/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/

import { QuickPickItem, window, QuickPick } from 'vscode';
import * as nls from 'vscode-nls';
import { RemoteSourceProvider, RemoteSource } from './api/git';
import { Model } from './model';
import { throttle, debounce } from './decorators';

const localize = nls.loadMessageBundle();

async function getQuickPickResult<T extends QuickPickItem>(quickpick: QuickPick<T>): Promise<T | undefined> {
	const result = await new Promise<T | undefined>(c => {
		quickpick.onDidAccept(() => c(quickpick.selectedItems[0]));
		quickpick.onDidHide(() => c(undefined));
		quickpick.show();
	});

	quickpick.hide();
	return result;
}

class RemoteSourceProviderQuickPick {

	private quickpick: QuickPick<QuickPickItem & { remoteSource?: RemoteSource }>;

	constructor(private provider: RemoteSourceProvider) {
		this.quickpick = window.createQuickPick();
		this.quickpick.ignoreFocusOut = true;

		if (provider.supportsQuery) {
			this.quickpick.placeholder = localize('type to search', "Repository name (type to search)");
			this.quickpick.onDidChangeValue(this.onDidChangeValue, this);
		} else {
			this.quickpick.placeholder = localize('type to filter', "Repository name");
		}
	}

	@debounce(300)
	private onDidChangeValue(): void {
		this.query();
	}

	@throttle
	private async query(): Promise<void> {
		this.quickpick.busy = true;

		try {
			const remoteSources = await this.provider.getRemoteSources(this.quickpick.value) || [];

			if (remoteSources.length === 0) {
				this.quickpick.items = [{
					label: localize('none found', "No remote repositories found."),
					alwaysShow: true
				}];
			} else {
				this.quickpick.items = remoteSources.map(remoteSource => ({
					label: remoteSource.name,
					description: remoteSource.description || (typeof remoteSource.url === 'string' ? remoteSource.url : remoteSource.url[0]),
					remoteSource,
					alwaysShow: true
				}));
			}
		} catch (err) {
			this.quickpick.items = [{ label: localize('error', "$(error) Error: {0}", err.message), alwaysShow: true }];
			console.error(err);
		} finally {
			this.quickpick.busy = false;
		}
	}

	async pick(): Promise<RemoteSource | undefined> {
		this.query();
		const result = await getQuickPickResult(this.quickpick);
		return result?.remoteSource;
	}
}

export interface PickRemoteSourceOptions {
	readonly providerLabel?: (provider: RemoteSourceProvider) => string;
	readonly urlLabel?: string;
	readonly providerName?: string;
	readonly branch?: boolean; // then result is PickRemoteSourceResult
}

export interface PickRemoteSourceResult {
	readonly url: string;
	readonly branch?: string;
}

export async function pickRemoteSource(model: Model, options: PickRemoteSourceOptions & { branch?: false | undefined }): Promise<string | undefined>;
export async function pickRemoteSource(model: Model, options: PickRemoteSourceOptions & { branch: true }): Promise<PickRemoteSourceResult | undefined>;
export async function pickRemoteSource(model: Model, options: PickRemoteSourceOptions = {}): Promise<string | PickRemoteSourceResult | undefined> {
	const quickpick = window.createQuickPick<(QuickPickItem & { provider?: RemoteSourceProvider, url?: string })>();
	quickpick.ignoreFocusOut = true;

	if (options.providerName) {
		const provider = model.getRemoteProviders()
			.filter(provider => provider.name === options.providerName)[0];

		if (provider) {
			return await pickProviderSource(provider, options);
		}
	}

	const providers = model.getRemoteProviders()
		.map(provider => ({ label: (provider.icon ? `$(${provider.icon}) ` : '') + (options.providerLabel ? options.providerLabel(provider) : provider.name), alwaysShow: true, provider }));

	quickpick.placeholder = providers.length === 0
		? localize('provide url', "Provide repository URL")
		: localize('provide url or pick', "Provide repository URL or pick a repository source.");

	const updatePicks = (value?: string) => {
		if (value) {
			quickpick.items = [{
				label: options.urlLabel ?? localize('url', "URL"),
				description: value,
				alwaysShow: true,
				url: value
			},
			...providers];
		} else {
			quickpick.items = providers;
		}
	};

	quickpick.onDidChangeValue(updatePicks);
	updatePicks();

	const result = await getQuickPickResult(quickpick);

	if (result) {
		if (result.url) {
			return result.url;
		} else if (result.provider) {
			return await pickProviderSource(result.provider, options);
		}
	}

	return undefined;
}

async function pickProviderSource(provider: RemoteSourceProvider, options: PickRemoteSourceOptions = {}): Promise<string | PickRemoteSourceResult | undefined> {
	const quickpick = new RemoteSourceProviderQuickPick(provider);
	const remote = await quickpick.pick();

	let url: string | undefined;

	if (remote) {
		if (typeof remote.url === 'string') {
			url = remote.url;
		} else if (remote.url.length > 0) {
			url = await window.showQuickPick(remote.url, { ignoreFocusOut: true, placeHolder: localize('pick url', "Choose a URL to clone from.") });
		}
	}

	if (!url || !options.branch) {
		return url;
	}

	if (!provider.getBranches) {
		return { url };
	}

	const branches = await provider.getBranches(url);

	if (!branches) {
		return { url };
	}

	const branch = await window.showQuickPick(branches, {
		placeHolder: localize('branch name', "Branch name")
	});

	if (!branch) {
		return { url };
	}

	return { url, branch };
}