"use client"

import type React from "react"

import { Button } from "@/components/ui/button"
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "@/components/ui/card"
import { Input } from "@/components/ui/input"
import { Label } from "@/components/ui/label"
import { Textarea } from "@/components/ui/textarea"
import { Checkbox } from "@/components/ui/checkbox"
import { RadioGroup, RadioGroupItem } from "@/components/ui/radio-group"
import Link from "next/link"
import { useState } from "react"
import {
  EVENT_SHORT,
  EVENT_FULL_NAME,
  EVENT_DATES,
  EVENT_LOCATION,
  PRICING_TIERS,
  PROCESSING_FEE_PERCENT,
  ACCOMMODATION_VENUES,
  ACCOMMODATION_MAP,
  ACCOMMODATION_NIGHTS,
  LINKS,
} from "@/lib/event.config"

// Determine current tier client-side
function getClientTier() {
  const now = new Date().toISOString().slice(0, 10)
  return PRICING_TIERS.find((t) => now < t.cutoff) ?? PRICING_TIERS[PRICING_TIERS.length - 1]
}

export default function RegisterPage() {
  const [step, setStep] = useState<"form" | "payment">("form")
  const [isSubmitting, setIsSubmitting] = useState(false)
  const [includeAccommodation, setIncludeAccommodation] = useState(true)
  const [wantFood, setWantFood] = useState(false)
  const [selectedVenueKey, setSelectedVenueKey] = useState(ACCOMMODATION_VENUES[0]?.key || "")
  const [accommodationType, setAccommodationType] = useState(
    ACCOMMODATION_VENUES[0]?.options[0]?.id || ""
  )
  const [formData, setFormData] = useState({
    name: "",
    email: "",
    contact: "",
    contributions: "",
    expectations: "",
    howHeard: "",
    dietary: [] as string[],
    dietaryOther: "",
    crewConsent: "",
  })

  const tier = getClientTier()
  const baseTicketPrice = tier.price

  const accommodationPrice = ACCOMMODATION_MAP[accommodationType]?.price ?? 0
  const subtotalPrice =
    baseTicketPrice +
    (includeAccommodation ? accommodationPrice : 0)
  const processingFee = Math.round(subtotalPrice * PROCESSING_FEE_PERCENT * 100) / 100
  const totalPrice = subtotalPrice + processingFee

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault()
    // Validate required fields
    if (
      !formData.name ||
      !formData.email ||
      !formData.contact ||
      !formData.contributions ||
      !formData.expectations ||
      !formData.crewConsent
    ) {
      alert("Please fill in all required fields")
      return
    }

    setIsSubmitting(true)

    try {
      // Submit registration to Google Sheet first
      const dietaryString =
        formData.dietary.join(", ") +
        (formData.dietaryOther ? `, ${formData.dietaryOther}` : "")

      const response = await fetch("/api/register", {
        method: "POST",
        headers: {
          "Content-Type": "application/json",
        },
        body: JSON.stringify({
          name: formData.name,
          email: formData.email,
          contact: formData.contact,
          contributions: formData.contributions,
          expectations: formData.expectations,
          howHeard: formData.howHeard,
          dietary: dietaryString,
          crewConsent: formData.crewConsent,
          wantFood,
        }),
      })

      if (!response.ok) {
        throw new Error("Failed to record registration")
      }

      // Proceed to payment step
      setStep("payment")
    } catch (error) {
      console.error("Registration error:", error)
      alert("There was an error recording your registration. Please try again.")
    } finally {
      setIsSubmitting(false)
    }
  }

  const handleDietaryChange = (value: string, checked: boolean) => {
    setFormData((prev) => ({
      ...prev,
      dietary: checked ? [...prev.dietary, value] : prev.dietary.filter((item) => item !== value),
    }))
  }

