"use client";

import * as React from "react";
import { useState, useMemo, useEffect, useRef } from "react";
import { motion } from "framer-motion";
import * as confetti from "canvas-confetti";
import {
  Layers,
  BrainCircuit,
  Workflow,
  Plug,
  CheckCircle2,
  AlertCircle,
} from "lucide-react";

import { useAnalytics } from "./analytics/useAnalytics";
import { AnalyticsEvents } from "./analytics/analytics-events";

import { FormState } from "./ContactForm/types";
import {
  PRICING,
  initialState,
  FEATURE_OPTIONS,
  FUNCTION_OPTIONS,
  API_OPTIONS,
  PAGE_SAMPLES,
  ASSET_OPTIONS,
} from "./ContactForm/constants";
import { calculateTotals } from "@mintel/pdf";
import { sendContactInquiry } from "../actions/contact";

// Configurator Components
import { ConfiguratorLayout } from "./ContactForm/Configurator/ConfiguratorLayout";
import { NarrativeInput } from "./ContactForm/Configurator/NarrativeInput";
import { ModuleGrid } from "./ContactForm/Configurator/ModuleGrid";
import { ReferenceInput } from "./ContactForm/Configurator/ReferenceInput";
import { Launchpad } from "./ContactForm/Configurator/Launchpad";
import { Reveal } from "./Reveal";

interface ContactFormProps {
  initialStepIndex?: number;
  initialState?: Partial<FormState>;
}

const CONFIGURATOR_STEPS = [
  { id: "intro", title: "INITIALISIERUNG" },
  { id: "scope", title: "PROJEKT_UMFANG" },
  { id: "refs", title: "INSPIRATIONS_QUELLE" },
  { id: "assets", title: "BESTANDS_AUFNAHME" },
  { id: "features", title: "KERN_MODULE" },
  { id: "functions", title: "FUNKTIONALE_ERW" },
  { id: "api", title: "SYSTEM_INTEGRATION" },
  { id: "launch", title: "FINALE_SEQUENZ" },
];

import { ContactGateway } from "./ContactForm/ContactGateway";
import { DirectMessageFlow } from "./ContactForm/DirectMessageFlow";

type FlowState = "discovery" | "configurator" | "direct-message";

export function ContactForm({
  initialStepIndex = 0,
  initialState: injectedState,
}: ContactFormProps) {
  const [flow, setFlow] = useState<FlowState>("discovery");
  const [stepIndex, setStepIndex] = useState(initialStepIndex);
  const [state, setState] = useState<FormState>({
    ...initialState,
    ...injectedState,
  });
  const [isSubmitted, setIsSubmitted] = useState(false);
  const [isSubmitting, setIsSubmitting] = useState(false);
  const [error, setError] = useState<string | null>(null);

  const { trackEvent } = useAnalytics();

  const containerRef = useRef<HTMLDivElement>(null);

  // Scroll to top on flow or step change
  useEffect(() => {
    if (containerRef.current) {
      containerRef.current.scrollTo({ top: 0, behavior: "smooth" });
    } else {
      window.scrollTo({ top: 0, behavior: "smooth" });
    }
  }, [flow, stepIndex]);

  // Keyboard Navigation (only for configurator)
  useEffect(() => {
    if (flow !== "configurator") return;
    const handleKeyDown = (e: KeyboardEvent) => {
      if (
        e.target instanceof HTMLInputElement ||
        e.target instanceof HTMLTextAreaElement
      )
        return;
      if (e.key === "Enter" && stepIndex < CONFIGURATOR_STEPS.length - 1) {
        handleNext();
      } else if (e.key === "Backspace" && stepIndex > 0) {
        handlePrev();
      }
    };
    window.addEventListener("keydown", handleKeyDown);
    return () => window.removeEventListener("keydown", handleKeyDown);
  }, [stepIndex, flow]);

  const totals = useMemo(() => calculateTotals(state as any, PRICING), [state]);

  const updateState = (updates: Partial<FormState>) => {
    setState((prev) => ({ ...prev, ...updates }));
  };

  const toggleItem = (list: string[], id: string) => {
    return list.includes(id) ? list.filter((i) => i !== id) : [...list, id];
  };

  const handleNext = () => setStepIndex((prev) => prev + 1);
  const handlePrev = () => setStepIndex((prev) => Math.max(0, prev - 1));

