"use client";

import { Button, TextInput } from "@/components/atoms";
import Link from "next/link";
import { useState } from "react";

interface FormState {
  name: string;
  phone: string;
  password: string;
}

interface FormErrors {
  name?: string;
  phone?: string;
  password?: string;
}

const PHONE_RE = /^0\d{9}$/;

function validate(data: FormState): FormErrors {
  const errors: FormErrors = {};
  if (!data.name.trim()) errors.name = "Name is required";
  if (!data.phone.trim()) {
    errors.phone = "Phone number is required";
  } else if (!PHONE_RE.test(data.phone.trim())) {
    errors.phone = "Must be 10 digits starting with 0 (e.g. 0912345678)";
  }
  if (!data.password) {
    errors.password = "Password is required";
  } else if (data.password.length < 6) {
    errors.password = "Password must be at least 6 characters";
  }
  return errors;
}

export default function CreateStaffPage() {
  const [form, setForm] = useState<FormState>({ name: "", phone: "", password: "" });
  const [errors, setErrors] = useState<FormErrors>({});
  const [apiError, setApiError] = useState<string | null>(null);
  const [success, setSuccess] = useState(false);
  const [loading, setLoading] = useState(false);
  const [showPassword, setShowPassword] = useState(false);

  function handleChange(e: React.ChangeEvent<HTMLInputElement>) {
    const { name, value } = e.target;
    setForm((prev) => ({ ...prev, [name]: value }));
    setErrors((prev) => ({ ...prev, [name]: undefined }));
    setApiError(null);
    setSuccess(false);
  }

  async function handleSubmit(e: React.FormEvent) {
    e.preventDefault();

    const validation = validate(form);
    if (Object.keys(validation).length > 0) {
      setErrors(validation);
      return;
    }

    setLoading(true);
    setApiError(null);
    try {
      const res = await fetch("/api/Staff/signup", {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({
          name: form.name.trim(),
          phone: form.phone.trim(),
          password: form.password,
        }),
      });

      if (res.ok) {
        setSuccess(true);
        setForm({ name: "", phone: "", password: "" });
        setErrors({});
      } else {
        const text = await res.text();
        setApiError(text || "Failed to create account. Please try again.");
      }
    } catch {
      setApiError("Connection error. Please check your network and try again.");
    } finally {
      setLoading(false);
    }
  }

  return (
    <div className="flex min-h-screen items-start justify-center bg-(--color-background) px-4 py-10">
      <div className="w-full max-w-md">
        <div className="mb-6">
          <Link
            href="/manager"
            className="mb-4 inline-flex items-center gap-1.5 text-sm text-(--color-text-muted) no-underline transition hover:text-(--color-primary)"
          >
            <i className="fa-solid fa-arrow-left"></i>
            Back to Dashboard
          </Link>
          <h1 className="text-foreground text-2xl font-bold">Create Staff Account</h1>
          <p className="mt-1 text-sm text-(--color-text-muted)">
            Fill in the details below to register a new staff member.
          </p>
        </div>

        {success && (
          <div className="mb-4 flex items-center gap-2 rounded-xl bg-green-50 px-4 py-3 text-sm font-medium text-green-700">
            <i className="fa-solid fa-circle-check"></i>
            Staff account created successfully.
          </div>
        )}

        {apiError && (
          <div className="mb-4 flex items-center gap-2 rounded-xl bg-red-50 px-4 py-3 text-sm font-medium text-red-600">
            <i className="fa-solid fa-circle-exclamation"></i>
            {apiError}
          </div>
        )}

        <div className="rounded-2xl border border-(--color-border-light) bg-white p-8 shadow-sm">
          <form onSubmit={handleSubmit} className="space-y-5" noValidate>
            <TextInput
              label="Full Name"
              name="name"
              value={form.name}
              onChange={handleChange}
              placeholder="Enter staff's full name"
              error={errors.name}
              autoComplete="name"
            />
            <TextInput
              label="Phone Number"
              name="phone"
              value={form.phone}
              onChange={handleChange}
              placeholder="0xxxxxxxxx"
              error={errors.phone}
              inputMode="tel"
              autoComplete="tel"
            />
            <TextInput
              label="Password"
              name="password"
              type={showPassword ? "text" : "password"}
              value={form.password}
              onChange={handleChange}
              placeholder="At least 6 characters"
              error={errors.password}
              icon={showPassword ? "fa-eye-slash" : "fa-eye"}
              onIconClick={() => setShowPassword((v) => !v)}
              autoComplete="new-password"
            />

            <Button
              type="submit"
              variant="primary"
              size="lg"
              icon="fa-user-plus"
              disabled={loading}
              className="mt-2 w-full"
            >
              {loading ? "Creating..." : "Create Account"}
            </Button>
          </form>
        </div>
      </div>
    </div>
  );
}