import { rgb } from "@app/services/pdfiumDocBuilder";

type RgbTuple = [number, number, number];

const defaultLightPalette: Record<
  | "headerBackground"
  | "accent"
  | "textPrimary"
  | "textMuted"
  | "boxBackground"
  | "boxBorder"
  | "warning"
  | "danger"
  | "success"
  | "neutral",
  RgbTuple
> = {
  headerBackground: [239, 246, 255],
  accent: [59, 130, 246],
  textPrimary: [30, 41, 59],
  textMuted: [100, 116, 139],
  boxBackground: [248, 250, 252],
  boxBorder: [226, 232, 240],
  warning: [234, 179, 8],
  danger: [248, 113, 113],
  success: [34, 197, 94],
  neutral: [148, 163, 184],
};

const toRgb = ([r, g, b]: RgbTuple) => rgb(r / 255, g / 255, b / 255);

/**
 * Utility function to get CSS variable values and convert them to RGB format.
 * Falls back to sensible defaults when the CSS variable cannot be resolved.
 */
function getCssVariableAsRgb(variableName: string, fallback: RgbTuple) {
  if (typeof window === "undefined") {
    return toRgb(fallback);
  }

  const value = getComputedStyle(document.documentElement)
    .getPropertyValue(variableName)
    .trim();

  if (!value) {
    console.warn(`CSS variable ${variableName} not found, using fallback`);
    return toRgb(fallback);
  }

  const [r, g, b] = value.split(" ").map(Number);

  if ([r, g, b].some((component) => Number.isNaN(component))) {
    console.warn(`Invalid CSS variable format for ${variableName}: ${value}`);
    return toRgb(fallback);
  }

  return rgb(r / 255, g / 255, b / 255);
}

export const colorPalette = {
  headerBackground: getCssVariableAsRgb(
    "--pdf-light-header-bg",
    defaultLightPalette.headerBackground,
  ),
  accent: getCssVariableAsRgb("--pdf-light-accent", defaultLightPalette.accent),
  textPrimary: getCssVariableAsRgb(
    "--pdf-light-text-primary",
    defaultLightPalette.textPrimary,
  ),
  textMuted: getCssVariableAsRgb(
    "--pdf-light-text-muted",
    defaultLightPalette.textMuted,
  ),
  boxBackground: getCssVariableAsRgb(
    "--pdf-light-box-bg",
    defaultLightPalette.boxBackground,
  ),
  boxBorder: getCssVariableAsRgb(
    "--pdf-light-box-border",
    defaultLightPalette.boxBorder,
  ),
  warning: getCssVariableAsRgb(
    "--pdf-light-warning",
    defaultLightPalette.warning,
  ),
  danger: getCssVariableAsRgb("--pdf-light-danger", defaultLightPalette.danger),
  success: getCssVariableAsRgb(
    "--pdf-light-success",
    defaultLightPalette.success,
  ),
  neutral: getCssVariableAsRgb(
    "--pdf-light-neutral",
    defaultLightPalette.neutral,
  ),
};
