file_manager: Move non-binding code to c/b/chromeos/file_manager

chrome/browser/chromeos/extensions/file_manager/file_tasks.h

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-//
-// This file provides utility functions for "file tasks".
-//
-// WHAT ARE FILE TASKS?
-//
-// File tasks are representatiosn of actions that can be performed over the
-// currently selected files from Files.app. A task can be either of:
-//
-// 1) Chrome extension or app, registered via "file_handlers" or
-// "file_browser_handlers" in manifest.json (ex. Text.app). This information
-// comes from FileBrowserHandler::GetHandlers()
-//
-// See also:
-// https://developer.chrome.com/extensions/manifest.html#file_handlers
-// https://developer.chrome.com/extensions/fileBrowserHandler.html
-//
-// 2) Built-in handlers provided from Files.app. Files.app provides lots of
-// file_browser_handlers, such as "play", "watch", "mount-archive".  These
-// built-in handlers are often handled in special manners inside Files.app.
-// This information also comes from FileBrowserHandler::GetHandlers().
-//
-// See also:
-// chrome/browser/resources/file_manager/manifest.json
-//
-// 3) Drive app, which is a hosted app (i.e. just web site), that can work
-// with Drive (ex. Pixlr Editor). This information comes from
-// drive::DriveAppRegistry.
-//
-// See also:
-// https://chrome.google.com/webstore/category/collection/drive_apps
-//
-// For example, if the user is now selecting a JPEG file, Files.app will
-// receive file tasks represented as a JSON object via
-// chrome.fileBrowserPrivate.getFileTasks() API, which look like:
-//
-// [
-//   {
-//     "driveApp": true,
-//     "iconUrl": "<app_icon_url>",
-//     "isDefault": false,
-//     "taskId": "<drive_app_id>|drive|open-with",
-//     "title": "Drive App Name (ex. Pixlr Editor)"
-//   },
-//   {
-//     "driveApp": false,
-//     "iconUrl": "chrome://extension-icon/hhaomjibdihmijegdhdafkllkbggdgoj/16/1",
-//     "isDefault": true,
-//     "taskId": "hhaomjibdihmijegdhdafkllkbggdgoj|file|gallery",
-//     "title": "__MSG_OPEN_ACTION__"
-//   }
-// ]
-//
-// The first file task is a Drive app. The second file task is a built-in
-// handler from Files.app.
-//
-// WHAT ARE TASK IDS?
-//
-// You may have noticed that "taskId" fields in the above example look
-// awakard. Apparently "taskId" encodes three types of information delimited
-// by "|". This is a weird format for something called as an ID.
-//
-// 1) Why are the three types information encoded in this way?
-//
-// It's just a historical reason. The reason is that a simple string can be
-// easily stored in user's preferences. We should stop doing this, by storing
-// this information in chrome.storage instead. crbug.com/267359.
-//
-// 2) OK, then what are the three types of information encoded here?
-//
-// The task ID encodes the folloing structure:
-//
-//     <app-id>|<task-type>|<task-action-id>
-//
-// <app-id> is either of Chrome Extension/App ID or Drive App ID. For some
-// reason, Chrome Extension/App IDs and Drive App IDs look differently. As of
-// writing, the fomer looks like "hhaomjibdihmijegdhdafkllkbggdgoj"
-// (Files.app) and the latter looks like "419782477519" (Pixlr Editor).
-//
-// <task-type> is either of
-// - "file" - File browser handler - app/extension declaring
-//            "file_browser_handlers" in manifest.
-// - "app" - File handler - app declaring "file_handlers" in manifest.json.
-// - "drive" - Drive App
-//
-// <task-action-id> is an ID string used for identifying actions provided
-// from a single Chrome Extension/App. In other words, a single
-// Chrome/Extension can provide multiple file handlers hence each of them
-// needs to have a unique action ID.  For Drive apps, <task-action-id> is
-// always "open-with".
-//
-// HOW TASKS ARE EXECUTED?
-//
-// chrome.fileBrowserPrivate.viewFiles() is used to open a file in a browser,
-// without any handler. Browser will take care of handling the file (ex. PDF).
-//
-// chrome.fileBrowserPrivate.executeTasks() is used to open a file with a
-// handler (Chrome Extension/App or Drive App).
