tweakcn/components/theme-provider.tsx

"use client";

import { createContext, useContext, useEffect } from "react";
import { useEditorStore } from "../store/editor-store";
import { colorFormatter } from "../utils/color-converter";
import { setShadowVariables } from "@/utils/shadows";
import { applyStyleToElement } from "@/utils/apply-style-to-element";
import { ThemeStyleProps, ThemeStyles } from "@/types/theme";
import { useThemePresetFromUrl } from "@/hooks/use-theme-preset-from-url";
import { COMMON_STYLES } from "@/config/theme";

type Theme = "dark" | "light";

type ThemeProviderProps = {
  children: React.ReactNode;
  defaultTheme?: Theme;
};

type Coords = { x: number; y: number };

type ThemeProviderState = {
  theme: Theme;
  setTheme: (theme: Theme) => void;
  toggleTheme: (coords?: Coords) => void;
};

const COMMON_NON_COLOR_KEYS = COMMON_STYLES;

const initialState: ThemeProviderState = {
  theme: "light",
  setTheme: () => null,
  toggleTheme: () => null,
};

const ThemeProviderContext = createContext<ThemeProviderState>(initialState);

// Helper functions
const applyCommonStyles = (root: HTMLElement, themeStyles: ThemeStyleProps) => {
  Object.entries(themeStyles)
    .filter(([key]) =>
      COMMON_NON_COLOR_KEYS.includes(key as (typeof COMMON_NON_COLOR_KEYS)[number])
    )
    .forEach(([key, value]) => {
      if (typeof value === "string") {
        applyStyleToElement(root, key, value);
      }
    });
};

const applyThemeColors = (
  root: HTMLElement,
  themeStyles: ThemeStyles,
  mode: Theme
) => {
  Object.entries(themeStyles[mode]).forEach(([key, value]) => {
    if (
      typeof value === "string" &&
      !COMMON_NON_COLOR_KEYS.includes(key as (typeof COMMON_NON_COLOR_KEYS)[number])
    ) {
      const hslValue = colorFormatter(value, "hsl", "4");
      applyStyleToElement(root, key, hslValue);
    }
  });
};

const updateThemeClass = (root: HTMLElement, mode: Theme) => {
  if (mode === "light") {
    root.classList.remove("dark");
  } else {
    root.classList.add("dark");
  }
};

export function ThemeProvider({ children, ...props }: ThemeProviderProps) {
  const { themeState, setThemeState } = useEditorStore();

  // Handle theme preset from URL
  useThemePresetFromUrl();

  useEffect(() => {
    const root = window.document.documentElement;
    const { currentMode: mode, styles: themeStyles } = themeState;

    updateThemeClass(root, mode);
    applyCommonStyles(root, themeStyles.light);
    applyThemeColors(root, themeStyles, mode);
    setShadowVariables(themeState);
  }, [themeState]);

  const handleThemeChange = (newMode: Theme) => {
    setThemeState({ ...themeState, currentMode: newMode });
  };

  const handleThemeToggle = (coords?: Coords) => {
    const root = document.documentElement;
    const newMode = themeState.currentMode === "light" ? "dark" : "light";

    const prefersReducedMotion = window.matchMedia(
      "(prefers-reduced-motion: reduce)"
    ).matches;

    if (!document.startViewTransition || prefersReducedMotion) {
      handleThemeChange(newMode);
      return;
    }

    if (coords) {
      root.style.setProperty("--x", `${coords.x}px`);
      root.style.setProperty("--y", `${coords.y}px`);
    }

    document.startViewTransition(() => {
      handleThemeChange(newMode);
    });
  };

  const value: ThemeProviderState = {
    theme: themeState.currentMode,
    setTheme: handleThemeChange,
    toggleTheme: handleThemeToggle,
  };

  return (
    <ThemeProviderContext.Provider {...props} value={value}>
      {children}
    </ThemeProviderContext.Provider>
  );
}

export const useTheme = () => {
  const context = useContext(ThemeProviderContext);

  if (context === undefined) {
    throw new Error("useTheme must be used within a ThemeProvider");
  }

  return context;
};