/* 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/. */

this.EXPORTED_SYMBOLS = ["MockFilePicker"];

const Cc = Components.classes;
const Ci = Components.interfaces;
const Cm = Components.manager;
const Cu = Components.utils;

const CONTRACT_ID = "@mozilla.org/filepicker;1";

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

// Allow stuff from this scope to be accessed from non-privileged scopes. This
// would crash if used outside of automation.
Cu.forcePermissiveCOWs();

var registrar = Cm.QueryInterface(Ci.nsIComponentRegistrar);
var oldClassID, oldFactory;
var newClassID = Cc["@mozilla.org/uuid-generator;1"].getService(Ci.nsIUUIDGenerator).generateUUID();
var newFactory = function(window) {
  return {
    createInstance(aOuter, aIID) {
      if (aOuter)
        throw Components.results.NS_ERROR_NO_AGGREGATION;
      return new MockFilePickerInstance(window).QueryInterface(aIID);
    },
    lockFactory(aLock) {
      throw Components.results.NS_ERROR_NOT_IMPLEMENTED;
    },
    QueryInterface: XPCOMUtils.generateQI([Ci.nsIFactory])
  };
};

this.MockFilePicker = {
  returnOK: Ci.nsIFilePicker.returnOK,
  returnCancel: Ci.nsIFilePicker.returnCancel,
  returnReplace: Ci.nsIFilePicker.returnReplace,

  filterAll: Ci.nsIFilePicker.filterAll,
  filterHTML: Ci.nsIFilePicker.filterHTML,
  filterText: Ci.nsIFilePicker.filterText,
  filterImages: Ci.nsIFilePicker.filterImages,
  filterXML: Ci.nsIFilePicker.filterXML,
  filterXUL: Ci.nsIFilePicker.filterXUL,
  filterApps: Ci.nsIFilePicker.filterApps,
  filterAllowURLs: Ci.nsIFilePicker.filterAllowURLs,
  filterAudio: Ci.nsIFilePicker.filterAudio,
  filterVideo: Ci.nsIFilePicker.filterVideo,

  window: null,
  pendingPromises: [],

  init(window) {
    this.window = window;

    this.reset();
    this.factory = newFactory(window);
    if (!registrar.isCIDRegistered(newClassID)) {
      oldClassID = registrar.contractIDToCID(CONTRACT_ID);
      oldFactory = Cm.getClassObject(Cc[CONTRACT_ID], Ci.nsIFactory);
      registrar.unregisterFactory(oldClassID, oldFactory);
      registrar.registerFactory(newClassID, "", CONTRACT_ID, this.factory);
    }
  },

  reset() {
    this.appendFilterCallback = null;
    this.appendFiltersCallback = null;
    this.displayDirectory = null;
    this.displaySpecialDirectory = "";
    this.filterIndex = 0;
    this.mode = null;
    this.returnData = [];
    this.returnValue = null;
    this.showCallback = null;
    this.afterOpenCallback = null;
    this.shown = false;
    this.showing = false;
  },

  cleanup() {
    var previousFactory = this.factory;
    this.reset();
    this.factory = null;
    if (oldFactory) {
      registrar.unregisterFactory(newClassID, previousFactory);
      registrar.registerFactory(oldClassID, "", CONTRACT_ID, oldFactory);
    }
  },

  internalFileData(obj) {
    return {
      nsIFile: "nsIFile" in obj ? obj.nsIFile : null,
      domFile: "domFile" in obj ? obj.domFile : null,
      domDirectory: "domDirectory" in obj ? obj.domDirectory : null,
    };
  },

  useAnyFile() {
    var file = FileUtils.getDir("TmpD", [], false);
    file.append("testfile");
    file.createUnique(Ci.nsIFile.NORMAL_FILE_TYPE, 0o644);
    let promise = this.window.File.createFromNsIFile(file)
                  .then(domFile => domFile, () => null)
                  // domFile can be null.
                  .then(domFile => {
                    this.returnData = [this.internalFileData({ nsIFile: file, domFile })];
                  }).then(() => file);

    this.pendingPromises = [promise];

    // We return a promise in order to support some existing mochitests.
    return promise;
  },

  useBlobFile() {
    var blob = new this.window.Blob([]);
    var file = new this.window.File([blob], "helloworld.txt", { type: "plain/text" });
    this.returnData = [this.internalFileData({ domFile: file })];
    this.pendingPromises = [];
  },

  useDirectory(aPath) {
    var directory = new this.window.Directory(aPath);
    this.returnData = [this.internalFileData({ domDirectory: directory })];
    this.pendingPromises = [];
  },

  setFiles(files) {
    this.returnData = [];
    this.pendingPromises = [];

    for (let file of files) {
      if (file instanceof this.window.File) {
        this.returnData.push(this.internalFileData({ domFile: file }));
      } else {
        let promise = this.window.File.createFromNsIFile(file, { existenceCheck: false });