  const handleSubmit = async (e?: React.FormEvent) => {
    e?.preventDefault();
    setIsSubmitting(true);
    setError(null);

    const result = await sendContactInquiry({
      name: state.name,
      email: state.email,
      companyName: state.companyName,
      projectType: state.projectType,
      message: state.message,
      isFreeText: flow === "direct-message",
      config: flow === "configurator" ? state : undefined,
    });

    setIsSubmitting(false);

    if (result.success) {
      setIsSubmitted(true);
      trackEvent(AnalyticsEvents.CONTACT_FORM_SUBMIT, {
        flow,
        config: flow === "configurator" ? state : undefined,
      });
      // Celebration
      const duration = 3 * 1000;
      const animationEnd = Date.now() + duration;
      const defaults = { startVelocity: 30, spread: 360, ticks: 60, zIndex: 0 };
      const randomInRange = (min: number, max: number) =>
        Math.random() * (max - min) + min;

      const interval: any = setInterval(function () {
        const timeLeft = animationEnd - Date.now();
        if (timeLeft <= 0) return clearInterval(interval);
        const particleCount = 50 * (timeLeft / duration);
        (confetti as any)({
          ...defaults,
          particleCount,
          origin: { x: randomInRange(0.1, 0.3), y: Math.random() - 0.2 },
        });
        (confetti as any)({
          ...defaults,
          particleCount,
          origin: { x: randomInRange(0.7, 0.9), y: Math.random() - 0.2 },
        });
      }, 250);
    } else {
      setError(result.error || "Unerwarteter Fehler bei der Übertragung.");
    }
  };

  // Success view (unified)
  if (isSubmitted) {
    return (
      <div className="w-full min-h-[50vh] bg-white flex flex-col items-center justify-center p-8 text-center space-y-8 z-50 rounded-xl border border-slate-100 shadow-sm">
        <Reveal width="100%" delay={0.1}>
          <div className="flex flex-col items-center space-y-8">
            <motion.div
              initial={{ scale: 0 }}
              animate={{ scale: 1 }}
              transition={{ type: "spring" }}
              className="w-24 h-24 bg-green-500 rounded-full flex items-center justify-center text-slate-900 mb-4"
            >
              <CheckCircle2 size={48} />
            </motion.div>
            <h1 className="text-3xl md:text-5xl font-mono text-slate-900 tracking-widest">
              SEQUENZ_INITIIERT
            </h1>
            <p className="text-slate-600 font-mono">
              Das System wird Sie in Kürze unter {state.email} kontaktieren.
            </p>
            <button
              onClick={() => {
                setIsSubmitted(false);
                setFlow("discovery");
                setStepIndex(0);
                setState(initialState);
              }}
              className="mt-8 text-green-600 underline font-mono hover:text-green-800"
            >
              [ NEUE_SEQUENZ_STARTEN ]
            </button>
          </div>
        </Reveal>
      </div>
    );
  }

  // Gateway Flow
  if (flow === "discovery") {
    return (
      <ContactGateway
        name={state.name}
        setName={(v) => updateState({ name: v })}
        company={state.companyName}
        setCompany={(v) => updateState({ companyName: v })}
        projectType={state.projectType}
        setProjectType={(v) => updateState({ projectType: v })}
        onChooseConfigurator={() => setFlow("configurator")}
        onChooseDirectMessage={() => setFlow("direct-message")}
      />
    );
  }

  // Direct Message Flow
  if (flow === "direct-message") {
    return (
      <DirectMessageFlow
        name={state.name}
        email={state.email}
        setEmail={(v) => updateState({ email: v })}
        company={state.companyName}
        message={state.message}
        setMessage={(v) => updateState({ message: v })}
        onBack={() => setFlow("discovery")}
        onSubmit={handleSubmit}
        isSubmitting={isSubmitting}
      />
    );
  }

