/**

* Processes a quoted string, handling escape sequences

*

* @param {string} str - The input string containing the quoted segment.

* @param {number} start - The starting index of the quoted segment within the input string.

* @param {string} quote - The quote character used to delimit the quoted segment (e.g., '"' or "'").

* @returns {[string, number]} A tuple where the first element is the accumulated string and the second element is the position after the closing quote.

*/

export function processQuotedString(str: string, start: number, quote: string): [string, number] {

let accum = '';

let escaped = false;

for (let i = start; i < str.length; i++) {

const c = str[i];

if (escaped) {

if (c === quote) {

accum += c;

} else {

accum += '\\' + c;

}

escaped = false;

continue;

}

if (c === '\\') {

escaped = true;

continue;

}

if (c === quote) {

return [ accum, i+1 ];

}

accum += c;

}

if (escaped)

console.warn(`trailing backslash in '${str.slice(start)}'`)

console.warn(`unterminated ${quote}-quoted string '${str.slice(start)}'`);

return [ accum, str.length ];

}

/**

* Splits a shell command string into an array of arguments, handling quoted strings and escaped characters.

*

* @param {string} str - The shell command string to split.

* @returns {string[]} An array of arguments parsed from the input string.

*/

export function splitShellString(str: string): string[] {

let accum = '';

const result = [];

let escaped = false;

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

const c = str[i];

if (escaped) {

accum += c;

escaped = false;

continue;

}

if (c === '\\') {

escaped = true;

continue;

}

if (c === '"') {

const [ value, next ] = processQuotedString(str, i + 1, '"');

accum += value;

i = next - 1;

continue;

}

if (c === "'") {

const [ value, next ] = processQuotedString(str, i + 1, "'");

accum += value;

i = next - 1;

continue;

}

if (c === ' ' || c === '\t') {

result.push(accum);

accum = '';

continue;

}

accum += c;

}

if (escaped)

console.warn(`trailing backslash in '${str}'`)

if (accum)

result.push(accum);

return result;

}