'use strict';
import {
	CancellationToken,
	commands,
	ConfigurationChangeEvent,
	ProgressLocation,
	TreeItem,
	TreeItemCollapsibleState,
	window,
} from 'vscode';
import { configuration, StashesViewConfig, ViewFilesLayout } from '../configuration';
import { Container } from '../container';
import { GitReference, GitStashReference, Repository, RepositoryChange, RepositoryChangeEvent } from '../git/git';
import { GitUri } from '../git/gitUri';
import {
	ContextValues,
	MessageNode,
	RepositoryNode,
	StashesNode,
	StashNode,
	SubscribeableViewNode,
	unknownGitUri,
	ViewNode,
} from './nodes';
import { debug, gate } from '../system';
import { ViewBase } from './viewBase';

export class StashesRepositoryNode extends SubscribeableViewNode<StashesView> {
	protected splatted = true;
	private child: StashesNode | undefined;

	constructor(uri: GitUri, view: StashesView, parent: ViewNode, public readonly repo: Repository, splatted: boolean) {
		super(uri, view, parent);

		this.splatted = splatted;
	}

	get id(): string {
		return RepositoryNode.getId(this.repo.path);
	}

	async getChildren(): Promise<ViewNode[]> {
		if (this.child == null) {
			this.child = new StashesNode(this.uri, this.view, this, this.repo);
		}

		return this.child.getChildren();
	}

	getTreeItem(): TreeItem {
		this.splatted = false;

		const item = new TreeItem(
			this.repo.formattedName ?? this.uri.repoPath ?? '',
			TreeItemCollapsibleState.Expanded,
		);
		item.contextValue = ContextValues.RepositoryFolder;

		return item;
	}

	async getSplattedChild() {
		if (this.child == null) {
			await this.getChildren();
		}

		return this.child;
	}

	@gate()
	@debug()
	async refresh(reset: boolean = false) {
		await this.child?.triggerChange(reset);

		await this.ensureSubscription();
	}

	@debug()
	protected subscribe() {
		return this.repo.onDidChange(this.onRepositoryChanged, this);
	}

	@debug({
		args: {
			0: (e: RepositoryChangeEvent) =>
				`{ repository: ${e.repository?.name ?? ''}, changes: ${e.changes.join()} }`,
		},
	})
	private onRepositoryChanged(e: RepositoryChangeEvent) {
		if (e.changed(RepositoryChange.Closed)) {
			this.dispose();
			void this.parent?.triggerChange(true);

			return;
		}

		if (e.changed(RepositoryChange.Config) || e.changed(RepositoryChange.Stash)) {
			void this.triggerChange(true);
		}
	}
}

export class StashesViewNode extends ViewNode<StashesView> {
	protected splatted = true;
	private children: StashesRepositoryNode[] | undefined;

	constructor(view: StashesView) {
		super(unknownGitUri, view);
	}

	async getChildren(): Promise<ViewNode[]> {
		if (this.children == null) {
			const repositories = await Container.git.getOrderedRepositories();
			if (repositories.length === 0) return [new MessageNode(this.view, this, 'No stashes could be found.')];

			const splat = repositories.length === 1;
			this.children = repositories.map(
				r => new StashesRepositoryNode(GitUri.fromRepoPath(r.path), this.view, this, r, splat),
			);
		}

		if (this.children.length === 1) {
			const [child] = this.children;

			const stash = await child.repo.getStash();
			this.view.title = `Stashes (${stash?.commits.size ?? 0})`;

			return child.getChildren();
		}

		return this.children;
	}

	getTreeItem(): TreeItem {
		const item = new TreeItem('Stashes', TreeItemCollapsibleState.Expanded);
		return item;
	}

	async getSplattedChild() {
		if (this.children == null) {
			await this.getChildren();
		}

		return this.children?.length === 1 ? this.children[0] : undefined;
	}

	@gate()
	@debug()
	refresh(reset: boolean = false) {
		if (reset && this.children != null) {
			for (const child of this.children) {
				child.dispose();
			}
			this.children = undefined;
		}
	}
}

export class StashesView extends ViewBase<StashesViewNode, StashesViewConfig> {
	protected readonly configKey = 'stashes';

	constructor() {
		super('gitlens.views.stashes', 'Stashes');
	}

	getRoot() {
		return new StashesViewNode(this);
	}

	protected registerCommands() {
		void Container.viewCommands;

		commands.registerCommand(
			this.getQualifiedCommand('copy'),
			() => commands.executeCommand('gitlens.views.copy', this.selection),
			this,
		);
		commands.registerCommand(this.getQualifiedCommand('refresh'), () => this.refresh(true), this);
		commands.registerCommand(
			this.getQualifiedCommand('setFilesLayoutToAuto'),
			() => this.setFilesLayout(ViewFilesLayout.Auto),
			this,
		);
		commands.registerCommand(
			this.getQualifiedCommand('setFilesLayoutToList'),
			() => this.setFilesLayout(ViewFilesLayout.List),
			this,
		);
		commands.registerCommand(
			this.getQualifiedCommand('setFilesLayoutToTree'),
			() => this.setFilesLayout(ViewFilesLayout.Tree),
			this,
		);
	}

	protected filterConfigurationChanged(e: ConfigurationChangeEvent) {
		const changed = super.filterConfigurationChanged(e);
		if (
			!changed &&
			!configuration.changed(e, 'defaultDateFormat') &&
			!configuration.changed(e, 'defaultDateSource') &&
			!configuration.changed(e, 'defaultDateStyle') &&
			!configuration.changed(e, 'defaultGravatarsStyle')
		) {
			return false;
		}

		return true;
	}

	findStash(stash: GitStashReference, token?: CancellationToken) {
		const repoNodeId = RepositoryNode.getId(stash.repoPath);

		return this.findNode(StashNode.getId(stash.repoPath, stash.ref), {
			maxDepth: 2,
			canTraverse: n => {
				if (n instanceof StashesViewNode) return true;

				if (n instanceof StashesRepositoryNode) {
					return n.id.startsWith(repoNodeId);
				}

				return false;
			},
			token: token,
		});
	}

	@gate(() => '')
	async revealStash(
		stash: GitStashReference,
		options?: {
			select?: boolean;
			focus?: boolean;
			expand?: boolean | number;
		},
	) {
		return window.withProgress(
			{
				location: ProgressLocation.Notification,
				title: `Revealing ${GitReference.toString(stash, { icon: false })} in the side bar...`,
				cancellable: true,
			},
			async (progress, token) => {
				const node = await this.findStash(stash, token);
				if (node == null) return undefined;

				await this.ensureRevealNode(node, options);

				return node;
			},
		);
	}

	private setFilesLayout(layout: ViewFilesLayout) {
		return configuration.updateEffective('views', this.configKey, 'files', 'layout', layout);
	}
}