-//
-// Some built-in handlers such as "play" and "watch" are handled internally
-// in Files.app. "mount-archive" is handled very differently. The task
-// execution business should be simplified: crbug.com/267313
-//
-// See also:
-// chrome/browser/resources/file_manager/js/file_tasks.js
-//
-
-#ifndef CHROME_BROWSER_CHROMEOS_EXTENSIONS_FILE_MANAGER_FILE_TASKS_H_
-#define CHROME_BROWSER_CHROMEOS_EXTENSIONS_FILE_MANAGER_FILE_TASKS_H_
-
-#include <set>
-#include <string>
-#include <vector>
-
-#include "base/basictypes.h"
-#include "base/callback_forward.h"
-#include "chrome/browser/extensions/api/file_handlers/app_file_handler_util.h"
-#include "url/gurl.h"
-
-class PrefService;
-class Profile;
-
-namespace drive {
-class DriveAppRegistry;
-}
-
-namespace fileapi {
-class FileSystemURL;
-}
-
-namespace file_manager {
-namespace file_tasks {
-
-// Task types as explained in the comment above. Search for <task-type>.
-enum TaskType {
-  TASK_TYPE_FILE_BROWSER_HANDLER,
-  TASK_TYPE_FILE_HANDLER,
-  TASK_TYPE_DRIVE_APP,
-  TASK_TYPE_UNKNOWN,  // Used only for handling errors.
-};
-
-// Describes a task.
-// See the comment above for <app-id>, <task-type>, and <action-id>.
-struct TaskDescriptor {
-  TaskDescriptor(const std::string& in_app_id,
-                 TaskType in_task_type,
-                 const std::string& in_action_id)
-      : app_id(in_app_id),
-        task_type(in_task_type),
-        action_id(in_action_id) {
-  }
-  TaskDescriptor() {
-  }
-
-  std::string app_id;
-  TaskType task_type;
-  std::string action_id;
-};
-
-// Describes a task with extra information such as icon URL.
-class FullTaskDescriptor {
- public:
-  FullTaskDescriptor(const TaskDescriptor& task_descriptor,
-                     const std::string& task_title,
-                     const GURL& icon_url,
-                     bool is_default);
-  const TaskDescriptor& task_descriptor() const { return task_descriptor_; }
-
-  // The title of the task.
-  const std::string& task_title() { return task_title_; }
-  // The icon URL for the task (ex. app icon)
-  const GURL& icon_url() const { return icon_url_; }
-
-  // True if this task is set as default.
-  bool is_default() const { return is_default_; }
-  void set_is_default(bool is_default) { is_default_ = is_default; }
-
-  // Returns a DictionaryValue representation, which looks like:
-  //
-  // {
-  //   "iconUrl": "<app_icon_url>",
-  //   "isDefault": false,
-  //   "taskId": "<drive_app_id>|drive|open-with",
-  //   "title": "Drive App Name (ex. Pixlr Editor)"
-  // },
-  //
-  // "iconUrl" is omitted if icon_url_ is empty.
-  //
-  // This representation will be used to send task info to the JavaScript.
-  scoped_ptr<base::DictionaryValue> AsDictionaryValue() const;
-
- private:
-  TaskDescriptor task_descriptor_;
-  std::string task_title_;
-  GURL icon_url_;
-  bool is_default_;
-};
-
-// Update the default file handler for the given sets of suffixes and MIME
-// types.
-void UpdateDefaultTask(PrefService* pref_service,
-                       const std::string& task_id,
-                       const std::set<std::string>& suffixes,
-                       const std::set<std::string>& mime_types);
-
-// Returns the task ID of the default task for the given |mime_type|/|suffix|
-// combination. If it finds a MIME type match, then it prefers that over a
-// suffix match. If it a default can't be found, then it returns the empty
-// string.
-std::string GetDefaultTaskIdFromPrefs(const PrefService& pref_service,
-                                      const std::string& mime_type,
-                                      const std::string& suffix);
-
-// Generates task id for the task specified by |app_id|, |task_type| and
-// |action_id|.
-//
-// |app_id| is either of Chrome Extension/App ID or Drive App ID.
-// |action_id| is a free-form string ID for the action.
