"use client";

import {
  createContext,
  useCallback,
  useContext,
  useEffect,
  useMemo,
  useState,
  type ReactNode,
} from "react";
import { MESHKEE_API_BASE } from "@/lib/meshkee";

export type AuthUser = {
  id?: string | number;
  firstName?: string;
  lastName?: string;
  name?: string;
  cellNumber?: string;
  email?: string;
  role?: string;
  roles?: string[];
  isAdmin?: boolean;
};

type AuthContextValue = {
  user: AuthUser | null;
  token: string | null;
  loading: boolean;
  isAdmin: boolean;
  logout: () => void;
};

const AuthContext = createContext<AuthContextValue>({
  user: null,
  token: null,
  loading: true,
  isAdmin: false,
  logout: () => undefined,
});

const tokenKeys = [
  "accessToken",
  "meshkeeAccessToken",
  "meshkee_access_token",
  "meshkee-token",
];

function readToken() {
  try {
    for (const key of tokenKeys) {
      const value = window.localStorage.getItem(key);
      if (value) return value;
    }

    const authValue = window.localStorage.getItem("meshkee-auth");
    if (authValue) {
      const auth = JSON.parse(authValue) as { accessToken?: string };
      if (auth.accessToken) return auth.accessToken;
    }

    const cookies = document.cookie.split(";").map((item) => item.trim());
    for (const key of tokenKeys) {
      const prefix = `${key}=`;
      const cookie = cookies.find((item) => item.startsWith(prefix));
      if (cookie) return decodeURIComponent(cookie.slice(prefix.length));
    }
  } catch {
    return null;
  }

  return null;
}

function clearTokens() {
  try {
    tokenKeys.forEach((key) => {
      window.localStorage.removeItem(key);
      document.cookie = `${key}=; Max-Age=0; path=/; domain=.glassmond.com`;
      document.cookie = `${key}=; Max-Age=0; path=/`;
    });
    window.localStorage.removeItem("meshkee-auth");
  } catch {
    // External customer portal remains the source of truth for authentication.
  }
}

export function AuthProvider({ children }: { children: ReactNode }) {
  const [user, setUser] = useState<AuthUser | null>(null);
  const [token, setToken] = useState<string | null>(null);
  const [loading, setLoading] = useState(true);

  useEffect(() => {
    const accessToken = readToken();
    if (!accessToken) {
      setLoading(false);
      return;
    }

    setToken(accessToken);
    fetch(`${MESHKEE_API_BASE}/auth/me`, {
      headers: { Authorization: `Bearer ${accessToken}` },
    })
      .then(async (response) => {
        if (!response.ok) throw new Error("Unauthorized");
        return response.json() as Promise<{ user: AuthUser }>;
      })
      .then((data) => setUser(data.user))
      .catch(() => {
        clearTokens();
        setToken(null);
      })
      .finally(() => setLoading(false));
  }, []);

  const logout = useCallback(() => {
    clearTokens();
    setUser(null);
    setToken(null);
  }, []);

  const isAdmin = useMemo(() => {
    const roles = [user?.role, ...(user?.roles ?? [])]
      .filter(Boolean)
      .map((role) => String(role).toLowerCase());
    return Boolean(
      user?.isAdmin ||
        roles.some((role) => ["admin", "owner", "superadmin", "business_admin"].includes(role)),
    );
  }, [user]);

  return (
    <AuthContext.Provider value={{ user, token, loading, isAdmin, logout }}>
      {children}
    </AuthContext.Provider>
  );
}

export function useAuth() {
  return useContext(AuthContext);
}