"use client";
import React, { useState, useEffect, useRef } from "react";
import { motion, AnimatePresence } from "motion/react";
import { X, ShieldCheck, Phone, Key, LogIn, ArrowRight, RefreshCw } from "lucide-react";
import { authService } from "../lib/services/authService";
import { useUserStore } from "../lib/store/userStore";
import { toast } from "sonner";
import { toPersian } from "../lib/utils";

interface LoginModalProps {
  isOpen: boolean;
  onClose: () => void;
  onLogin: () => void;
  petName?: string;
  isAdvisorContext?: boolean;
}

export default function LoginModal({ isOpen, onClose, onLogin, petName, isAdvisorContext }: LoginModalProps) {
  const [step, setStep] = useState<"phone" | "otp">("phone");
  const [phoneNumber, setPhoneNumber] = useState("");
  const [otpCode, setOtpCode] = useState("");
  const [isLoading, setIsLoading] = useState(false);
  const [countdown, setCountdown] = useState(0);
  const { fetchProfile } = useUserStore();
  const otpInputRef = useRef<HTMLInputElement>(null);

  useEffect(() => {
    if (step === "otp") {
      const timer = setTimeout(() => {
        otpInputRef.current?.focus();
      }, 100);
      return () => clearTimeout(timer);
    }
  }, [step]);

  const handleVerifyOtpWithCode = React.useCallback(async (code: string) => {
    const cleanCode = code.trim();
    if (cleanCode.length !== 5) {
      toast.error("کد تایید باید ۵ رقم باشد");
      return;
    }

    setIsLoading(true);
    try {
      const response = await authService.verifyOtp(phoneNumber.trim(), cleanCode);
      if (response.success) {
        await fetchProfile();
        toast.success("ورود با موفقیت انجام شد");
        onLogin();
        onClose();
      }
    } catch (err: unknown) {
      const errObj = err as { message?: string };
      toast.error(errObj.message || "کد تایید اشتباه است");
    } finally {
      setIsLoading(false);
    }
  }, [phoneNumber, fetchProfile, onLogin, onClose]);

  // WebOTP API & Auto-Submit
  useEffect(() => {
    if (step === "otp" && typeof window !== "undefined" && "OTPCredential" in window) {
      const ac = new AbortController();
      const creds = (navigator as unknown as { credentials?: { get?: (opt: unknown) => Promise<{ code?: string }> } }).credentials;
      if (creds && creds.get) {
        creds.get({
          otp: { transport: ["sms"] },
          signal: ac.signal,
        })
        .then((otp) => {
          if (otp && otp.code) {
            setOtpCode(otp.code);
            handleVerifyOtpWithCode(otp.code);
          }
        })
        .catch(() => {});
      }

      return () => ac.abort();
    }
  }, [step, handleVerifyOtpWithCode]);

  const handleOtpInputChange = (e: React.ChangeEvent<HTMLInputElement>) => {
    const val = e.target.value.replace(/[^0-9]/g, "").slice(0, 5);
    setOtpCode(val);
    if (val.length === 5) {
      handleVerifyOtpWithCode(val);
    }
  };

  const handleOtpPaste = (e: React.ClipboardEvent<HTMLInputElement>) => {
    const pasted = e.clipboardData.getData("text").replace(/[^0-9]/g, "").slice(0, 5);
    if (pasted.length === 5) {
      e.preventDefault();
      setOtpCode(pasted);
      handleVerifyOtpWithCode(pasted);
    }
  };

  // Reset modal state when closed or opened
  useEffect(() => {
    if (!isOpen) {
      Promise.resolve().then(() => {
        setStep("phone");
        setPhoneNumber("");
        setOtpCode("");
        setIsLoading(false);
        setCountdown(0);
      });
    }
  }, [isOpen]);