  // Pricing summary line
  const pricingSummary = PRICING_TIERS.map(
    (t) => `€${t.price} ${t.label}${t === tier ? " (current)" : ""}`
  ).join(" · ")

  if (step === "payment") {
    return (
      <div className="min-h-screen bg-background">
        {/* Header */}
        <header className="border-b">
          <div className="container mx-auto px-4 py-4">
            <Link href={LINKS.website} className="text-2xl font-bold text-primary">
              {EVENT_SHORT}
            </Link>
          </div>
        </header>

        <main className="container mx-auto px-4 py-12 max-w-5xl">
          <div className="text-center mb-12">
            <h1 className="text-4xl md:text-5xl font-bold mb-4">Complete Your Registration</h1>
            <p className="text-xl text-muted-foreground">Choose your payment method</p>
          </div>

          <Card className="mb-8 border-primary/40">
            <CardHeader>
              <CardTitle>Event Registration</CardTitle>
              <CardDescription>
                {pricingSummary}
              </CardDescription>
            </CardHeader>
            <CardContent>
              <div className="space-y-4">
                {/* Ticket */}
                <div className="flex items-start justify-between py-4 border-b border-border">
                  <div>
                    <div className="font-medium">{EVENT_SHORT} Ticket</div>
                    <div className="text-sm text-muted-foreground">
                      {pricingSummary}
                    </div>
                  </div>
                  <span className="text-lg font-semibold whitespace-nowrap ml-4">€{baseTicketPrice.toFixed(2)}</span>
                </div>

                {/* Accommodation */}
                <div className="py-4 border-b border-border">
                  <div className="flex items-start gap-3">
                    <Checkbox
                      id="include-accommodation"
                      checked={includeAccommodation}
                      onCheckedChange={(checked) => setIncludeAccommodation(checked as boolean)}
                      className="mt-1"
                    />
                    <div className="flex-1">
                      <div className="flex justify-between items-start">
                        <Label htmlFor="include-accommodation" className="font-medium cursor-pointer">
                          Accommodation ({ACCOMMODATION_NIGHTS} nights)
                        </Label>
                        {includeAccommodation && (
                          <span className="text-lg font-semibold whitespace-nowrap ml-4">€{accommodationPrice.toFixed(2)}</span>
                        )}
                      </div>
                      {includeAccommodation ? (
                        <div className="mt-3 space-y-4">
                          {/* Venue selection */}
                          <RadioGroup
                            value={selectedVenueKey}
                            onValueChange={(value: string) => {
                              setSelectedVenueKey(value)
                              const venue = ACCOMMODATION_VENUES.find((v) => v.key === value)
                              if (venue?.options[0]) {
                                setAccommodationType(venue.options[0].id)
                              }
                            }}
                            className="space-y-2"
                          >
                            {ACCOMMODATION_VENUES.map((venue) => (
                              <div key={venue.key} className="flex items-center space-x-2">
                                <RadioGroupItem value={venue.key} id={`venue-${venue.key}`} />
                                <Label htmlFor={`venue-${venue.key}`} className="font-medium cursor-pointer text-sm">
                                  {venue.name}
                                </Label>
                              </div>
                            ))}
                          </RadioGroup>

                          {/* Sub-options for selected venue */}
                          {ACCOMMODATION_VENUES.filter((v) => v.key === selectedVenueKey).map((venue) => (
                            <div key={venue.key} className="pl-6 border-l-2 border-primary/20">
                              <p className="text-xs text-muted-foreground mb-2">
                                {venue.description}
                              </p>
                              <RadioGroup
                                value={accommodationType}
                                onValueChange={setAccommodationType}
                                className="space-y-2"
                              >
                                {venue.options.map((opt) => (
                                  <div key={opt.id} className="flex items-center space-x-2">
                                    <RadioGroupItem value={opt.id} id={opt.id} />
                                    <Label htmlFor={opt.id} className="font-normal cursor-pointer text-sm">
                                      {opt.label} — €{opt.price.toFixed(2)} (€{opt.nightlyRate}/night)
                                    </Label>
                                  </div>
                                ))}
                              </RadioGroup>
                            </div>
                          ))}
                        </div>
                      ) : (
                        <p className="text-sm text-muted-foreground mt-1">
                          I&apos;ll arrange my own accommodation
                        </p>
                      )}
                    </div>
                  </div>
                </div>

