// import-flow.js — v2.1.6
// premierepro API: docs say sync, runtime returns Promises. Await everything.

(function () {
  const Import = {};

  const fs = require('fs');
  // window.path is a UXP global (v6.4+) — no require('path')
  let os; try { os = require('os'); } catch (_) { os = {}; }
  let uxpFs; try { uxpFs = require('uxp').storage.localFileSystem; } catch (_) { uxpFs = null; }

  // ── Temp folder ──────────────────────────────────────────────────
  async function _getTempBase() {
    if (uxpFs && uxpFs.getTemporaryFolder) {
      try {
        const tmp = await uxpFs.getTemporaryFolder();
        if (tmp && tmp.nativePath) return tmp.nativePath;
      } catch (_) {}
    }
    try {
      const e = (typeof process !== 'undefined' && process.env) || {};
      if (e.TEMP && e.TEMP.length) return e.TEMP;
      if (e.TMP  && e.TMP.length)  return e.TMP;
      if (e.LOCALAPPDATA) return e.LOCALAPPDATA + '\\Temp';
    } catch (_) {}
    try {
      if (os.homedir) {
        const h = os.homedir();
        if (h) return h + '\\AppData\\Local\\Temp';
      }
    } catch (_) {}
    throw new Error('Cannot find writable temp folder');
  }

  Import._tempPath = async function (safeName) {
    const base = await _getTempBase();
    return path.join(base, 'dragonflight-' + safeName);
  };

  // Returns true if the path already exists on disk.
  Import._fileExists = async function (filePath) {
    try { await fs.stat(filePath); return true; } catch (_) { return false; }
  };

  // Write ArrayBuffer to disk via fs.writeFile.
  // If the file is locked (EBUSY — Premiere already has it open from a
  // previous import) we treat that as success: the bytes are already there.
  Import._writeBuffer = async function (destPath, arrayBuffer) {
    try {
      await fs.writeFile(destPath, arrayBuffer);
    } catch (e) {
      const busy = e.code === 'EBUSY' || /resource busy/i.test(String(e.message));
      if (!busy) throw e;
      // File locked by Premiere — it's already there, proceed.
      console.warn('[df] _writeBuffer EBUSY on', destPath, '— using existing file');
    }
    return destPath;
  };

  // Fetch — no redirect option (not supported in UXP)
  // addAuth: only for same-origin proxy URLs, NOT for S3 presigned URLs
  async function _fetch(url, addAuth) {
    const headers = {};
    if (addAuth && API.state.apiToken) {
      headers['Authorization'] = 'Bearer ' + API.state.apiToken;
    }
    const r = await fetch(url, { headers });
    if (!r.ok) throw new Error('HTTP ' + r.status + ' fetching ' + url);
    return r;
  }

  // ── premierepro lazy require ─────────────────────────────────────
  function _ppro() {
    if (Import._ppro_mod) return Import._ppro_mod;
    try { Import._ppro_mod = require('premierepro'); }
    catch (e) { throw new Error('UXP premierepro unavailable: ' + e.message); }
    return Import._ppro_mod;
  }

  // Import a file into the active Premiere project.
  // ALL premierepro calls must be awaited — runtime returns Promises
  // even though docs list them as synchronous.
  // importFiles returns false when the file is already in the project — not an error.
  Import.importIntoProject = async function (filePath) {
    const P = _ppro();
    const project = await P.Project.getActiveProject();
    if (!project) throw new Error('No active Premiere project');
    const root = await project.getRootItem();
    await project.importFiles([filePath], true, root, false);
    // Return value false = already in project. Either way, we're done.
    return true;
  };

  // ── Proxy import ─────────────────────────────────────────────────
  Import.proxy = async function (asset) {
    const safeName = UI.sanitizeFilename((asset.display_name || asset.filename || asset.id) + '.mp4');
    const dest     = await Import._tempPath(safeName);

    const alreadyOnDisk = await Import._fileExists(dest);
    if (alreadyOnDisk) {
      // File exists from a previous import — skip download, just (re-)import.
      UI.showProgress('Importing into Premiere…', 92);
    } else {
      UI.showProgress('Resolving proxy URL…', 4);
      const { url } = await API.getProxyUrl(asset.id);

      UI.showProgress('Downloading ' + safeName + '…', 10);
      const r = await _fetch(url, true);   // same-origin — add auth

      UI.showProgress('Writing to disk…', 70);
      const buf = await r.arrayBuffer();
      await Import._writeBuffer(dest, buf);

      UI.showProgress('Importing into Premiere…', 92);
    }

    await Import.importIntoProject(dest);
    UI.hideProgress();
    UI.toast('Imported: ' + safeName, 'ok');
    return { localPath: dest, safeName };
  };

  // ── Hi-Res import ────────────────────────────────────────────────
  Import.hires = async function (asset) {
    UI.showProgress('Resolving hi-res URL…', 4);
    const info     = await API.getHiresInfo(asset.id);
    const safeName = UI.sanitizeFilename(info.filename || (asset.display_name || asset.id) + '.' + (info.ext || 'mxf'));
    const dest     = await Import._tempPath(safeName);

    const alreadyOnDisk = await Import._fileExists(dest);
    if (alreadyOnDisk) {
      UI.showProgress('Importing into Premiere…', 92);
    } else {
      UI.showProgress('Downloading ' + safeName + ' (' + UI.formatBytes(Number(info.file_size || 0)) + ')…', 8);
      const r = await _fetch(info.url, false);  // presigned S3 — no auth

      UI.showProgress('Writing to disk…', 75);
      const buf = await r.arrayBuffer();
      await Import._writeBuffer(dest, buf);

      UI.showProgress('Importing into Premiere…', 92);
    }

    await Import.importIntoProject(dest);
    UI.hideProgress();
    UI.toast('Hi-res imported: ' + safeName, 'ok');
    return { localPath: dest, safeName };
  };

  // Used by timeline.js batch relink
  Import._streamToFile = async function (response, destPath /*, onProgress */) {
    const buf = await response.arrayBuffer();
    await Import._writeBuffer(destPath, buf);
    return destPath;
  };

  window.Import = Import;
})();