"use client";

import React, { useState } from "react";
import { useAuth } from "@/hooks/useAuth";
import { useSearchParams } from "next/navigation";
import Link from "next/link";
import { isValidZAPhone } from "@/lib/phone";

export function RegisterForm() {
    const { register } = useAuth();
    const searchParams = useSearchParams();
    const raw = searchParams.get("redirect") || "";
    const redirectTo = raw.startsWith("/") && !raw.startsWith("//") ? raw : "/dashboard";
    const loginHref = redirectTo !== "/dashboard" ? `/login?redirect=${encodeURIComponent(redirectTo)}` : "/login";
    const [name, setName] = useState("");
    const [email, setEmail] = useState("");
    const [password, setPassword] = useState("");
    const [phoneNumber, setPhoneNumber] = useState("");
    const [notificationPreference, setNotificationPreference] = useState<"email" | "whatsapp" | "both">("email");
    const [accepted, setAccepted] = useState(false);
    const [loading, setLoading] = useState(false);
    const [error, setError] = useState<string | null>(null);

    const hasValidPhone = isValidZAPhone(phoneNumber);

    const getErrorMessage = (err: any) => {
        if (!err) return "Login failed";

        // If it's already a normal Error
        if (err.message && typeof err.message === "string") {
            // Handle case where message is accidentally JSON string
            try {
                const parsed = JSON.parse(err.message);
                return parsed.message || err.message;
            } catch {
                return err.message;
            }
        }

        // If API response object was thrown directly
        if (err.message) return err.message;

        return "Registration failed. Please try again.";
    };

    const onSubmit = async (e: React.FormEvent) => {
        e.preventDefault();
        if (!accepted) {
            setError("Please accept the Terms of Use and Privacy Policy before continuing.");
            return;
        }

        setError(null);
        setLoading(true);

        try {
            await register({
                name,
                email,
                password,
                phoneNumber: phoneNumber || undefined,
                notificationPreference: hasValidPhone ? notificationPreference : "email",
            });
            window.location.href = redirectTo;
        } catch (err: any) {
            setError(getErrorMessage(err) || "Registration failed. Please try again.");
        } finally {
            setLoading(false);
        }
    };

    return (
        <form onSubmit={onSubmit} className="space-y-4 max-w-sm w-full">
            <div>
                <label className="block text-sm font-medium mb-1">Full Name</label>
                <input
                    value={name}
                    onChange={(e) => setName(e.target.value)}
                    className="w-full border rounded px-3 py-2"
                    required
                />
            </div>

            <div>
                <label className="block text-sm font-medium mb-1">Email</label>
                <input
                    type="email"
                    value={email}
                    onChange={(e) => setEmail(e.target.value)}
                    className="w-full border rounded px-3 py-2"
                    required
                />
            </div>

            <div>
                <label className="block text-sm font-medium mb-1">Password</label>
                <input
                    type="password"
                    value={password}
                    onChange={(e) => setPassword(e.target.value)}
                    className="w-full border rounded px-3 py-2"
                    required
                />
            </div>

            <div>
                <label className="block text-sm font-medium mb-1">Phone Number (optional)</label>
                <input
                    value={phoneNumber}
                    onChange={(e) => setPhoneNumber(e.target.value)}
                    placeholder="e.g. 082 123 4567"
                    className="w-full border rounded px-3 py-2"
                />
            </div>

            {hasValidPhone && (
                <div>
                    <label className="block text-sm font-medium mb-1">Notification Preference</label>
                    <select
                        value={notificationPreference}
                        onChange={(e) => setNotificationPreference(e.target.value as "email" | "whatsapp" | "both")}
                        className="w-full border rounded px-3 py-2"
                    >
                        <option value="email">Email only</option>
                        <option value="whatsapp">WhatsApp only</option>
                        <option value="both">Email &amp; WhatsApp</option>
                    </select>
                </div>
            )}

            <div className="flex items-start gap-2">
                <input
                    id="terms"
                    type="checkbox"
                    checked={accepted}
                    onChange={(e) => setAccepted(e.target.checked)}
                    className="mt-1 h-4 w-4 border-gray-300 rounded accent-brand-600"
                    required
                />
                <label htmlFor="terms" className="text-sm text-gray-700 leading-snug">
                    I confirm that I’ve read and agree to the{" "}
                    <Link
                        href="/legal/terms"
                        target="_blank"
                        className="text-brand-600 hover:underline"
                    >
                        Terms of Use
                    </Link>{" "}
                    and{" "}
                    <Link
                        href="/legal/privacy"
                        target="_blank"
                        className="text-brand-600 hover:underline"
                    >
                        Privacy Policy
                    </Link>.
                </label>
            </div>

            <div className="mt-1">
                <a
                    href={loginHref}
                    className="text-xs text-brand-600 hover:underline"
                >
                    Already have an account? Sign in here.
                </a>
            </div>

            {error && <p className="text-sm text-red-600">{error}</p>}

            <button
                type="submit"
                disabled={loading || !accepted}
                className={`w-full rounded py-2 text-white transition ${
                    accepted
                        ? "bg-brand-600 hover:bg-brand-700"
                        : "bg-gray-400 cursor-not-allowed"
                }`}
            >
                {loading ? "Creating account..." : "Create account"}
            </button>
        </form>
    );
}