// Copyright (c) Microsoft Corporation. All rights reserved.

// Licensed under the MIT License.

'use strict';

import { inject, injectable } from 'inversify';

import { Minimatch } from 'minimatch';

import * as path from 'path';

import * as vscode from 'vscode';

import { IDocumentManager, IWorkspaceService } from '../common/application/types';

import { STANDARD_OUTPUT_CHANNEL } from '../common/constants';

import { IFileSystem } from '../common/platform/types';

import { IConfigurationService, IOutputChannel } from '../common/types';

import { isNotebookCell } from '../common/utils/misc';

import { StopWatch } from '../common/utils/stopWatch';

import { IServiceContainer } from '../ioc/types';

import { sendTelemetryWhenDone } from '../telemetry';

import { EventName } from '../telemetry/constants';

import { LinterTrigger, LintingTelemetry } from '../telemetry/types';

import { ILinterInfo, ILinterManager, ILintingEngine, ILintMessage, LintMessageSeverity } from './types';

const PYTHON: vscode.DocumentFilter = { language: 'python' };

const lintSeverityToVSSeverity = new Map<LintMessageSeverity, vscode.DiagnosticSeverity>();

lintSeverityToVSSeverity.set(LintMessageSeverity.Error, vscode.DiagnosticSeverity.Error);

lintSeverityToVSSeverity.set(LintMessageSeverity.Hint, vscode.DiagnosticSeverity.Hint);

lintSeverityToVSSeverity.set(LintMessageSeverity.Information, vscode.DiagnosticSeverity.Information);

lintSeverityToVSSeverity.set(LintMessageSeverity.Warning, vscode.DiagnosticSeverity.Warning);

@injectable()

export class LintingEngine implements ILintingEngine {

private workspace: IWorkspaceService;

private documents: IDocumentManager;

private configurationService: IConfigurationService;

private linterManager: ILinterManager;

private diagnosticCollection: vscode.DiagnosticCollection;

private pendingLintings = new Map<string, vscode.CancellationTokenSource>();

private outputChannel: vscode.OutputChannel;

private fileSystem: IFileSystem;

constructor(@inject(IServiceContainer) private serviceContainer: IServiceContainer) {

this.documents = serviceContainer.get<IDocumentManager>(IDocumentManager);

this.workspace = serviceContainer.get<IWorkspaceService>(IWorkspaceService);

this.configurationService = serviceContainer.get<IConfigurationService>(IConfigurationService);

this.outputChannel = serviceContainer.get<vscode.OutputChannel>(IOutputChannel, STANDARD_OUTPUT_CHANNEL);

this.linterManager = serviceContainer.get<ILinterManager>(ILinterManager);

this.fileSystem = serviceContainer.get<IFileSystem>(IFileSystem);

this.diagnosticCollection = vscode.languages.createDiagnosticCollection('python');

}

public get diagnostics(): vscode.DiagnosticCollection {

return this.diagnosticCollection;

}

public clearDiagnostics(document: vscode.TextDocument): void {

if (this.diagnosticCollection.has(document.uri)) {

this.diagnosticCollection.delete(document.uri);

}

}

public async lintOpenPythonFiles(): Promise<vscode.DiagnosticCollection> {

this.diagnosticCollection.clear();

const promises = this.documents.textDocuments.map(async (document) => this.lintDocument(document, 'auto'));

await Promise.all(promises);

return this.diagnosticCollection;

}

public async lintDocument(document: vscode.TextDocument, trigger: LinterTrigger): Promise<void> {

if (isNotebookCell(document)) {

return;

}

this.diagnosticCollection.set(document.uri, []);

// Check if we need to lint this document

if (!(await this.shouldLintDocument(document))) {

return;

}

if (this.pendingLintings.has(document.uri.fsPath)) {

this.pendingLintings.get(document.uri.fsPath)!.cancel();

this.pendingLintings.delete(document.uri.fsPath);

