/* 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/. */

#include "nsIRequest.idl"

interface nsIRequest;
interface nsIRequestObserver;

interface nsIBitsRequest;

interface nsIBitsNewRequestCallback;
interface nsIBitsCallback;

typedef long nsProxyUsage;
typedef long nsBitsErrorType;
typedef long nsBitsErrorAction;
typedef long nsBitsErrorStage;

/**
 * An interface for interacting with Windows Background Intelligent Transfer
 * Service. This should only be used on Windows.
 *
 * It would be preferable for the functions in this interface to return
 * Promises, but this interface is implemented in Rust, which does not yet have
 * support for Promises. There is a JS wrapper around this class that should be
 * preferred over using this interface directly, located in Bits.sys.mjs.
 *
 * Methods of this class that take a nsIBitsNewRequestCallback do not return or
 * throw errors. All errors will be reported through the callback. The only
 * things that should cause methods to directly throw errors are null arguments.
 */
[scriptable, uuid(495d6f3d-9748-4d30-8ce5-0290c0001edf)]
interface nsIBits : nsISupports
{
  /**
   * nsBitsErrorType values
   * The BITS interface returns many error codes. These are intended to help
   * determine appropriate fallback actions and to report to telemetry.
   */
  const long ERROR_TYPE_SUCCESS                                           = 0;
  const long ERROR_TYPE_UNKNOWN                                           = 1;
  const long ERROR_TYPE_METHOD_THREW                                      = 2;
  const long ERROR_TYPE_METHOD_TIMEOUT                                    = 3;
  const long ERROR_TYPE_NULL_ARGUMENT                                     = 4;
  const long ERROR_TYPE_INVALID_ARGUMENT                                  = 5;
  const long ERROR_TYPE_NOT_INITIALIZED                                   = 6;
  const long ERROR_TYPE_NO_UTF8_CONVERSION                                = 7;
  const long ERROR_TYPE_INVALID_GUID                                      = 8;
  const long ERROR_TYPE_PIPE_NOT_CONNECTED                                = 9;
  const long ERROR_TYPE_PIPE_TIMEOUT                                      = 10;
  const long ERROR_TYPE_PIPE_BAD_WRITE_COUNT                              = 11;
  const long ERROR_TYPE_PIPE_API_ERROR                                    = 12;
  const long ERROR_TYPE_FAILED_TO_CREATE_BITS_JOB                         = 13;
  const long ERROR_TYPE_FAILED_TO_ADD_FILE_TO_JOB                         = 14;
  const long ERROR_TYPE_FAILED_TO_APPLY_BITS_JOB_SETTINGS                 = 15;
  const long ERROR_TYPE_FAILED_TO_RESUME_BITS_JOB                         = 16;
  const long ERROR_TYPE_OTHER_BITS_ERROR                                  = 17;
  const long ERROR_TYPE_OTHER_BITS_CLIENT_ERROR                           = 18;
  const long ERROR_TYPE_BITS_JOB_NOT_FOUND                                = 19;
  const long ERROR_TYPE_FAILED_TO_GET_BITS_JOB                            = 20;
  const long ERROR_TYPE_FAILED_TO_SUSPEND_BITS_JOB                        = 21;
  const long ERROR_TYPE_FAILED_TO_COMPLETE_BITS_JOB                       = 22;
  const long ERROR_TYPE_PARTIALLY_COMPLETED_BITS_JOB                      = 23;
  const long ERROR_TYPE_FAILED_TO_CANCEL_BITS_JOB                         = 24;
  const long ERROR_TYPE_MISSING_RESULT_DATA                               = 25;
  const long ERROR_TYPE_MISSING_CALLBACK                                  = 26;
  const long ERROR_TYPE_CALLBACK_ON_WRONG_THREAD                          = 27;
  const long ERROR_TYPE_MISSING_BITS_SERVICE                              = 28;
  const long ERROR_TYPE_BITS_SERVICE_ON_WRONG_THREAD                      = 29;
  const long ERROR_TYPE_MISSING_BITS_REQUEST                              = 30;
  const long ERROR_TYPE_BITS_REQUEST_ON_WRONG_THREAD                      = 31;
  const long ERROR_TYPE_MISSING_OBSERVER                                  = 32;
  const long ERROR_TYPE_OBSERVER_ON_WRONG_THREAD                          = 33;
  const long ERROR_TYPE_MISSING_CONTEXT                                   = 34;
  const long ERROR_TYPE_CONTEXT_ON_WRONG_THREAD                           = 35;
  const long ERROR_TYPE_FAILED_TO_START_THREAD                            = 36;
  const long ERROR_TYPE_FAILED_TO_CONSTRUCT_TASK_RUNNABLE                 = 37;
  const long ERROR_TYPE_FAILED_TO_DISPATCH_RUNNABLE                       = 38;
  const long ERROR_TYPE_TRANSFER_ALREADY_COMPLETE                         = 39;
  const long ERROR_TYPE_OPERATION_ALREADY_IN_PROGRESS                     = 40;
  const long ERROR_TYPE_MISSING_BITS_CLIENT                               = 41;
  const long ERROR_TYPE_FAILED_TO_GET_JOB_STATUS                          = 42;
  const long ERROR_TYPE_BITS_STATE_ERROR                                  = 43;
  const long ERROR_TYPE_BITS_STATE_TRANSIENT_ERROR                        = 44;
  const long ERROR_TYPE_BITS_STATE_CANCELLED                              = 45;
  const long ERROR_TYPE_BITS_STATE_UNEXPECTED                             = 46;
  const long ERROR_TYPE_VERIFICATION_FAILURE                              = 47;
  const long ERROR_TYPE_ACCESS_DENIED_EXPECTED                            = 48;
  const long ERROR_TYPE_FAILED_TO_CONNECT_TO_BCM                          = 49;
  const long ERROR_TYPE_USE_AFTER_REQUEST_SHUTDOWN                        = 50;
  const long ERROR_TYPE_BROWSER_SHUTTING_DOWN                             = 51;
  /**
   * nsBitsErrorAction values
   * These values indicate where the error occurred.
   */
  const long ERROR_ACTION_UNKNOWN                                         = 1;
  const long ERROR_ACTION_NONE                                            = 2;
  const long ERROR_ACTION_START_DOWNLOAD                                  = 3;
  const long ERROR_ACTION_MONITOR_DOWNLOAD                                = 4;
  const long ERROR_ACTION_CHANGE_MONITOR_INTERVAL                         = 5;
  const long ERROR_ACTION_CANCEL                                          = 6;
  const long ERROR_ACTION_SET_PRIORITY                                    = 7;
  const long ERROR_ACTION_COMPLETE                                        = 8;
  const long ERROR_ACTION_SUSPEND                                         = 9;
  const long ERROR_ACTION_RESUME                                          = 10;
  const long ERROR_ACTION_SET_NO_PROGRESS_TIMEOUT                         = 11;

