"use client";

import { useState } from "react";

import { CheckCircle } from "lucide-react";

import { Drawer } from "@/components/ui/Drawer";
import {
  useSubmitPilotRequest,
  type PilotRequestPayload,
} from "@/lib/api/landing";

// ── Types ──────────────────────────────────────────────────────────────────

interface Props {
  open: boolean;
  onClose: () => void;
}

interface FormState {
  name: string;
  phone: string;
  email: string;
  company: string;
  message: string;
}

// ── Helpers ────────────────────────────────────────────────────────────────

/** Derives a human-readable tracking ID from the UUID string returned by backend.
 * Example: "7f3a8c2e-..." → "GD-7F3A8C2E"
 */
function deriveTrackingId(id: string): string {
  return "GD-" + id.replace(/-/g, "").slice(0, 8).toUpperCase();
}

// ── Component ──────────────────────────────────────────────────────────────

export function PilotRequestModal({ open, onClose }: Props) {
  const [form, setForm] = useState<FormState>({
    name: "",
    phone: "",
    email: "",
    company: "",
    message: "",
  });
  const [emailError, setEmailError] = useState<string>("");
  const [trackingId, setTrackingId] = useState<string | null>(null);

  const mutation = useSubmitPilotRequest();

  const EMAIL_RE = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;

  function handleChange(
    e: React.ChangeEvent<HTMLInputElement | HTMLTextAreaElement>,
  ) {
    const { name, value } = e.target;
    setForm((prev) => ({ ...prev, [name]: value }));
    if (name === "email") {
      setEmailError(value && !EMAIL_RE.test(value) ? "Некорректный email" : "");
    }
  }

  function handleSubmit(e: React.FormEvent<HTMLFormElement>) {
    e.preventDefault();
    if (!form.name.trim()) return;
    if (form.email && !EMAIL_RE.test(form.email)) {
      setEmailError("Некорректный email");
      return;
    }

    const payload: PilotRequestPayload = {
      name: form.name.trim(),
      source: "landing",
      ...(form.phone.trim() ? { phone: form.phone.trim() } : {}),
      ...(form.email.trim() ? { email: form.email.trim() } : {}),
      ...(form.company.trim() ? { company: form.company.trim() } : {}),
      ...(form.message.trim()
        ? { message: form.message.trim().slice(0, 2000) }
        : {}),
    };

    mutation.mutate(payload, {
      onSuccess: (data) => {
        setTrackingId(deriveTrackingId(data.id));
      },
    });
  }

  function handleClose() {
    setForm({ name: "", phone: "", email: "", company: "", message: "" });
    setEmailError("");
    setTrackingId(null);
    mutation.reset();
    onClose();
  }

  return (
    <Drawer open={open} onClose={handleClose} side="bottom">
      {/* Header */}
      <div
        style={{
          display: "flex",
          alignItems: "center",
          justifyContent: "space-between",
          padding: "20px 24px 0",
          marginBottom: 20,
        }}
      >
        <h2
          style={{
            margin: 0,
            fontSize: 18,
            fontWeight: 600,
            color: "var(--fg-primary)",
          }}
        >
          Запросить пилотный доступ
        </h2>
      </div>

      <div style={{ padding: "0 24px 32px" }}>
        {/* Success state */}
        {trackingId !== null ? (
          <div
            style={{
              display: "flex",
              flexDirection: "column",
              alignItems: "flex-start",
              gap: 12,
              padding: "24px 0",
            }}
          >
            <CheckCircle size={40} color="var(--success)" strokeWidth={1.5} />
            <p
              style={{
                margin: 0,
                fontSize: 16,
                fontWeight: 600,
                color: "var(--fg-primary)",
              }}
            >
              Заявка принята
            </p>
            <p
              style={{
                margin: 0,
                fontSize: 14,
                color: "var(--fg-secondary)",
                lineHeight: 1.5,
              }}
            >
              Мы свяжемся с вами в течение 1–2 рабочих дней. Номер заявки:{" "}
              <span
                style={{
                  fontVariantNumeric: "tabular-nums",
                  color: "var(--fg-primary)",
                }}
              >
                {trackingId}
              </span>
            </p>
            <button
              onClick={handleClose}
              style={{
                marginTop: 8,
                padding: "8px 20px",
                background: "var(--accent)",
                color: "#fff",
                border: "none",
                borderRadius: 8,
                fontSize: 14,
                fontWeight: 500,
                cursor: "pointer",
              }}
            >
              Закрыть
            </button>
          </div>
        ) : (
          /* Form */
          <form onSubmit={handleSubmit} noValidate>
            <div style={{ display: "flex", flexDirection: "column", gap: 16 }}>
              {/* Name */}
              <div>
                <label htmlFor="pilot-name" style={labelStyle}>
                  Имя *
                </label>
                <input
                  id="pilot-name"
                  name="name"
                  value={form.name}
                  onChange={handleChange}
                  required
                  placeholder="Алексей Кириллов"
                  style={inputStyle}
                />
              </div>

