'use strict';

/**

* Class to hold lines that have been fetched from the document after they have been preprocessed.

*/

export class LineCache {

public endsInOperatorCache: Map<number, boolean>;

public getLine: (line: number) => string;

public lineCache: Map<number, string>;

public lineCount: number;

public constructor(getLine: (line: number) => string, lineCount: number) {

this.getLine = getLine;

this.lineCount = lineCount;

this.lineCache = new Map<number, string>();

this.endsInOperatorCache = new Map<number, boolean>();

}

// Returns [Line, EndsInOperator]

public addLineToCache(line: number): [string, boolean] {

const cleaned = cleanLine(this.getLine(line));

const endsInOperator = doesLineEndInOperator(cleaned);

this.lineCache.set(line, cleaned);

this.endsInOperatorCache.set(line, endsInOperator);

return [cleaned, endsInOperator];

}

public getEndsInOperatorFromCache(line: number): boolean {

const lineInCache = this.endsInOperatorCache.get(line);

if (lineInCache === undefined) {

return this.addLineToCache(line)[1];

}

return lineInCache;

}

public getLineFromCache(line: number): string {

const lineInCache = this.lineCache.get(line);

if (lineInCache === undefined) {

return this.addLineToCache(line)[0];

}

return lineInCache;

}

}

function isQuote(c: string) {

return c === '"' || c === '\'' || c === '`';

}

function isComment(c: string) {

return c === '#';

}

export function cleanLine(text: string): string {

let cleaned = '';

let withinQuotes = null;

for (let i = 0; i < text.length; i++) {

const c = text[i];

if (isQuote(c)) {

if (withinQuotes === null) {

withinQuotes = c;

} else if (withinQuotes === c) {

withinQuotes = null;

}

}

if (isComment(c) && !withinQuotes) {

break;

}

cleaned += c;

}

return (cleaned.trimEnd());

}

function doesLineEndInOperator(text: string) {

const endingOperatorIndex = text.search(/(\(|,|\+|!|\$|\^|&|\*|-|=|:|~|\||\/|\?|<|>|%.*%)(\s*|\s*#.*)$/);

const spacesOnlyIndex = text.search(/^\s*$/);

return ((endingOperatorIndex >= 0) || (spacesOnlyIndex >= 0));

}