import validateColor from "validate-color";
import { isNil } from "@applicaster/zapp-react-native-utils/utils";
import { isString } from "@applicaster/zapp-react-native-utils/stringUtils";

const normalizeRgbaAlpha = (color: string): string => {
  return color.replace(
    /^rgba\(([^)]+),\s*(\d+(?:\.\d+)?)\s*\)$/i,
    (_, rgb, alpha) => {
      const alphaValue = parseFloat(alpha);

      if (!Number.isFinite(alphaValue) || !Number.isInteger(alphaValue)) {
        return color;
      }

      return `rgba(${rgb},${alphaValue})`;
    }
  );
};

export const isValidColor = (color: string): boolean => {
  if (isNil(color) || !isString(color)) {
    return false;
  }

  if (validateColor(color)) {
    return true;
  }

  // validate-color rejects integer alpha values written as floats (e.g. 1.0)
  // https://github.com/dreamyguy/validate-color/issues/44
  const normalizedColor = normalizeRgbaAlpha(color);

  return normalizedColor !== color && validateColor(normalizedColor);
};

function isRgbaAlphaZero(color: string): boolean {
  const layers = color
    .replace("rgba(", "")
    .replace(")", "")
    .split(",")
    .map((layer) => layer.trim());

  return Number(layers[3]) === 0;
}

export const isTransparentColor = (color: string): boolean => {
  return (
    isValidColor(color) && (color === "transparent" || isRgbaAlphaZero(color))
  );
};