  // Countdown timer for OTP resend
  useEffect(() => {
    if (countdown > 0) {
      const timer = setTimeout(() => setCountdown(countdown - 1), 1000);
      return () => clearTimeout(timer);
    }
  }, [countdown]);

  const handleSendOtp = async (e: React.FormEvent) => {
    e.preventDefault();
    const cleanPhone = phoneNumber.trim();
    if (!/^09\d{9}$/.test(cleanPhone)) {
      toast.error("شماره موبایل باید با ۰۹ شروع شده و ۱۱ رقم باشد");
      return;
    }

    setIsLoading(true);
    try {
      const res = await authService.sendOtp(cleanPhone);
      const resObj = res as unknown as { code?: string };
      if (resObj.code) {
        toast.info(`کد تایید (تست): ${resObj.code}`, { duration: 10000 });
      } else {
        toast.success("کد تایید پیامک شد");
      }
      setStep("otp");
      setCountdown(120); // 2 minutes cooldown
    } catch (err: unknown) {
      const errObj = err as { message?: string };
      toast.error(errObj.message || "خطا در ارسال کد تایید");
    } finally {
      setIsLoading(false);
    }
  };

  const handleVerifyOtp = async (e: React.FormEvent) => {
    e.preventDefault();
    handleVerifyOtpWithCode(otpCode);
  };

  const handleResendOtp = async () => {
    if (countdown > 0) return;
    setIsLoading(true);
    try {
      await authService.sendOtp(phoneNumber.trim());
      toast.success("کد تایید جدید ارسال شد");
      setCountdown(120);
    } catch (err: unknown) {
      const errObj = err as { message?: string };
      toast.error(errObj.message || "خطا در ارسال مجدد کد تایید");
    } finally {
      setIsLoading(false);
    }
  };

  return (
    <AnimatePresence>
      {isOpen && (
        <div className="fixed inset-0 z-[200] flex items-center justify-center p-4">
          {/* Backdrop */}
          <motion.div
            initial={{ opacity: 0 }}
            animate={{ opacity: 1 }}
            exit={{ opacity: 0 }}
            onClick={onClose}
            className="absolute inset-0 bg-medical-gray-900/60 backdrop-blur-md"
          />

          {/* Modal Container */}
          <motion.div
            initial={{ opacity: 0, scale: 0.9, y: 20 }}
            animate={{ opacity: 1, scale: 1, y: 0 }}
            exit={{ opacity: 0, scale: 0.9, y: 20 }}
            className="bg-white w-full max-w-md rounded-[3.5rem] p-10 relative z-10 shadow-2xl overflow-hidden font-vazir border border-medical-gray-100"
            dir="rtl"
          >
            {/* Top color indicator */}
            <div className="absolute top-0 left-0 w-full h-2 bg-gradient-to-r from-canina-blue to-indigo-500" />

            {/* Close Button */}
            <button
              onClick={onClose}
              className="absolute top-8 left-8 p-2 rounded-full hover:bg-medical-gray-50 text-medical-gray-400 hover:text-medical-gray-600 transition-colors"
            >
              <X className="w-6 h-6" />
            </button>

            {/* Header info */}
            <div className="text-center mb-8">
              <div className="w-20 h-20 bg-canina-blue/10 rounded-[2.5rem] flex items-center justify-center mx-auto mb-6 shadow-inner">
                <ShieldCheck className="w-10 h-10 text-canina-blue" />
              </div>
              <h3 className="text-3xl font-black text-medical-gray-900 mb-2 italic">
                ورود به کنینا
              </h3>
              {isAdvisorContext ? (
                <p className="text-medical-gray-500 font-bold leading-relaxed px-2 text-sm">
                  تحلیل سلامت <span className="text-canina-blue">{petName || "همدم شما"}</span> آماده است! برای مشاهده رژیم مکمل پیشنهادی و ذخیره شناسنامه، وارد شوید.
                </p>
              ) : (
                <p className="text-medical-gray-500 font-bold text-sm">برای دسترسی به پنل مدیریت سلامت، وارد شوید</p>
              )}
            </div>

            {/* Step-based Forms */}
            <AnimatePresence mode="wait">
              {step === "phone" ? (
                <motion.form
                  key="phone-form"
                  initial={{ opacity: 0, x: 20 }}
                  animate={{ opacity: 1, x: 0 }}
                  exit={{ opacity: 0, x: -20 }}
                  onSubmit={handleSendOtp}
                  className="space-y-6"
                >
                  <div className="space-y-2">
                    <label className="text-[10px] font-black text-medical-gray-400 uppercase tracking-widest block">شماره موبایل</label>
                    <div className="relative">
                      <Phone className="absolute right-4 top-1/2 -translate-y-1/2 w-5 h-5 text-medical-gray-400" />
                      <input
                        autoFocus
                        type="tel"
                        maxLength={11}
                        placeholder="مثال: ۰۹۱۲۳۴۵۶۷۸۹"
                        value={phoneNumber}
                        onChange={(e) => setPhoneNumber(e.target.value.replace(/[^0-9]/g, ''))}
                        disabled={isLoading}
                        className="w-full bg-medical-gray-50 border border-medical-gray-200 rounded-2xl py-4 pr-12 pl-4 focus:ring-2 focus:ring-canina-blue/20 focus:border-canina-blue outline-none font-bold text-lg text-left tracking-widest"
                      />
                    </div>
                  </div>