  /**
   * nsBitsErrorStage values
   * These values allow the caller to determine at what point in the download
   * mechanism a failure occurred.
   */
  const long ERROR_STAGE_UNKNOWN                                          = 1;
  const long ERROR_STAGE_PRETASK                                          = 2;
  const long ERROR_STAGE_COMMAND_THREAD                                   = 3;
  const long ERROR_STAGE_AGENT_COMMUNICATION                              = 4;
  const long ERROR_STAGE_BITS_CLIENT                                      = 5;
  const long ERROR_STAGE_MAIN_THREAD                                      = 6;
  const long ERROR_STAGE_MONITOR                                          = 7;
  const long ERROR_STAGE_VERIFICATION                                     = 8;

  /**
   * These values indicate what type of error code was returned. These are used
   * to allow the different types taken by the different callback failure
   * functions to be made into one generic error type in Javascript.
   */
  const long ERROR_CODE_TYPE_NONE                                         = 1;
  const long ERROR_CODE_TYPE_NSRESULT                                     = 2;
  const long ERROR_CODE_TYPE_HRESULT                                      = 3;
  const long ERROR_CODE_TYPE_STRING                                       = 4;
  const long ERROR_CODE_TYPE_EXCEPTION                                    = 5;

  /**
   * Indicates whether init() has been called.
   */
  readonly attribute boolean initialized;

  /**
   * Initializes the BITS interface. Unlike other functions here, this happens
   * synchronously.
   * init() should only be called only once.
   *
   * @param jobName
   *        The name of the BITS job. This is used both to set the name during
   *        job creation and to verify that a job is ours.
   * @param savePathPrefix
   *        The directory that downloads will be saved to. Providing a safe
   *        directory here ensures that the download path cannot be manipulated
   *        to save files to a malicious location. Downloads are guaranteed to
   *        be saved to this directory or a subdirectory.
   * @param monitorTimeoutMs
   *        The amount of time to wait between download monitor notifications.
   *        This should be larger than the largest monitorIntervalMs that will
   *        be passed to startDownload(), monitorDownload(), or
   *        changeMonitorInterval(). This value may not be 0.
   */
  void init(in AUTF8String jobName,
            in AUTF8String savePathPrefix,
            in unsigned long monitorTimeoutMs);