        promise.then(domFile => {
          this.returnData.push(this.internalFileData({ nsIFile: file, domFile }));
        });
        this.pendingPromises.push(promise);
      }
    }
  },

  getNsIFile() {
    if (this.returnData.length >= 1) {
      return this.returnData[0].nsIFile;
    }
    return null;
  }
};

function MockFilePickerInstance(window) {
  this.window = window;
}
MockFilePickerInstance.prototype = {
  QueryInterface: XPCOMUtils.generateQI([Ci.nsIFilePicker]),
  init(aParent, aTitle, aMode) {
    MockFilePicker.mode = aMode;
    this.filterIndex = MockFilePicker.filterIndex;
    this.parent = aParent;
  },
  appendFilter(aTitle, aFilter) {
    if (typeof MockFilePicker.appendFilterCallback == "function")
      MockFilePicker.appendFilterCallback(this, aTitle, aFilter);
  },
  appendFilters(aFilterMask) {
    if (typeof MockFilePicker.appendFiltersCallback == "function")
      MockFilePicker.appendFiltersCallback(this, aFilterMask);
  },
  defaultString: "",
  defaultExtension: "",
  parent: null,
  filterIndex: 0,
  displayDirectory: null,
  displaySpecialDirectory: "",
  get file() {
    if (MockFilePicker.returnData.length >= 1) {
      return MockFilePicker.returnData[0].nsIFile;
    }

    return null;
  },

  // We don't support directories here.
  get domFileOrDirectory() {
    if (MockFilePicker.returnData.length < 1) {
      return null;
    }

    if (MockFilePicker.returnData[0].domFile) {
      return MockFilePicker.returnData[0].domFile;
    }

    if (MockFilePicker.returnData[0].domDirectory) {
      return MockFilePicker.returnData[0].domDirectory;
    }

    return null;
  },
  get fileURL() {
    if (MockFilePicker.returnData.length >= 1 &&
        MockFilePicker.returnData[0].nsIFile) {
      return Services.io.newFileURI(MockFilePicker.returnData[0].nsIFile);
    }

    return null;
  },
  get files() {
    return {
      index: 0,
      QueryInterface: XPCOMUtils.generateQI([Ci.nsISimpleEnumerator]),
      hasMoreElements() {
        return this.index < MockFilePicker.returnData.length;
      },
      getNext() {
        if (!MockFilePicker.returnData[this.index].nsIFile) {
          return null;
        }
        return MockFilePicker.returnData[this.index++].nsIFile;
      }
    };
  },
  get domFileOrDirectoryEnumerator() {
    this.parent.QueryInterface(Ci.nsIInterfaceRequestor)
               .getInterface(Ci.nsIDOMWindowUtils);
    return {
      index: 0,
      QueryInterface: XPCOMUtils.generateQI([Ci.nsISimpleEnumerator]),
      hasMoreElements() {
        return this.index < MockFilePicker.returnData.length;
      },
      getNext() {
        // window.File does not implement nsIFile
        if (MockFilePicker.returnData[this.index].domFile) {
          return MockFilePicker.returnData[this.index++].domFile;
        }

        if (MockFilePicker.returnData[this.index].domDirectory) {
          return MockFilePicker.returnData[this.index++].domDirectory;
        }

        return null;
      }
    };
  },
  open(aFilePickerShownCallback) {
    MockFilePicker.showing = true;
    this.window.setTimeout(() => {
      // Maybe all the pending promises are already resolved, but we want to be sure.
      Promise.all(MockFilePicker.pendingPromises).then(() => {
        return Ci.nsIFilePicker.returnOK;
      }, () => {
        return Ci.nsIFilePicker.returnCancel;
      }).then(result => {
        // Nothing else has to be done.
        MockFilePicker.pendingPromises = [];

        if (result == Ci.nsIFilePicker.returnCancel) {
          return result;
        }

        MockFilePicker.displayDirectory = this.displayDirectory;
        MockFilePicker.displaySpecialDirectory = this.displaySpecialDirectory;
        MockFilePicker.shown = true;
        if (typeof MockFilePicker.showCallback == "function") {
          try {
            var returnValue = MockFilePicker.showCallback(this);
            if (typeof returnValue != "undefined") {
              return returnValue;
            }
          } catch (ex) {
            return Ci.nsIFilePicker.returnCancel;
          }
        }

        return MockFilePicker.returnValue;
      }).then(result => {
        // Some additional result file can be set by the callback. Let's
        // resolve the pending promises again.
        return Promise.all(MockFilePicker.pendingPromises).then(() => {
          return result;
        }, () => {
          return Ci.nsIFilePicker.returnCancel;
        });
      }).then(result => {
        MockFilePicker.pendingPromises = [];

        if (aFilePickerShownCallback) {
          aFilePickerShownCallback.done(result);
        }

        if (typeof MockFilePicker.afterOpenCallback == "function") {
          this.window.setTimeout(() => {
            MockFilePicker.afterOpenCallback(this);
          }, 0);
        }
      });
    });
  }
};
