// @ts-check
const { createRunOncePlugin, withDangerousMod } = require("@expo/config-plugins");
const fs = require("fs");
const path = require("path");

const pkg = require("expo-mlkit-ocr/package.json");

const DISABLE_LINE = "ENV['EXPO_MLKIT_OCR_DISABLE_MLKIT'] = '1'";
const MARKER = "expo-mlkit-ocr: iOS Simulator MLKit handling";

function resolveIosEngine(props = {}) {
  const raw = props.iosEngine ?? "auto";
  return raw === "auto" || raw === "mlkit" || raw === "vision" ? raw : "auto";
}

function stripMarkedBlock(podfile) {
  const lines = podfile.split(/\r?\n/);
  const next = [];

  for (let i = 0; i < lines.length; i += 1) {
    const line = lines[i];
    if (!line.includes(MARKER)) {
      next.push(line);
      continue;
    }

    const markerIndent = (line.match(/^\s*/) ?? [""])[0].length;
    while (i + 1 < lines.length) {
      i += 1;
      const candidate = lines[i];
      const candidateIndent = (candidate.match(/^\s*/) ?? [""])[0].length;
      if (candidate.trim() === "end" && candidateIndent <= markerIndent) {
        break;
      }
    }
  }

  return next.join("\n");
}

function stripOrphanedMlkitArchPatch(podfile) {
  return podfile
    .replace(
      /\n\s*end\s*\n\s*\n\s*installer\.aggregate_targets\.each do \|aggregate_target\|[\s\S]*?aggregate_target\.user_project\.save\s*\n\s*end\s*\n/g,
      "\n",
    )
    .replace(
      /\n\s*if ENV\['EXPO_MLKIT_OCR_DISABLE_MLKIT'\] == '1'\s*\n\s*installer\.pods_project\.targets\.each do \|target\|[\s\S]*?\n\s*end\s*\n/g,
      "\n",
    );
}

function insertDisableLine(podfile) {
  const lines = podfile
    .split(/\r?\n/)
    .filter((line) => line.trim() !== DISABLE_LINE);

  let insertAt = 0;
  while (insertAt < lines.length && lines[insertAt].trim().startsWith("#")) {
    insertAt += 1;
  }

  lines.splice(insertAt, 0, DISABLE_LINE);
  return lines.join("\n");
}

/** @type {import('@expo/config-plugins').ConfigPlugin<{ iosEngine?: "auto" | "mlkit" | "vision", disableMlkitOnSimulator?: boolean }>} */
function withExpoMlkitOcrEnv(config, props = {}) {
  return withDangerousMod(config, [
    "ios",
    async (config) => {
      const podfilePath = path.join(config.modRequest.platformProjectRoot, "Podfile");
      if (!fs.existsSync(podfilePath)) {
        return config;
      }

      const iosEngine = resolveIosEngine(props);
      const shouldDisableMlkit =
        iosEngine !== "mlkit" || props.disableMlkitOnSimulator === true;

      let podfile = fs.readFileSync(podfilePath, "utf8");
      podfile = stripMarkedBlock(podfile);
      podfile = stripOrphanedMlkitArchPatch(podfile);

      if (shouldDisableMlkit) {
        podfile = insertDisableLine(podfile);
      } else {
        podfile = podfile
          .split(/\r?\n/)
          .filter((line) => line.trim() !== DISABLE_LINE)
          .join("\n");
      }

      fs.writeFileSync(podfilePath, podfile.endsWith("\n") ? podfile : `${podfile}\n`);
      return config;
    },
  ]);
}

module.exports = createRunOncePlugin(
  withExpoMlkitOcrEnv,
  "beenvoice-expo-mlkit-ocr-env",
  pkg.version,
);