/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */

/*
 * Taken from https://github.com/Sergiioo/tslint-defocus
 * Copyright (c) 2016 Sergio Annecchiarico
 * MIT - https://github.com/Sergiioo/tslint-defocus/blob/master/LICENSE
 */

import * as Lint from 'tslint';
import * as ts from 'typescript';

export class Rule extends Lint.Rules.AbstractRule {

  public static metadata: Lint.IRuleMetadata = {
    ruleName: 'defocus',
    description: "Bans the use of `fdescribe` and 'fit' Jasmine functions.",
    rationale: 'It is all too easy to mistakenly commit a focussed Jasmine test suite or spec.',
    options: null,
    optionsDescription: 'Not configurable.',
    type: 'functionality',
    typescriptOnly: false,
  };

  public apply(sourceFile: ts.SourceFile): Lint.RuleFailure[] {
    return this.applyWithFunction(sourceFile, walk);
  }
}

function walk(ctx: Lint.WalkContext<void>) {
  return ts.forEachChild(ctx.sourceFile, function cb(node: ts.Node): void {
    if (node.kind === ts.SyntaxKind.CallExpression) {
      const expression = (node as ts.CallExpression).expression;
      const functionName = expression.getText();
      bannedFunctions.forEach((banned) => {
        if (banned === functionName) {
          ctx.addFailureAtNode(expression, failureMessage(functionName));
        }
      });
    }

    return ts.forEachChild(node, cb);
  });
}

const bannedFunctions: ReadonlyArray<string> = ['fdescribe', 'fit'];

const failureMessage = (functionName: string) => {
  return `Calls to '${functionName}' are not allowed.`;
};