import { Unregisterable } from './shared';
import { EAppUpdateError } from './App';

/**
 * Represents functions related to managing downloads in Steam.
 */
export interface Downloads {
	/**
	 * Enables or disables all downloads in Steam.
	 * @param enable True to enable downloads, false to disable.
	 */
	EnableAllDownloads(enable: boolean): void;

	/**
	 * Moves the update for a specific app down the download queue.
	 * @param appId The ID of the application to move.
	 */
	MoveAppUpdateDown(appId: number): void;

	/**
	 * Moves the update for a specific app up the download queue.
	 * @param appId The ID of the application to move.
	 */
	MoveAppUpdateUp(appId: number): void;

	PauseAppUpdate(appId: number): void; // Broken? It seems to be removing it from download list like RemoveFromDownloadList

	/**
	 * Adds the update for a specific app to the download queue.
	 * @param appId The ID of the application to queue.
	 */
	QueueAppUpdate(appId: number): void;

	/**
	 * Registers a callback function to be called when download items change.
	 * @param callback The callback function to be called.
	 * @returns an object that can be used to unregister the callback.
	 */
	RegisterForDownloadItems(callback: (isDownloading: boolean, downloadItems: DownloadItem[]) => void): Unregisterable;

	/**
	 * Registers a callback function to be called when download overview changes.
	 * @param callback The callback function to be called.
	 * @returns an object that can be used to unregister the callback.
	 */
	RegisterForDownloadOverview(callback: (overview: DownloadOverview) => void): Unregisterable;

	/**
	 * Removes the update for a specific app from the download list and places it in the unscheduled list.
	 * @param appId The ID of the application to remove.
	 */
	RemoveFromDownloadList(appId: number): void;

	/**
	 * Resumes the update for a specific app in the queue.
	 * @param appId The ID of the application to resume.
	 */
	ResumeAppUpdate(appId: number): void;

	/**
	 * Sets an app to launch when its download is complete.
	 * @param appId The ID of the application to set.
	 */
	SetLaunchOnUpdateComplete(appId: number): void;

	/**
	 * Sets the queue index for an app in the download queue.
	 * @param appId The ID of the application to set the index for.
	 * @param index The index to set.
	 * @remarks Index of 0 is the current download in progress.
	 */
	SetQueueIndex(appId: number, index: number): void;

	/**
	 * Suspends or resumes download throttling.
	 * @param suspend Whether to suspend or resume download throttling.
	 */
	SuspendDownloadThrottling(suspend: boolean): void;

	/**
	 * Suspends or resumes local transfers.
	 * @param suspend Whether to suspend or resume local transfers.
	 */
	SuspendLanPeerContent(suspend: boolean): void;
}

export interface DownloadItem {
	/** True if this app is currently downloading */
	active: boolean;
	/** Appid of app */
	appid: number;
	/** Current build ID for the installed app, zero if the app isn't installed yet */
	buildid: number;
	/** True if this update has been completed */
	completed: boolean;
	/** For completed downloads, time of completion, 0 if not completed */
	completed_time: number;
	deferred_time: number;
	/** Bytes already downloaded, sum across all content types */
	downloaded_bytes: number;
	/** If true, game will launch when its download completes successfully */
	launch_on_completion: boolean;
	/** True if this app has been paused by the user or the system */
	paused: boolean;
	/** Queue index, -1 if the item is unqueued */
	queue_index: number;
	/** Build ID that this download is moving towards. This can be the same as buildid.*/
	target_buildid: number;
	/** Total bytes to download, sum across all content types */
	total_bytes: number;
	/**
	 * Update error description, when paused and there has been an error.
	 * Unlocalized and shouldn't be displayed to the user.
	 */
	update_error: string;
	update_result: EAppUpdateError;
	update_type_info: UpdateTypeInfo[];
}

export interface DownloadOverview {
	/** Set if we are downloading from LAN peer content server */
	lan_peer_hostname: string;
	/** True if all downloads are paused */
	paused: boolean;
	/** True if download throttling has been temporarily suspended for the current download */
	throttling_suspended: boolean;
	/** Appid of currently updating app */
	update_appid: number;
	/** Bytes already downloaded */
	update_bytes_downloaded: number;
	/** Bytes already processed in current phase - resets to zero when update stage changes */
	update_bytes_processed: number;
	/** Bytes already staged */
	update_bytes_staged: number;
	/** Total bytes to download */
	update_bytes_to_download: number;
	/** Total bytes to process in current phase - resets to zero when update stage changes */
	update_bytes_to_process: number;
	/** Total bytes to be staged */
	update_bytes_to_stage: number;
	/** Current disk throughput estimate */
	update_disc_bytes_per_second: number;
	/** True if the current update is an initial install */
	update_is_install: boolean;
	/** True if download and staging sizes are prefetch estimates */
	update_is_prefetch_estimate: boolean;
	/** True if the current update is for shader update */
	update_is_shader: boolean;
	/** True if the client is running in peer content server mode serving other peers */
	update_is_upload: boolean;
	/** True if the current update is for workshop content */
	update_is_workshop: boolean;
	/** Current bandwidth estimate for download */
	update_network_bytes_per_second: number;
	/** Peak bandwidth estimate for download */
	update_peak_network_bytes_per_second: number;
	/** Estimate of remaining time (in seconds) until download completes (not including staging) */
	update_seconds_remaining: number;
	/** Time current update started */
	update_start_time: number;
	update_state: 'None' | 'Starting' | 'Updating' | 'Stopping';
}

export interface UpdateTypeInfo {
	/** True if this content type had an update and it has completed */
	completed_update: boolean;
	/** Bytes already downloaded for this content type */
	downloaded_bytes: number;
	/** True if this content type has or had an update */
	has_update: boolean;
	/** Total bytes to download for this content type */
	total_bytes: number;
}