                {includeAccommodation && (
                  <p className="text-xs text-muted-foreground bg-muted/50 rounded-lg p-3">
                    We&apos;ll follow up closer to the event to confirm room assignments and accommodation details.
                  </p>
                )}

                {/* Food */}
                <div className="py-4 border-b border-border">
                  <div className="flex items-start gap-3">
                    <Checkbox
                      id="include-food"
                      checked={wantFood}
                      onCheckedChange={(checked) => setWantFood(checked as boolean)}
                      className="mt-1"
                    />
                    <div className="flex-1">
                      <Label htmlFor="include-food" className="font-medium cursor-pointer">
                        I would like to include food
                      </Label>
                      <p className="text-sm text-muted-foreground mt-1">
                        More details and costs will be shared soon — checking this box registers your interest
                        so we can plan accordingly. Your dietary preferences from step 1 have been noted.
                      </p>
                    </div>
                  </div>
                </div>

                {/* Processing fee */}
                <div className="flex items-start justify-between py-3">
                  <div>
                    <div className="text-sm text-muted-foreground">Payment processing fee ({(PROCESSING_FEE_PERCENT * 100).toFixed(0)}%)</div>
                  </div>
                  <span className="text-sm text-muted-foreground whitespace-nowrap ml-4">€{processingFee.toFixed(2)}</span>
                </div>

                {/* Total */}
                <div className="flex justify-between items-center py-4 bg-primary/10 -mx-6 px-6 mt-4">
                  <div>
                    <div className="font-bold text-lg">Total Amount</div>
                    <div className="text-sm text-muted-foreground">
                      Ticket{includeAccommodation ? " + accommodation" : ""}
                    </div>
                  </div>
                  <span className="text-2xl font-bold text-primary">€{totalPrice.toFixed(2)}</span>
                </div>
              </div>
            </CardContent>
          </Card>

          {/* Payment Methods */}
          <div className="space-y-6">
            <Card>
              <CardHeader>
                <CardTitle>Payment Options</CardTitle>
                <CardDescription>Choose your preferred payment method</CardDescription>
              </CardHeader>
              <CardContent className="space-y-4">
                <form action="/api/create-checkout-session" method="POST">
                  <input type="hidden" name="registrationData" value={JSON.stringify(formData)} />
                  <input type="hidden" name="includeAccommodation" value={includeAccommodation ? "true" : "false"} />
                  <input type="hidden" name="accommodationType" value={accommodationType} />

                  <div className="space-y-4">
                    <p className="text-sm text-muted-foreground">
                      You'll be redirected to Mollie's secure checkout where you can pay by credit card,
                      SEPA bank transfer, iDEAL, PayPal, or other methods.
                    </p>

                    <div className="flex gap-3 pt-4">
                      <Button type="button" variant="outline" onClick={() => setStep("form")} className="flex-1">
                        Back to Form
                      </Button>
                      <Button type="submit" className="flex-1">
                        Proceed to Payment
                      </Button>
                    </div>
                  </div>
                </form>
              </CardContent>
            </Card>

            <div className="text-center text-sm text-muted-foreground">
              <p>
                All payments are processed securely through Mollie. You'll receive a confirmation email after successful
                payment.
              </p>
            </div>
          </div>
        </main>

        {/* Simplified Footer */}
        <footer className="py-8 px-4 border-t border-border">
          <div className="container mx-auto max-w-6xl text-center text-sm text-muted-foreground">
            <p>
              {EVENT_FULL_NAME} · {EVENT_DATES} · {EVENT_LOCATION}
            </p>
            <p className="mt-2">
              <a href={LINKS.website} className="hover:text-foreground transition-colors">
                {LINKS.website.replace("https://", "")}
              </a>
              {" · "}
              <a href={`mailto:${LINKS.contactEmail}`} className="hover:text-foreground transition-colors">
                {LINKS.contactEmail}
              </a>
            </p>
          </div>
        </footer>
      </div>
    )
  }

  return (
    <div className="min-h-screen bg-background">
      {/* Header */}
      <header className="border-b">
        <div className="container mx-auto px-4 py-4">
          <Link href={LINKS.website} className="text-2xl font-bold text-primary">
            {EVENT_SHORT}
          </Link>
        </div>
      </header>

