// -*- indent-tabs-mode: nil; js-indent-level: 2 -*-
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

const { classes: Cc, interfaces: Ci, utils: Cu, results: Cr } = Components;

Cu.import("resource://gre/modules/XPCOMUtils.jsm");
Cu.import("resource://gre/modules/Services.jsm");

XPCOMUtils.defineLazyModuleGetter(this, "Downloads",
                                  "resource://gre/modules/Downloads.jsm");

XPCOMUtils.defineLazyModuleGetter(this, "Task",
                                  "resource://gre/modules/Task.jsm");

// -----------------------------------------------------------------------
// HelperApp Launcher Dialog
//
// For now on b2g we never prompt and just download to the default
// location.
//
// -----------------------------------------------------------------------

function HelperAppLauncherDialog() { }

HelperAppLauncherDialog.prototype = {
  classID: Components.ID("{710322af-e6ae-4b0c-b2c9-1474a87b077e}"),
  QueryInterface: XPCOMUtils.generateQI([Ci.nsIHelperAppLauncherDialog]),

  show: function(aLauncher, aContext, aReason) {
    aLauncher.MIMEInfo.preferredAction = Ci.nsIMIMEInfo.saveToDisk;
    aLauncher.saveToDisk(null, false);
  },

  promptForSaveToFile: function(aLauncher,
                                aContext,
                                aDefaultFile,
                                aSuggestedFileExt,
                                aForcePrompt) {
    throw Cr.NS_ERROR_NOT_AVAILABLE;
  },

  promptForSaveToFileAsync: function(aLauncher,
                                     aContext,
                                     aDefaultFile,
                                     aSuggestedFileExt,
                                     aForcePrompt) {
    // Retrieve the user's default download directory.
    Task.spawn(function() {
      let file = null;
      try {
        let defaultFolder = yield Downloads.getPreferredDownloadsDirectory();
        let dir = Cc["@mozilla.org/file/local;1"].createInstance(Ci.nsIFile);
        dir.initWithPath(defaultFolder);
        file = this.validateLeafName(dir, aDefaultFile, aSuggestedFileExt);
      } catch(e) { }
      aLauncher.saveDestinationAvailable(file);
    }.bind(this)).then(null, Cu.reportError);
  },

  validateLeafName: function(aLocalFile, aLeafName, aFileExt) {
    if (!(aLocalFile && this.isUsableDirectory(aLocalFile)))
      return null;

    // Remove any leading periods, since we don't want to save hidden files
    // automatically.
    aLeafName = aLeafName.replace(/^\.+/, "");

    if (aLeafName == "")
      aLeafName = "unnamed" + (aFileExt ? "." + aFileExt : "");
    aLocalFile.append(aLeafName);

    this.makeFileUnique(aLocalFile);
    return aLocalFile;
  },

  makeFileUnique: function(aLocalFile) {
    try {
      // Note - this code is identical to that in
      //   toolkit/content/contentAreaUtils.js.
      // If you are updating this code, update that code too! We can't share code
      // here since this is called in a js component.
      let collisionCount = 0;
      while (aLocalFile.exists()) {
        collisionCount++;
        if (collisionCount == 1) {
          // Append "(2)" before the last dot in (or at the end of) the filename
          // special case .ext.gz etc files so we don't wind up with .tar(2).gz
          if (aLocalFile.leafName.match(/\.[^\.]{1,3}\.(gz|bz2|Z)$/i))
            aLocalFile.leafName = aLocalFile.leafName.replace(/\.[^\.]{1,3}\.(gz|bz2|Z)$/i, "(2)$&");
          else
            aLocalFile.leafName = aLocalFile.leafName.replace(/(\.[^\.]*)?$/, "(2)$&");
        }
        else {
          // replace the last (n) in the filename with (n+1)
          aLocalFile.leafName = aLocalFile.leafName.replace(/^(.*\()\d+\)/, "$1" + (collisionCount+1) + ")");
        }
      }
      aLocalFile.create(Ci.nsIFile.NORMAL_FILE_TYPE, 0600);
    }
    catch (e) {
      dump("*** exception in makeFileUnique: " + e + "\n");

      if (e.result == Cr.NS_ERROR_FILE_ACCESS_DENIED)
        throw e;

      if (aLocalFile.leafName == "" || aLocalFile.isDirectory()) {
        aLocalFile.append("unnamed");
        if (aLocalFile.exists())
          aLocalFile.createUnique(Ci.nsIFile.NORMAL_FILE_TYPE, 0600);
      }
    }
  },

  isUsableDirectory: function(aDirectory) {
    return aDirectory.exists() &&
           aDirectory.isDirectory() &&
           aDirectory.isWritable();
  },
};

this.NSGetFactory = XPCOMUtils.generateNSGetFactory([HelperAppLauncherDialog]);