              {/* Company */}
              <div>
                <label htmlFor="pilot-company" style={labelStyle}>
                  Компания
                </label>
                <input
                  id="pilot-company"
                  name="company"
                  value={form.company}
                  onChange={handleChange}
                  placeholder="PRINZIP"
                  style={inputStyle}
                />
              </div>

              {/* Phone */}
              <div>
                <label htmlFor="pilot-phone" style={labelStyle}>
                  Телефон
                </label>
                <input
                  id="pilot-phone"
                  name="phone"
                  type="tel"
                  value={form.phone}
                  onChange={handleChange}
                  placeholder="+7 900 000-00-00"
                  style={inputStyle}
                />
              </div>

              {/* Email */}
              <div>
                <label htmlFor="pilot-email" style={labelStyle}>
                  Email
                </label>
                <input
                  id="pilot-email"
                  name="email"
                  type="email"
                  value={form.email}
                  onChange={handleChange}
                  placeholder="alex@prinzip.ru"
                  style={{
                    ...inputStyle,
                    borderColor: emailError
                      ? "var(--danger)"
                      : "var(--border-strong)",
                  }}
                />
                {emailError ? (
                  <span
                    style={{
                      fontSize: 12,
                      color: "var(--danger)",
                      marginTop: 4,
                      display: "block",
                    }}
                  >
                    {emailError}
                  </span>
                ) : null}
              </div>

              {/* Message */}
              <div>
                <label htmlFor="pilot-message" style={labelStyle}>
                  Сообщение
                </label>
                <textarea
                  id="pilot-message"
                  name="message"
                  value={form.message}
                  onChange={handleChange}
                  placeholder="Расскажите о вашем проекте или вопросе..."
                  rows={4}
                  maxLength={2000}
                  style={{
                    ...inputStyle,
                    resize: "vertical",
                    minHeight: 96,
                    fontFamily: "inherit",
                  }}
                />
                <span
                  style={{
                    fontSize: 12,
                    color: "var(--fg-tertiary)",
                    marginTop: 2,
                    display: "block",
                  }}
                >
                  {form.message.length} / 2000
                </span>
              </div>

              {/* Error */}
              {mutation.isError ? (
                <div
                  style={{
                    padding: "10px 14px",
                    background: "var(--danger-soft)",
                    borderRadius: 8,
                    fontSize: 13,
                    color: "var(--danger)",
                  }}
                >
                  {mutation.error instanceof Error
                    ? mutation.error.message
                    : "Ошибка отправки. Попробуйте позже."}
                </div>
              ) : null}

              {/* Submit */}
              <button
                type="submit"
                disabled={mutation.isPending || !form.name.trim()}
                style={{
                  padding: "12px 24px",
                  background:
                    mutation.isPending || !form.name.trim()
                      ? "var(--accent-soft)"
                      : "var(--accent)",
                  color:
                    mutation.isPending || !form.name.trim()
                      ? "var(--accent)"
                      : "#fff",
                  border: "none",
                  borderRadius: 8,
                  fontSize: 15,
                  fontWeight: 600,
                  cursor:
                    mutation.isPending || !form.name.trim()
                      ? "not-allowed"
                      : "pointer",
                  opacity: mutation.isPending || !form.name.trim() ? 0.7 : 1,
                  transition: "opacity 0.15s",
                }}
              >
                {mutation.isPending ? "Отправка..." : "Отправить заявку"}
              </button>
            </div>
          </form>
        )}
      </div>
    </Drawer>
  );
}

// ── Shared styles ──────────────────────────────────────────────────────────

const labelStyle: React.CSSProperties = {
  display: "block",
  fontSize: 12,
  fontWeight: 500,
  textTransform: "uppercase" as const,
  letterSpacing: "0.04em",
  color: "var(--fg-secondary)",
  marginBottom: 6,
};

const inputStyle: React.CSSProperties = {
  width: "100%",
  padding: "9px 12px",
  border: "1px solid var(--border-strong)",
  borderRadius: 8,
  fontSize: 14,
  color: "var(--fg-primary)",
  background: "var(--bg-card)",
  outline: "none",
  boxSizing: "border-box" as const,
};