      <main className="container mx-auto px-4 py-12 max-w-3xl">
        <div className="text-center mb-12">
          <h1 className="text-4xl md:text-5xl font-bold mb-4">Register for {EVENT_SHORT}</h1>
          <p className="text-xl text-muted-foreground">{EVENT_DATES} · {EVENT_LOCATION}</p>
        </div>

        <Card>
          <CardHeader>
            <CardTitle>Registration Form</CardTitle>
            <CardDescription>Tell us about yourself and what you'd like to bring to {EVENT_SHORT}</CardDescription>
          </CardHeader>
          <CardContent>
            <form onSubmit={handleSubmit} className="space-y-6">
              {/* Name */}
              <div className="space-y-2">
                <Label htmlFor="name">What's your name? *</Label>
                <Input
                  id="name"
                  required
                  value={formData.name}
                  onChange={(e) => setFormData({ ...formData, name: e.target.value })}
                />
              </div>

              {/* Email */}
              <div className="space-y-2">
                <Label htmlFor="email">Email address *</Label>
                <Input
                  id="email"
                  type="email"
                  required
                  placeholder="your@email.com"
                  value={formData.email}
                  onChange={(e) => setFormData({ ...formData, email: e.target.value })}
                />
                <p className="text-sm text-muted-foreground">
                  We&apos;ll send your registration confirmation and event updates here.
                </p>
              </div>

              {/* Contact */}
              <div className="space-y-2">
                <Label htmlFor="contact">How can we contact you besides via email? *</Label>
                <Input
                  id="contact"
                  required
                  placeholder="Telegram, Signal, phone, etc."
                  value={formData.contact}
                  onChange={(e) => setFormData({ ...formData, contact: e.target.value })}
                />
              </div>

              {/* Contributions */}
              <div className="space-y-2">
                <Label htmlFor="contributions">What do you want to contribute to {EVENT_SHORT}? *</Label>
                <Textarea
                  id="contributions"
                  required
                  placeholder="This could be a talk, workshop, research inquiry, prototype, game, performance, etc."
                  className="min-h-[120px]"
                  value={formData.contributions}
                  onChange={(e) => setFormData({ ...formData, contributions: e.target.value })}
                />
                <p className="text-sm text-muted-foreground">
                  This event is participant-driven — each attendee is invited to co-create the program.
                </p>
              </div>

              {/* Expectations */}
              <div className="space-y-2">
                <Label htmlFor="expectations">What do you expect to gain from participating? *</Label>
                <Textarea
                  id="expectations"
                  required
                  placeholder="What are you looking for in particular?"
                  className="min-h-[100px]"
                  value={formData.expectations}
                  onChange={(e) => setFormData({ ...formData, expectations: e.target.value })}
                />
              </div>

              {/* How heard */}
              <div className="space-y-2">
                <Label htmlFor="howHeard">How did you hear about {EVENT_SHORT}?</Label>
                <Input
                  id="howHeard"
                  placeholder="First timers: Did anyone recommend it to you?"
                  value={formData.howHeard}
                  onChange={(e) => setFormData({ ...formData, howHeard: e.target.value })}
                />
              </div>