}

const cancelToken = new vscode.CancellationTokenSource();

cancelToken.token.onCancellationRequested(() => {

if (this.pendingLintings.has(document.uri.fsPath)) {

this.pendingLintings.delete(document.uri.fsPath);

}

});

this.pendingLintings.set(document.uri.fsPath, cancelToken);

const activeLinters = await this.linterManager.getActiveLinters(document.uri);

const promises: Promise<ILintMessage[]>[] = activeLinters.map(async (info: ILinterInfo) => {

const stopWatch = new StopWatch();

const linter = await this.linterManager.createLinter(

info.product,

this.outputChannel,

this.serviceContainer,

document.uri,

);

const promise = linter.lint(document, cancelToken.token);

this.sendLinterRunTelemetry(info, document.uri, promise, stopWatch, trigger);

return promise;

});

// linters will resolve asynchronously - keep a track of all

// diagnostics reported as them come in.

let diagnostics: vscode.Diagnostic[] = [];

const settings = this.configurationService.getSettings(document.uri);

for (const p of promises) {

const msgs = await p;

if (cancelToken.token.isCancellationRequested) {

break;

}

if (this.isDocumentOpen(document.uri)) {

// Build the message and suffix the message with the name of the linter used.

for (const m of msgs) {

diagnostics.push(this.createDiagnostics(m, document));

}

// Limit the number of messages to the max value.

diagnostics = diagnostics.filter((_value, index) => index <= settings.linting.maxNumberOfProblems);

}

}

// Set all diagnostics found in this pass, as this method always clears existing diagnostics.

this.diagnosticCollection.set(document.uri, diagnostics);

}

private sendLinterRunTelemetry(

info: ILinterInfo,

resource: vscode.Uri,

promise: Promise<ILintMessage[]>,

stopWatch: StopWatch,

trigger: LinterTrigger,

): void {

const linterExecutablePathName = info.pathName(resource);

const properties: LintingTelemetry = {

tool: info.id,

hasCustomArgs: info.linterArgs(resource).length > 0,

trigger,

executableSpecified: linterExecutablePathName.length > 0,

};

sendTelemetryWhenDone(EventName.LINTING, promise, stopWatch, properties);

}

private isDocumentOpen(uri: vscode.Uri): boolean {

return this.documents.textDocuments.some((document) => document.uri.fsPath === uri.fsPath);

}

private createDiagnostics(message: ILintMessage, _document: vscode.TextDocument): vscode.Diagnostic {

const position = new vscode.Position(message.line - 1, message.column);

const range = new vscode.Range(position, position);

const severity = lintSeverityToVSSeverity.get(message.severity!)!;

const diagnostic = new vscode.Diagnostic(range, message.message, severity);

diagnostic.code = message.code;

diagnostic.source = message.provider;

return diagnostic;

}

private async shouldLintDocument(document: vscode.TextDocument): Promise<boolean> {

if (!(await this.linterManager.isLintingEnabled(document.uri))) {

this.diagnosticCollection.set(document.uri, []);

return false;

}

if (document.languageId !== PYTHON.language) {

return false;

}

const workspaceFolder = this.workspace.getWorkspaceFolder(document.uri);

const workspaceRootPath =

workspaceFolder && typeof workspaceFolder.uri.fsPath === 'string' ? workspaceFolder.uri.fsPath : undefined;

const relativeFileName =

typeof workspaceRootPath === 'string'

? path.relative(workspaceRootPath, document.fileName)

: document.fileName;

const settings = this.configurationService.getSettings(document.uri);

// { dot: true } is important so dirs like `.venv` will be matched by globs

const ignoreMinmatches = settings.linting.ignorePatterns.map(

(pattern) => new Minimatch(pattern, { dot: true }),

);

if (ignoreMinmatches.some((matcher) => matcher.match(document.fileName) || matcher.match(relativeFileName))) {

return false;

}

if (document.uri.scheme !== 'file' || !document.uri.fsPath) {

return false;

}

return this.fileSystem.fileExists(document.uri.fsPath);

}

}