// ANSI Colors helper - provides nested [tag]…[/] parsing and code-block wrapping.

// ANSI color/style codes
const CODES = {
  // text colors
  gray: 30, red: 31, green: 32, yellow: 33,
  blue: 34, pink: 35, cyan: 36, white: 37,
  // background colors
  bgGray: 40, bgOrange: 41, bgBlue: 42,
  bgTurquoise: 43, bgFirefly: 44, bgIndigo: 45,
  bgLightGray: 46, bgWhite: 47,
  // styles
  bold: 1, underline: 4,
  // reset
  reset: 0
};

/**
 * Escape literal brackets so users can write \[ and \] without triggering tags.
 */
export function escapeBrackets(str) {
  return str
    .replace(/\\\[/g, '__ESC_LB__')
    .replace(/\\\]/g, '__ESC_RB__');
}

/** Restore any escaped brackets after formatting. */
export function restoreBrackets(str) {
  return str
    .replace(/__ESC_LB__/g, '[')
    .replace(/__ESC_RB__/g, ']');
}

/**
 * Parse nested [tag1,tag2]…[/] patterns into ANSI codes (stack-based).
 */
export function formatAnsi(input) {
  const stack = [];
  let output = '';
  const pattern = /\[\/\]|\[([^\]]+)\]/g;
  let lastIndex = 0;
  let match;

  while ((match = pattern.exec(input)) !== null) {
    output += input.slice(lastIndex, match.index);

    if (match[0] === '[/]') {
      if (stack.length) stack.pop();
      output += `\u001b[${CODES.reset}m`;
      for (const tag of stack) {
        const code = CODES[tag] ?? CODES.gray;
        output += `\u001b[${code}m`;
      }
    } else {
      const tags = match[1].split(/[,;\s]+/).filter(Boolean);
      for (const tag of tags) {
        stack.push(tag);
        const code = CODES[tag] ?? CODES.gray;
        output += `\u001b[${code}m`;
      }
    }

    lastIndex = pattern.lastIndex;
  }

  output += input.slice(lastIndex);
  if (stack.length) output += `\u001b[${CODES.reset}m`;
  return output;
}

/**
 * Template-tag: ansi`[red]…[/] text`
 * Escapes brackets, parses ANSI, and restores literals.
 */
export function ansi(strings, ...values) {
  let built = '';
  for (let i = 0; i < strings.length; i++) {
    built += strings[i];
    if (i < values.length) built += values[i];
  }
  return restoreBrackets(formatAnsi(escapeBrackets(built)));
}

/** Wrap text in a ```ansi code block for Discord. */
export function wrapAnsi(text) {
  return '```ansi\n' + text + '\n```';
}

// Export raw codes for advanced use (e.g., ansitheme module)
export { CODES };