              {/* Dietary Requirements */}
              <div className="space-y-3">
                <Label>Dietary Requirements</Label>
                <p className="text-sm text-muted-foreground">
                  Do you have any special dietary requirements?
                </p>
                <div className="space-y-2">
                  {["vegetarian", "vegan", "gluten free", "lactose free"].map((diet) => (
                    <div key={diet} className="flex items-center space-x-2">
                      <Checkbox
                        id={diet}
                        checked={formData.dietary.includes(diet)}
                        onCheckedChange={(checked) => handleDietaryChange(diet, checked as boolean)}
                      />
                      <Label htmlFor={diet} className="font-normal cursor-pointer">
                        {diet.charAt(0).toUpperCase() + diet.slice(1)}
                      </Label>
                    </div>
                  ))}
                  <div className="flex items-start space-x-2 mt-2">
                    <Checkbox
                      id="other"
                      checked={!!formData.dietaryOther}
                      onCheckedChange={(checked) => {
                        if (!checked) setFormData({ ...formData, dietaryOther: "" })
                      }}
                    />
                    <div className="flex-1">
                      <Label htmlFor="other" className="font-normal cursor-pointer">
                        Other:
                      </Label>
                      <Input
                        id="dietaryOther"
                        className="mt-1"
                        placeholder="Please specify..."
                        value={formData.dietaryOther}
                        onChange={(e) => setFormData({ ...formData, dietaryOther: e.target.value })}
                      />
                    </div>
                  </div>
                </div>
              </div>

              {/* Participation Consent */}
              <div className="space-y-3">
                <Label>Participation Commitment *</Label>
                <div className="bg-muted p-4 rounded-lg space-y-2 text-sm">
                  <p>
                    {EVENT_SHORT} is a collaborative event — participants co-create its program,
                    activities, and atmosphere together.
                  </p>
                  <p className="font-medium">
                    You will be expected to actively contribute to the event beyond just attending sessions.
                  </p>
                </div>
                <RadioGroup
                  required
                  value={formData.crewConsent}
                  onValueChange={(value) => setFormData({ ...formData, crewConsent: value })}
                >
                  <div className="flex items-center space-x-2">
                    <RadioGroupItem value="cant-wait" id="cant-wait" />
                    <Label htmlFor="cant-wait" className="font-normal cursor-pointer">
                      Can't wait
                    </Label>
                  </div>
                  <div className="flex items-center space-x-2">
                    <RadioGroupItem value="yes-please" id="yes-please" />
                    <Label htmlFor="yes-please" className="font-normal cursor-pointer">
                      Yes please, sign me up!
                    </Label>
                  </div>
                  <div className="flex items-center space-x-2">
                    <RadioGroupItem value="love-it" id="love-it" />
                    <Label htmlFor="love-it" className="font-normal cursor-pointer">
                      I love getting my hands dirty :D
                    </Label>
                  </div>
                </RadioGroup>
              </div>

              <div className="pt-4">
                <Button type="submit" className="w-full" size="lg" disabled={isSubmitting}>
                  {isSubmitting ? "Recording registration..." : "Continue to Payment"}
                </Button>
              </div>

              <div className="text-sm text-muted-foreground text-center">
                <p>
                  Questions? Contact us at{" "}
                  <a href={`mailto:${LINKS.contactEmail}`} className="text-primary hover:underline">
                    {LINKS.contactEmail}
                  </a>
                  {LINKS.telegram && (
                    <>
                      {" or on "}
                      <a href={LINKS.telegram} className="text-primary hover:underline">
                        Telegram
                      </a>
                    </>
                  )}
                </p>
              </div>
            </form>
          </CardContent>
        </Card>
      </main>

      {/* Simplified Footer */}
      <footer className="py-8 px-4 border-t border-border">
        <div className="container mx-auto max-w-6xl text-center text-sm text-muted-foreground">
          <p>
            {EVENT_FULL_NAME} · {EVENT_DATES} · {EVENT_LOCATION}
          </p>
          <p className="mt-2">
            <a href={LINKS.website} className="hover:text-foreground transition-colors">
              {LINKS.website.replace("https://", "")}
            </a>
            {" · "}
            <a href={`mailto:${LINKS.contactEmail}`} className="hover:text-foreground transition-colors">
              {LINKS.contactEmail}
            </a>
          </p>
        </div>
      </footer>
    </div>
  )
}