import * as os from 'os';

import * as vscode from 'vscode';

import { IProcessService, IPythonExecutionFactory } from './common/process/types';

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

import * as sortProvider from './providers/importSortProvider';

export function activate(context: vscode.ExtensionContext, outChannel: vscode.OutputChannel, serviceContainer: IServiceContainer) {

const rootDir = context.asAbsolutePath('.');

const disposable = vscode.commands.registerCommand('python.sortImports', () => {

const activeEditor = vscode.window.activeTextEditor;

if (!activeEditor || activeEditor.document.languageId !== 'python') {

vscode.window.showErrorMessage('Please open a Python source file to sort the imports.');

return Promise.resolve();

}

if (activeEditor.document.lineCount <= 1) {

return Promise.resolve();

}

// Hack, if the document doesn't contain an empty line at the end, then add it

// Else the library strips off the last line

const lastLine = activeEditor.document.lineAt(activeEditor.document.lineCount - 1);

let emptyLineAdded = Promise.resolve(true);

if (lastLine.text.trim().length > 0) {

// tslint:disable-next-line:no-any

emptyLineAdded = new Promise<any>((resolve, reject) => {

activeEditor.edit(builder => {

builder.insert(lastLine.range.end, os.EOL);

}).then(resolve, reject);

});

}

return emptyLineAdded.then(() => {

const processService = serviceContainer.get<IProcessService>(IProcessService);

const pythonExecutionFactory = serviceContainer.get<IPythonExecutionFactory>(IPythonExecutionFactory);

return new sortProvider.PythonImportSortProvider(pythonExecutionFactory, processService).sortImports(rootDir, activeEditor.document);

}).then(changes => {

if (!changes || changes!.length === 0) {

return;

}

return new Promise((resolve, reject) => activeEditor.edit(builder => changes.forEach(change => builder.replace(change.range, change.newText))).then(resolve, reject));

}).catch(error => {

const message = typeof error === 'string' ? error : (error.message ? error.message : error);

outChannel.appendLine(error);

outChannel.show();

vscode.window.showErrorMessage(message);

});

});

context.subscriptions.push(disposable);

}