                  <button
                    type="submit"
                    disabled={isLoading || phoneNumber.length < 11}
                    className="w-full py-5 bg-canina-blue text-white rounded-2xl font-black text-xl hover:bg-indigo-700 disabled:opacity-50 disabled:cursor-not-allowed transition-all shadow-xl shadow-canina-blue/20 flex items-center justify-center gap-3 cursor-pointer"
                  >
                    {isLoading ? (
                      <RefreshCw className="w-6 h-6 animate-spin" />
                    ) : (
                      <>
                        <LogIn className="w-6 h-6" />
                        ارسال کد تایید
                      </>
                    )}
                  </button>
                </motion.form>
              ) : (
                <motion.form
                  key="otp-form"
                  initial={{ opacity: 0, x: 20 }}
                  animate={{ opacity: 1, x: 0 }}
                  exit={{ opacity: 0, x: -20 }}
                  onSubmit={handleVerifyOtp}
                  className="space-y-6"
                >
                  <div className="space-y-2">
                    <div className="flex justify-between items-center">
                      <label className="text-[10px] font-black text-medical-gray-400 uppercase tracking-widest">کد تایید پیامکی</label>
                      <button
                        type="button"
                        onClick={() => setStep("phone")}
                        className="text-[10px] font-black text-canina-blue flex items-center gap-1 hover:underline"
                      >
                        <ArrowRight className="w-3 h-3" />
                        ویرایش شماره
                      </button>
                    </div>
                    <div className="relative">
                      <Key className="absolute right-4 top-1/2 -translate-y-1/2 w-5 h-5 text-medical-gray-400" />
                      <input
                        ref={otpInputRef}
                        type="text"
                        maxLength={5}
                        autoComplete="one-time-code"
                        placeholder="کد ۵ رقمی"
                        value={otpCode}
                        onChange={handleOtpInputChange}
                        onPaste={handleOtpPaste}
                        disabled={isLoading}
                        className="w-full bg-medical-gray-50 border border-medical-gray-200 rounded-2xl py-4 pr-12 pl-4 focus:ring-2 focus:ring-canina-blue/20 focus:border-canina-blue outline-none font-black text-2xl text-center tracking-[0.5em]"
                      />
                    </div>
                    <p className="text-[10px] text-medical-gray-400 font-bold text-center mt-2">
                      کد تایید به شماره {toPersian(phoneNumber)} ارسال گردید.
                    </p>
                  </div>

                  <div className="flex justify-center">
                    {countdown > 0 ? (
                      <span className="text-xs font-bold text-medical-gray-400 font-vazir">
                        ارسال مجدد کد پس از {toPersian(countdown)} ثانیه
                      </span>
                    ) : (
                      <button
                        type="button"
                        onClick={handleResendOtp}
                        disabled={isLoading}
                        className="text-xs font-black text-canina-blue hover:underline flex items-center gap-1.5"
                      >
                        <RefreshCw className="w-3.5 h-3.5" />
                        ارسال مجدد کد تایید
                      </button>
                    )}
                  </div>

                  <button
                    type="submit"
                    disabled={isLoading || otpCode.length < 5}
                    className="w-full py-5 bg-canina-blue text-white rounded-2xl font-black text-xl hover:bg-indigo-700 disabled:opacity-50 disabled:cursor-not-allowed transition-all shadow-xl shadow-canina-blue/20 flex items-center justify-center gap-3 cursor-pointer"
                  >
                    {isLoading ? (
                      <RefreshCw className="w-6 h-6 animate-spin" />
                    ) : (
                      <>
                        <LogIn className="w-6 h-6" />
                        ورود و تایید حساب
                      </>
                    )}
                  </button>
                </motion.form>
              )}
            </AnimatePresence>
          </motion.div>
        </div>
      )}
    </AnimatePresence>
  );
}