  /**
   * Downloads the specified URL to the specified location within the
   * savePathPrefix passed to init().
   *
   * @param downloadURL
   *        The URL to be downloaded.
   * @param saveRelativePath
   *        The location to download to. The path given should be a path
   *        relative to the savePathPrefix passed to init(). If this attempts to
   *        escape the directory specified by savePathPrefix, this call will
   *        fail (ex: Don't pass "../filename").
   * @param proxy
   *        Specifies what proxy to use when downloading. Valid values are
   *        listed below.
   * @param noProgressTimeoutSecs
   *        The number of seconds for the "no progress" timeout. After there has
   *        been no download progress for this long, BITS will not retry the job
   *        following a transient error, producing instead a permanent error.
   * @param monitorIntervalMs
   *        The number of milliseconds between download status notifications.
   * @param customHeaders
   *        Custom headers to append to the HTTP request. Each header must be
   *        terminated by a carriage return and line feed (CR/LF) character. The
   *        string is limited to 16,384 characters, including any null
   *        terminator.
   * @param observer
   *        An observer to be notified of various events. OnStartRequest is
   *        called once the BITS job has been created. OnStopRequest is called
   *        when the file transfer has completed or when an error occurs. If
   *        this object implements nsIProgressEventSink, then its OnProgress
   *        method will be called as data is transferred.
   *        IMPORTANT NOTE: When OnStopRequest is called, the download has
   *                        completed, but nsIBitsRequest::complete() still
   *                        needs to be called to save the file to the
   *                        filesystem.
   * @param context
   *        User defined object forwarded to the observer's onProgress method.
   *        This parameter, unlike others for this interface, can be passed a
   *        null pointer.
   * @param callback
   *        The callback used to relay the response from BITS.
   */
  void startDownload(in AUTF8String downloadURL,
                     in AUTF8String saveRelativePath,
                     in nsProxyUsage proxy,
                     in unsigned long noProgressTimeoutSecs,
                     in unsigned long monitorIntervalMs,
                     in AUTF8String customHeaders,
                     in nsIRequestObserver observer,
                     in nsISupports context,
                     in nsIBitsNewRequestCallback callback);

  // nsProxyUsage values
  const long PROXY_NONE = 1;
  const long PROXY_PRECONFIG = 2;
  const long PROXY_AUTODETECT = 3;

  /**
   * Similar to startDownload, but connects to a BITS transfer that has already
   * been started.
   *
   * @param id
   *        The GUID of the download to monitor.
   * @param monitorIntervalMs
   *        The number of milliseconds between download status notifications.
   * @param observer
   *        An observer to be notified of various events. OnStartRequest is
   *        called once the BITS job has been created. OnStopRequest is called
   *        when the file transfer has completed or when an error occurs. If
   *        this object implements nsIProgressEventSink, then its OnProgress
   *        method will be called as data is transferred.
   *        IMPORTANT NOTE: When OnStopRequest is called, the download has
   *                        completed, but nsIBitsRequest::complete() still
   *                        needs to be called to save the file to the
   *                        filesystem.
   * @param context
   *        User defined object forwarded to the observer's onProgress method.
   *        This parameter, unlike others for this interface, can be passed a
   *        null pointer.
   * @param callback
   *        The callback used to relay the response from BITS.
   */
  void monitorDownload(in AUTF8String id,
                       in unsigned long monitorIntervalMs,
                       in nsIRequestObserver observer,
                       in nsISupports context,
                       in nsIBitsNewRequestCallback callback);
};

/**
 * This callback interface is for use by the nsIBits interface for returning
 * results asynchronously to the caller.
 */
[scriptable, uuid(aa12e433-5b9f-452d-b5c9-840a9541328b)]
interface nsIBitsNewRequestCallback : nsISupports
{
  void success(in nsIBitsRequest request);
  void failure(in nsBitsErrorType errorType,
               in nsBitsErrorAction errorAction,
               in nsBitsErrorStage errorStage);
  void failureNsresult(in nsBitsErrorType errorType,
                       in nsBitsErrorAction errorAction,
                       in nsBitsErrorStage errorStage,
                       in nsresult errorCode);
  void failureHresult(in nsBitsErrorType errorType,
                      in nsBitsErrorAction errorAction,
                      in nsBitsErrorStage errorStage,
                      in long errorCode);
  void failureString(in nsBitsErrorType errorType,
                     in nsBitsErrorAction errorAction,
                     in nsBitsErrorStage errorStage,
                     in AUTF8String errorMessage);
};

