// ai slop

import fs from "node:fs";
import path from "node:path";

const DEV = process.argv.includes("--dev");

const escape = (str) =>
  str.replace(/\s+/g, " ").trim().replace(/"/g, '\\"').replace(/\$/g, "\\$");

function build() {
  const data = fs.readFileSync("./script.php", "utf8");
  const mountRegex = /"<<BUILDER_MOUNT_FILE_\((?<file>.*?)\)>>"/gm;
  const mountedFiles = new Set();

  const result = data.replace(mountRegex, (_match, file) => {
    let fileContent = fs.readFileSync(file.replace(/\\/g, "/"), "utf8");
    mountedFiles.add(path.resolve(file));

    const inlinePhpVarRegex = /"<<BUILDER_PHP_VAR\((?<varName>.*?)\)>>"/g;
    const vars = [];
    let varMatch;
    while ((varMatch = inlinePhpVarRegex.exec(fileContent)) !== null) {
      vars.push({
        escapedPlaceholder: escape(varMatch[0]),
        varName: varMatch.groups.varName,
      });
    }

    fileContent = escape(fileContent);

    for (const { escapedPlaceholder, varName } of vars) {
      fileContent = fileContent.replace(
        escapedPlaceholder,
        `" . ${varName} . "`,
      );
    }

    return `"${fileContent}"`;
  });

  fs.writeFileSync("./output.php", result, "utf8");
  console.log(`[${new Date().toLocaleTimeString()}] Built output.php`);

  return mountedFiles;
}

// Run once immediately
let watchedFiles = build();

if (DEV) {
  const watchers = new Map(); // path → FSWatcher

  function watchFile(file) {
    if (watchers.has(file)) return;
    const watcher = fs.watch(file, () => {
      console.log(
        `[${new Date().toLocaleTimeString()}] Changed: ${path.relative(".", file)}`,
      );
      rebuild();
    });
    watchers.set(file, watcher);
  }

  function syncWatchers(current) {
    // Watch any newly mounted files
    for (const file of current) watchFile(file);

    // Stop watching files that are no longer mounted
    for (const [file, watcher] of watchers) {
      if (!current.has(file) && file !== path.resolve("./script.php")) {
        watcher.close();
        watchers.delete(file);
      }
    }
  }

  function rebuild() {
    try {
      watchedFiles = build();
      syncWatchers(watchedFiles);
    } catch (err) {
      console.error("Build error:", err.message);
    }
  }

  // Always watch the entry file
  watchFile(path.resolve("./script.php"));
  syncWatchers(watchedFiles);

  console.log("Watching for changes… (Ctrl+C to stop)");
}