export const DEFAULT_PINK_RGB = '202, 8, 234';
export const DEFAULT_BLUE_RGB = '4, 148, 247';

/**
 * Convert a 6-digit hex color to an "r, g, b" string.
 * Returns null for invalid input.
 */
export const hexToRgb = (hex: string): string | null => {
  if (!hex) return null;

  const cleanHex = hex.replace(/^#/, '');

  if (!/^[0-9A-Fa-f]{6}$/.test(cleanHex)) return null;

  const r = parseInt(cleanHex.substring(0, 2), 16);
  const g = parseInt(cleanHex.substring(2, 4), 16);
  const b = parseInt(cleanHex.substring(4, 6), 16);

  return `${r}, ${g}, ${b}`;
};

/**
 * Convert hex (3 or 6 digit) to "r,g,b" string (no spaces).
 * Used for inline rgba() CSS values.
 */
export const hexToRGB = (h: string): string => {
  let r: number | string = 0;
  let g: number | string = 0;
  let b: number | string = 0;

  if (h.length === 4) {
    r = `0x${h[1]}${h[1]}`;
    g = `0x${h[2]}${h[2]}`;
    b = `0x${h[3]}${h[3]}`;
  } else if (h.length === 7) {
    r = `0x${h[1]}${h[2]}`;
    g = `0x${h[3]}${h[4]}`;
    b = `0x${h[5]}${h[6]}`;
  }

  return `${+r},${+g},${+b}`;
};

/**
 * Convert hex to rgba() CSS string.
 * Supports shorthand (#03F) and full (#0033FF) hex values.
 */
export const hexToRgba = (hex: string, alpha = 1): string => {
  const expandedHex =
    hex.length === 4
      ? '#' + hex[1] + hex[1] + hex[2] + hex[2] + hex[3] + hex[3]
      : hex;

  const r = parseInt(expandedHex.substring(1, 3), 16);
  const g = parseInt(expandedHex.substring(3, 5), 16);
  const b = parseInt(expandedHex.substring(5, 7), 16);

  return `rgb(${r} ${g} ${b} / ${alpha})`;
};

/**
 * Convert comma-separated RGB string to hex (e.g. "255,0,128" -> "#ff0080").
 */
export const RGBToHex = (rgbColor: string): string => {
  const [r, g, b] = rgbColor.split(',').map(c => parseInt(c, 10));

  return '#' + ((1 << 24) + (r << 16) + (g << 8) + b).toString(16).slice(1);
};

/**
 * Convert CSS rgb/rgba string to hex (e.g. "rgb(255 0 128 / 1)" -> "#ff0080").
 */
export const rgbaToHex = (rgba: string): string => {
  const parts: RegExpMatchArray | null = rgba.match(/(\d+) \s*(\d+) \s*(\d+)/);

  if (!parts) {
    return '#FFFFFF';
  }

  const r = parseInt(parts[1]).toString(16).padStart(2, '0');
  const g = parseInt(parts[2]).toString(16).padStart(2, '0');
  const b = parseInt(parts[3]).toString(16).padStart(2, '0');

  return `#${r}${g}${b}`;
};