"use client";
import { createContext, useContext, useEffect, useState } from "react";

export interface AlumnoUser {
  idAlumno: string;
  nombres: string;
  apPaterno: string;
  apMaterno?: string;
  email: string;
  /** De qué tabla viene: SAM (sige_sam_v3.alumnos) o EMPRESA (sige_sam_empresa.alumnos). */
  origen: string;
}

interface SessionCtx {
  user: AlumnoUser | null;
  loading: boolean;
  login: (idAlumno: string, password: string) => Promise<void>;
  logout: () => Promise<void>;
}

const Ctx = createContext<SessionCtx | null>(null);

export function SessionProvider({ children }: { children: React.ReactNode }) {
  const [user, setUser] = useState<AlumnoUser | null>(null);
  const [loading, setLoading] = useState(true);

  useEffect(() => {
    fetch("/api/auth/me")
      .then((r) => (r.ok ? r.json() : null))
      .then((d) => setUser(d?.user ?? null))
      .catch(() => setUser(null))
      .finally(() => setLoading(false));
  }, []);

  async function login(idAlumno: string, password: string) {
    const r = await fetch("/api/auth/login", {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({ idAlumno, password })
    });
    const d = await r.json().catch(() => null);
    if (!r.ok || !d?.success) throw new Error(d?.message || "Credenciales inválidas");
    setUser(d.user);
  }

  async function logout() {
    await fetch("/api/auth/logout", { method: "POST" });
    setUser(null);
  }

  return <Ctx.Provider value={{ user, loading, login, logout }}>{children}</Ctx.Provider>;
}

export function useSession() {
  const ctx = useContext(Ctx);
  if (!ctx) throw new Error("useSession fuera de SessionProvider");
  return ctx;
}