/**
 *  Copyright 2023 Continue Dev, Inc.
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
import { CancellationToken } from 'vscode';

import { ILanguageServiceProvider } from 'base/common/languages/languageService';

import { VSCodeAction } from '../../editor/editor-api/VSCodeAction';
import { ChunkerManager } from '../chunk/ChunkerManager';
import { SqliteDb } from '../database/SqliteDb';
import { getComputeDeleteAddRemove } from '../refreshIndex';
import { CodebaseIndex, IndexingProgressUpdate, IndexTag } from './_base/CodebaseIndex';
import { ChunkCodebaseIndex } from './ChunkCodebaseIndex';
import { CodeSnippetsCodebaseIndex } from './CodeSnippetsCodebaseIndex';
import { FullTextSearchCodebaseIndex } from './FullTextSearchCodebaseIndex';
import { GlobalCacheCodeBaseIndex } from './GlobalCacheCodeBaseIndex';
import { LanceDbIndex } from './LanceDbIndex';

export class CodebaseIndexer {
	constructor(
		private ide: VSCodeAction,
		private db: LanceDbIndex,
		private lsp: ILanguageServiceProvider,
		private chunkerManager: ChunkerManager,
	) {}

	private getIndexesToBuild(): CodebaseIndex[] {
		return [
			new CodeSnippetsCodebaseIndex(this.ide, this.lsp),
			new ChunkCodebaseIndex(this.lsp, this.ide.readFile.bind(this.ide), this.chunkerManager),
			new FullTextSearchCodebaseIndex(),
			this.db,
		];
	}

	async *refresh(workspaceDirs: string[], token: CancellationToken): AsyncGenerator<IndexingProgressUpdate> {
		const db = await SqliteDb.get();

		const globalCacheIndex = new GlobalCacheCodeBaseIndex(db);
		const indexesToBuild = this.getIndexesToBuild();

		let completedDirs = 0;

		// Wait until Git Extension has loaded to report progress
		// so we don't appear stuck at 0% while waiting
		if (workspaceDirs.length > 0) {
			let repoName = await this.ide.getRepoName(workspaceDirs[0]);
			if (!repoName) {
				console.error('Repo name not found');
			}
		}

		yield {
			progress: 0,
			desc: 'Starting indexing...',
		};

		for (let directory of workspaceDirs) {
			const stats = await this.ide.getStats(directory);
			const branch = await this.ide.getBranch(directory);
			const repoName = await this.ide.getRepoName(directory);
			let completedIndexes = 0;

			try {
				for (let codebaseIndex of indexesToBuild) {
					const tag: IndexTag = {
						directory,
						branch,
						artifactId: codebaseIndex.artifactId,
					};
					const [results, markComplete] = await getComputeDeleteAddRemove(
						globalCacheIndex,
						tag,
						{ ...stats },
						filepath => this.ide.readFile(filepath),
						repoName,
					);

					for await (let { progress, desc } of codebaseIndex.update(tag, results, markComplete, repoName)) {
						// Handle pausing in this loop because it's the only one really taking time
						if (token.isCancellationRequested) {
							yield {
								progress: 1,
								desc: 'Indexing cancelled',
							};
							return;
						}

						// while (this.pauseToken.paused) {
						// 	await new Promise((resolve) => setTimeout(resolve, 100));
						// }

						yield {
							progress: (completedDirs + (completedIndexes + progress) / indexesToBuild.length) / workspaceDirs.length,
							desc,
						};
					}
					completedIndexes++;
					yield {
						progress: (completedDirs + completedIndexes / indexesToBuild.length) / workspaceDirs.length,
						desc: 'Completed indexing ' + codebaseIndex.artifactId,
					};
				}
			} catch (e) {
				console.warn('Error refreshing index: ', e);
			}

			completedDirs++;

			yield {
				progress: completedDirs / workspaceDirs.length,
				desc: 'Indexing Complete',
			};
		}
	}
}