}` usage below
  // (in `dependencies` and `devDependencies`) needs to become its own
  // `getLatestVersion("<package>", "<fallback>")` call instead of sharing
  // this one lookup.
  const frameworkVersion = getLatestVersion("@decocms/blocks", "7.5.1");

  const platformPackage: Partial<Record<typeof ctx.platform, string>> = {
    vtex: "@decocms/apps-vtex",
    shopify: "@decocms/apps-shopify",
    magento: "@decocms/apps-magento",
  };
  const platformDep = platformPackage[ctx.platform];

  const pkg = {
    name: ctx.siteName,
    version: "0.1.0",
    type: "module",
    description: `${ctx.siteName} storefront powered by TanStack Start`,
    scripts: {
      dev: "vite dev",
      "dev:clean":
        "rm -rf node_modules/.vite .wrangler/state .tanstack && vite dev",
      // ONE incremental orchestrator instead of the old 5-script chain
      // (generate-blocks/sections/loaders/schema/invoke). It runs the same
      // generators — concurrently, skipping the ones whose inputs didn't
      // change — and the individual scripts stay available under
      // node_modules/@decocms/blocks-cli/scripts/ for one-off runs. Sites
      // chain their own extra tools (tsr, graphql-codegen, tailwind) around
      // this command themselves.
      generate: `tsx node_modules/@decocms/blocks-cli/scripts/generate.ts --site ${ctx.siteName} --exclude vtex/loaders,vtex/actions,loaders/vtex-auth-loader,loaders/reviews/productReviews,loaders/product/buyTogether,loaders/search/productListPageCollection,loaders/search/intelligenseSearch,loaders/Layouts/ProductCard`,
      "generate:routes": "tsr generate",
      build: "npm run generate && tsr generate && vite build",
      preview: "vite preview",
      // Deploy is owned by Cloudflare Workers Builds (D6.3); the
      // repo<->worker connection is configured per-worker in the CF
      // dashboard. Local devs use plain `wrangler` against the
      // committed wrangler.jsonc.
      deploy: "wrangler deploy",
      types: "wrangler types",
      typecheck: "tsc --noEmit",
      format: 'prettier --write "src/**/*.{ts,tsx}"',
      "format:check": 'prettier --check "src/**/*.{ts,tsx}"',
      knip: "knip",
      "test:e2e": "playwright test",
      clean:
        "rm -rf node_modules .cache dist .wrangler/state node_modules/.vite && bun install",
      "tailwind:lint":
        "tsx scripts/tailwind-lint.ts",
      "tailwind:fix":
        "tsx scripts/tailwind-lint.ts --fix",
    },
    author: "deco.cx",
    license: "MIT",
    packageManager: `bun@${CANONICAL_BUN_VERSION}`,
    dependencies: {
      "@decocms/blocks": `^${frameworkVersion}`,
      "@decocms/blocks-admin": `^${frameworkVersion}`,
      "@decocms/tanstack": `^${frameworkVersion}`,
      "@decocms/apps-commerce": `^${frameworkVersion}`,
      ...(platformDep ? { [platformDep]: `^${frameworkVersion}` } : {}),
      "@tanstack/react-query": "5.90.21",
      "@tanstack/react-router": "1.166.7",
      "@tanstack/react-start": "1.166.8",
      "@tanstack/react-store": "0.9.2",
      "@tanstack/store": "0.9.2",
      "colorjs.io": "^0.6.1",
      react: "^19.2.4",
      "react-dom": "^19.2.4",
      ...siteDeps,
    },
    devDependencies: {
      "@cloudflare/vite-plugin": "^1.27.0",
      "@decocms/blocks-cli": `^${frameworkVersion}`,
      "@playwright/test": "^1.62.1",
      // CLI build of src/styles/app.css — used by the migration's own
      // css-compile-check.ts (phase-compile) and by `tailwind:lint`, so a
      // dropped custom theme token fails migration/CI instead of shipping
      // an unstyled page (decocms/blocks#369).
      "@tailwindcss/cli": "^4.2.1",
      "@tailwindcss/vite": "^4.2.1",
      "@tanstack/router-cli": "1.166.7",
      "@types/react": "^19.2.14",
      "@types/react-dom": "^19.2.3",
      "@vitejs/plugin-react": "^5.1.4",
      "babel-plugin-react-compiler": "^1.0.0",
      "daisyui": "^5.5.19",
      knip: "^5.61.2",
      prettier: "^3.5.3",
      tailwindcss: "^4.2.1",
      "ts-morph": "^27.0.2",
      tsx: "^4.19.4",
      typescript: "^5.9.3",
      vite: "^7.3.1",
      wrangler: "^4.72.0",
    },
  };

  return JSON.stringify(pkg, null, 2) + "\n";
}