  // Configurator Flow
  const renderConfiguratorContent = () => {
    switch (CONFIGURATOR_STEPS[stepIndex].id) {
      case "intro":
        return (
          <NarrativeInput
            name={state.name}
            setName={(v) => updateState({ name: v })}
            company={state.companyName}
            setCompany={(v) => updateState({ companyName: v })}
            projectType={state.projectType}
            setProjectType={(v) => updateState({ projectType: v })}
          />
        );
      case "scope":
        return (
          <ModuleGrid
            title="SYSTEM MODULE"
            options={PAGE_SAMPLES.map((p) => ({
              id: p.id,
              title: p.label,
              description: p.desc,
              icon: <Layers size={20} />,
            }))}
            selected={state.selectedPages}
            onToggle={(id) =>
              updateState({
                selectedPages: toggleItem(state.selectedPages, id),
              })
            }
            otherCount={state.otherPagesCount}
            onOtherCountChange={(val) => updateState({ otherPagesCount: val })}
            otherLabel="Weitere Seiten"
          />
        );
      case "refs":
        return (
          <ReferenceInput
            references={state.references}
            setReferences={(refs) => updateState({ references: refs })}
          />
        );
      case "assets":
        return (
          <ModuleGrid
            title="VORHANDENE ASSETS"
            options={ASSET_OPTIONS.map((a) => ({
              id: a.id,
              title: a.label,
              description: a.desc,
              icon: <Layers size={20} />,
            }))}
            selected={state.assets}
            onToggle={(id) =>
              updateState({ assets: toggleItem(state.assets, id) })
            }
          />
        );
      case "features":
        return (
          <ModuleGrid
            title="KERN-FEATURES"
            options={FEATURE_OPTIONS.map((f) => ({
              id: f.id,
              title: f.label,
              description: f.desc,
              priceEstimate: "€€",
              icon: <BrainCircuit size={20} />,
            }))}
            selected={state.features}
            onToggle={(id) =>
              updateState({ features: toggleItem(state.features, id) })
            }
            otherCount={state.otherFeaturesCount}
            onOtherCountChange={(val) =>
              updateState({ otherFeaturesCount: val })
            }
            otherLabel="Zusätzliche Features"
          />
        );
      case "functions":
        return (
          <ModuleGrid
            title="ERWEITERTE FUNKTIONEN"
            options={FUNCTION_OPTIONS.map((f) => ({
              id: f.id,
              title: f.label,
              description: f.desc,
              priceEstimate: "€€€",
              icon: <Workflow size={20} />,
            }))}
            selected={state.functions}
            onToggle={(id) =>
              updateState({ functions: toggleItem(state.functions, id) })
            }
          />
        );
      case "api":
        return (
          <ModuleGrid
            title="SYSTEM-INTEGRATIONEN"
            options={API_OPTIONS.map((a) => ({
              id: a.id,
              title: a.label,
              description: a.desc,
              priceEstimate: "€€€",
              icon: <Plug size={20} />,
            }))}
            selected={state.apiSystems}
            onToggle={(id) =>
              updateState({ apiSystems: toggleItem(state.apiSystems, id) })
            }
          />
        );
      case "launch":
        return (
          <div className="space-y-6">
            {error && (
              <Reveal width="100%" direction="none">
                <div className="flex items-center gap-3 p-4 bg-red-50 text-red-700 rounded-xl border border-red-100 mb-6">
                  <AlertCircle size={20} />
                  <span className="text-sm font-bold uppercase tracking-wider">
                    {error}
                  </span>
                </div>
              </Reveal>
            )}
            <Launchpad
              email={state.email}
              setEmail={(v) => updateState({ email: v })}
              timeline={state.deadline}
              setTimeline={(v) => updateState({ deadline: v })}
              message={state.message}
              setMessage={(v) => updateState({ message: v })}
              onSubmit={handleSubmit}
              isValid={!!state.email && !!state.name}
            />
          </div>
        );
      default:
        return null;
    }
  };

  return (
    <div ref={containerRef} className="w-full h-full overflow-y-auto">
      <ConfiguratorLayout
        stepIndex={stepIndex}
        totalSteps={CONFIGURATOR_STEPS.length}
        title={CONFIGURATOR_STEPS[stepIndex].title}
        onNext={
          stepIndex < CONFIGURATOR_STEPS.length - 1 ? handleNext : undefined
        }
        onPrev={stepIndex > 0 ? handlePrev : undefined}
        isSubmitting={isSubmitting}
        totalPrice={totals.totalPrice}
        monthlyPrice={totals.monthlyPrice}
        onRestart={() => {
          setFlow("discovery");
          setStepIndex(0);
          setState(initialState);
        }}
      >
        {renderConfiguratorContent()}
      </ConfiguratorLayout>
    </div>
  );
}
