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

// Licensed under the MIT License.

'use strict';

import { Position, Range, TextDocument } from 'vscode';

import { ITextIterator } from './types';

export class TextIterator implements ITextIterator {

private text: string;

constructor(text: string) {

this.text = text;

}

public charCodeAt(index: number): number {

if (index >= 0 && index < this.text.length) {

return this.text.charCodeAt(index);

}

return 0;

}

public get length(): number {

return this.text.length;

}

public getText(): string {

return this.text;

}

}

export class DocumentTextIterator implements ITextIterator {

public readonly length: number;

private document: TextDocument;

constructor(document: TextDocument) {

this.document = document;

const lastIndex = this.document.lineCount - 1;

const lastLine = this.document.lineAt(lastIndex);

const end = new Position(lastIndex, lastLine.range.end.character);

this.length = this.document.offsetAt(end);

}

public charCodeAt(index: number): number {

const position = this.document.positionAt(index);

return this.document.getText(new Range(position, position.translate(0, 1))).charCodeAt(position.character);

}

public getText(): string {

return this.document.getText();

}

}