"use client";

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

type ToastKind = "success" | "error" | "info";
type Toast = { id: number; kind: ToastKind; message: string };

type ToastContextValue = {
  toast: (message: string, kind?: ToastKind) => void;
  success: (message: string) => void;
  error: (message: string) => void;
};

const ToastContext = createContext<ToastContextValue | null>(null);

let _id = 0;

export function ToastProvider({ children }: { children: React.ReactNode }) {
  const [toasts, setToasts] = useState<Toast[]>([]);

  const remove = useCallback((id: number) => {
    setToasts((prev) => prev.filter((t) => t.id !== id));
  }, []);

  const toast = useCallback(
    (message: string, kind: ToastKind = "info") => {
      const id = ++_id;
      setToasts((prev) => [...prev, { id, kind, message }]);
      setTimeout(() => remove(id), 4500);
    },
    [remove]
  );

  const value: ToastContextValue = {
    toast,
    success: (m) => toast(m, "success"),
    error: (m) => toast(m, "error"),
  };

  return (
    <ToastContext.Provider value={value}>
      {children}
      <div
        className="pointer-events-none fixed inset-x-0 bottom-4 z-[100] flex flex-col items-center gap-2 px-4"
        aria-live="polite"
        role="status"
      >
        {toasts.map((t) => (
          <button
            key={t.id}
            onClick={() => remove(t.id)}
            className={`pointer-events-auto w-full max-w-md rounded-xl border px-4 py-3 text-left text-sm shadow-lg backdrop-blur transition ${
              t.kind === "success"
                ? "border-good/40 bg-good/15 text-good"
                : t.kind === "error"
                  ? "border-bad/40 bg-bad/15 text-bad"
                  : "border-edge bg-panel/90 text-slate-200"
            }`}
          >
            {t.message}
          </button>
        ))}
      </div>
    </ToastContext.Provider>
  );
}

export function useToast(): ToastContextValue {
  const ctx = useContext(ToastContext);
  if (!ctx) {
    // No-op fallback so components don't crash outside the provider.
    return { toast: () => {}, success: () => {}, error: () => {} };
  }
  return ctx;
}