/*
 * An interface for managing a running BITS download.
 *
 * It would be preferable for the functions in this interface to return
 * Promises, but this interface is implemented in Rust, which does not yet have
 * support for Promises. There is a JS wrapper around this class that should be
 * preferred over using this interface directly, located in Bits.sys.mjs.
 *
 * Methods of this class that take a nsIBitsCallback do not return or throw
 * errors. All errors will be reported through the callback. The only
 * things that should cause methods to directly throw errors are null arguments.
 *
 * Note: Although the nsIBits interface derives from nsIRequest, implementations
 *       may not implement the loadGroup or loadFlags attributes.
 *
 * Note: Once the file transfer has stopped (due to completion or error),
 *       calling any method besides complete() or cancel() will result in an
 *       error with type nsIBits::ERROR_TYPE_TRANSFER_ALREADY_COMPLETE.
 *       Calling complete() or cancel() again after either has already been
 *       called will also result in an ERROR_TYPE_TRANSFER_ALREADY_COMPLETE
 *       error.
 *       Attributes and nsIRequest::isPending() can still be accessed at any
 *       time.
 */
[scriptable, uuid(ab9da0e9-06bf-4e73-bb1b-c0f2ea9ecc3e)]
interface nsIBitsRequest : nsIRequest
{
  /**
   * The BITS id of the download. This will be a string representing a UUID.
   */
  readonly attribute AUTF8String bitsId;

  /**
   * The transfer result of the download, meant to be accessed after the
   * transfer has stopped (i.e. after the observer's onStopRequest method has
   * been called). Will be nsIBits::ERROR_TYPE_SUCCESS if the transfer is
   * successful (and before transfer completion). If the transfer failed, this
   * will be a different nsBitsErrorType value indicating the cause of the
   * failure.
   */
  readonly attribute nsBitsErrorType transferError;

  /**
   * HRESULT error code reported by BITS for the transfer failure, if available.
   * This will be 0 if there was no error or if the failure is not associated
   * with an HRESULT. Intended to be read after the transfer has stopped,
   * alongside transferError.
   */
  readonly attribute long transferErrorCode;

  /**
   * Requests a change to the frequency that Firefox is receiving download
   * status notifications.
   *
   * @param monitorIntervalMs
   *        The new number of milliseconds between download status
   *        notifications.
   * @param callback
   *        The callback function used to relay success or failure.
   */
  void changeMonitorInterval(in unsigned long monitorIntervalMs,
                             in nsIBitsCallback callback);

  /**
   * Cancels the download. This function is named this way to avoid conflict
   * with nsIRequest::cancel.
   *
   * @param status
   *        The reason for cancelling the request. This must be a failure code
   *        rather than a success code like NS_OK.
   * @param callback
   *        The callback function used to relay success or failure.
   */
  void cancelAsync(in nsresult status,
                   in nsIBitsCallback callback);

  /**
   * Sets the priority of the BITS job to high (i.e. foreground download).
   *
   * @param callback
   *        The callback function used to relay success or failure.
   */
  void setPriorityHigh(in nsIBitsCallback callback);

  /**
   * Sets the priority of the BITS job to low (i.e. background download).
   *
   * @param callback
   *        The callback function used to relay success or failure.
   */
  void setPriorityLow(in nsIBitsCallback callback);

  /**
   * Sets the BITS "no progress" timeout for the job.
   *
   * @param timeoutSecs
   *        The new number of seconds for the timeout. After there has been
   *        no progress for this long, BITS will not retry the job following
   *        a transient error, producing instead a permanent error.
   * @param callback
   *        The callback function used to relay success or failure.
   */
  void setNoProgressTimeout(in unsigned long timeoutSecs,
                             in nsIBitsCallback callback);

  /*
   * Completes the download, moving it out of the BITS system and onto the
   * disk location specified when startDownload was called.
   *
   * @param callback
   *        The callback function used to relay success or failure.
   */
  void complete(in nsIBitsCallback callback);

  /*
   * Suspends the download, preventing more data from being transferred until
   * the download is resumed. This function is named this way to avoid conflict
   * with nsIRequest::suspend.
   *
   * @param callback
   *        The callback function used to relay success or failure.
   */
  void suspendAsync(in nsIBitsCallback callback);

  /*
   * Resumes a previously suspended download. This function is named this way
   * to avoid conflict with nsIRequest::resume.
   *
   * @param callback
   *        The callback function used to relay success or failure.
   */
  void resumeAsync(in nsIBitsCallback callback);
};

/**
 * This callback interface is for use by the nsIBitsRequest interface for
 * returning results asynchronously to the caller.
 */
[scriptable, uuid(ea657e66-6bad-4e41-84d9-c6d107e9799d)]
interface nsIBitsCallback : nsISupports
{
  void success();
  void failure(in nsBitsErrorType errorType,
               in nsBitsErrorAction errorAction,
               in nsBitsErrorStage errorStage);
  void failureNsresult(in nsBitsErrorType errorType,
                       in nsBitsErrorAction errorAction,
                       in nsBitsErrorStage errorStage,
                       in nsresult errorCode);
  void failureHresult(in nsBitsErrorType errorType,
                      in nsBitsErrorAction errorAction,
                      in nsBitsErrorStage errorStage,
                      in long errorCode);
  void failureString(in nsBitsErrorType errorType,
                     in nsBitsErrorAction errorAction,
                     in nsBitsErrorStage errorStage,
                     in AUTF8String errorMessage);
};