-std::string MakeTaskID(const std::string& app_id,
-                       TaskType task_type,
-                       const std::string& action_id);
-
-// Returns a task id for the Drive app with |app_id|.
-// TODO(gspencer): For now, the action id is always "open-with", but we
-// could add any actions that the drive app supports.
-std::string MakeDriveAppTaskId(const std::string& app_id);
-
-// Converts |task_descriptor| to a task ID.
-std::string TaskDescriptorToId(const TaskDescriptor& task_descriptor);
-
-// Parses the task ID and extracts app ID, task type, and action ID into
-// |task|. On failure, returns false, and the contents of |task| are
-// undefined.
-//
-// See also the comment at the beginning of the file for details for how
-// "task_id" looks like.
-bool ParseTaskID(const std::string& task_id, TaskDescriptor* task);
-
-// The callback is used for ExecuteFileTask(). Will be called with true if
-// the file task execution is successful, or false if unsuccessful.
-typedef base::Callback<void(bool success)> FileTaskFinishedCallback;
-
-// Executes file handler task for each element of |file_urls|.
-// Returns |false| if the execution cannot be initiated. Otherwise returns
-// |true| and then eventually calls |done| when all the files have been handled.
-// |done| can be a null callback.
-//
-// Parameters:
-// profile    - The profile used for making this function call.
-// app_id     - The ID of the app requesting the file task execution.
-// source_url - The source URL which originates this function call.
-// tab_id     - The ID of the tab which originates this function call.
-//              This can be 0 if no tab is associated.
-// task       - See the comment at TaskDescriptor struct.
-// file_urls  - URLs of the target files.
-// done       - The callback which will be called on completion.
-//              The callback won't be called if the function returns
-//              false.
-bool ExecuteFileTask(Profile* profile,
-                     const GURL& source_url,
-                     const std::string& app_id,
-                     int32 tab_id,
-                     const TaskDescriptor& task,
-                     const std::vector<fileapi::FileSystemURL>& file_urls,
-                     const FileTaskFinishedCallback& done);
-
-typedef extensions::app_file_handler_util::PathAndMimeTypeSet
-    PathAndMimeTypeSet;
-
-// Finds the Drive app tasks that can be used with the given |path_mime_set|
-// from |drive_app_registry|, and append them to the |result_list|.
-// Drive app tasks will be found only if all of the files are on Drive.
-void FindDriveAppTasks(const drive::DriveAppRegistry& drive_app_registry,
-                       const PathAndMimeTypeSet& path_mime_set,
-                       std::vector<FullTaskDescriptor>* result_list);
-
-// Finds the file handler tasks (apps declaring "file_handlers" in
-// manifest.json) that can be used with the given files, appending them to
-// the |result_list|.
-void FindFileHandlerTasks(Profile* profile,
-                          const PathAndMimeTypeSet& path_mime_set,
-                          std::vector<FullTaskDescriptor>* result_list);
-
-// Finds the file browser handler tasks (app/extensions declaring
-// "file_browser_handlers" in manifest.json) that can be used with the
-// given files, appending them to the |result_list|.
-void FindFileBrowserHandlerTasks(
-    Profile* profile,
-    const std::vector<GURL>& file_urls,
-    std::vector<FullTaskDescriptor>* result_list);
-
-// Finds all types (drive, file handlers, file browser handlers) of
-// tasks. See the comment at FindDriveAppTasks() about |result_list|.
-// Drive app tasks will be found only if all of the files are on Drive.
-void FindAllTypesOfTasks(
-    Profile* profile,
-    const PathAndMimeTypeSet& path_mime_set,
-    const std::vector<GURL>& file_urls,
-    std::vector<FullTaskDescriptor>* result_list);
-
-// Chooses the default task in |tasks| and sets it as default, if the default
-// task is found (i.e. the default task may not exist in |tasks|). No tasks
-// should be set as default before calling this function.
-void ChooseAndSetDefaultTask(const PrefService& pref_service,
-                             const PathAndMimeTypeSet& path_mime_set,
-                             std::vector<FullTaskDescriptor>* tasks);
-
-}  // namespace file_tasks
-}  // namespace file_manager
-
-#endif  // CHROME_BROWSER_CHROMEOS_EXTENSIONS_FILE_MANAGER_FILE_TASKS_H_