"use client";

import React, { useState, useEffect } from 'react';
import { useRouter } from 'next/navigation';
import { motion, AnimatePresence } from 'framer-motion';
import { Button } from '@/components/ui/button';
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card';
import { Progress } from '@/components/ui/progress';
import { CheckCircle, ArrowRight, ArrowLeft, Bot, Sparkles, Zap, Brain } from 'lucide-react';
import { Logo } from '@/components/Logo';
import { useLLMConfigs, useLLMPreferences } from '@/hooks/use-llm-configs';
import { AddProviderStep } from '@/components/onboard/add-provider-step';
import { AssignRolesStep } from '@/components/onboard/assign-roles-step';
import { CompletionStep } from '@/components/onboard/completion-step';

const TOTAL_STEPS = 3;

const OnboardPage = () => {
  const router = useRouter();
  const { llmConfigs, loading: configsLoading, refreshConfigs } = useLLMConfigs();
  const { preferences, loading: preferencesLoading, isOnboardingComplete, refreshPreferences } = useLLMPreferences();
  const [currentStep, setCurrentStep] = useState(1);
  const [hasUserProgressed, setHasUserProgressed] = useState(false);

  // Check if user is authenticated
  useEffect(() => {
    const token = localStorage.getItem('surfsense_bearer_token');
    if (!token) {
      router.push('/login');
      return;
    }
  }, [router]);

  // Track if user has progressed beyond step 1
  useEffect(() => {
    if (currentStep > 1) {
      setHasUserProgressed(true);
    }
  }, [currentStep]);

  // Redirect to dashboard if onboarding is already complete and user hasn't progressed (fresh page load)
  useEffect(() => {
    if (!preferencesLoading && isOnboardingComplete() && !hasUserProgressed) {
      router.push('/dashboard');
    }
  }, [preferencesLoading, isOnboardingComplete, hasUserProgressed, router]);



  const progress = (currentStep / TOTAL_STEPS) * 100;

  const stepTitles = [
    "Add LLM Provider",
    "Assign LLM Roles", 
    "Setup Complete"
  ];

  const stepDescriptions = [
    "Configure your first model provider",
    "Assign specific roles to your LLM configurations",
    "You're all set to start using SurfSense!"
  ];

  const canProceedToStep2 = !configsLoading && llmConfigs.length > 0;
  const canProceedToStep3 = !preferencesLoading && preferences.long_context_llm_id && preferences.fast_llm_id && preferences.strategic_llm_id;
  


  const handleNext = () => {
    if (currentStep < TOTAL_STEPS) {
      setCurrentStep(currentStep + 1);
    }
  };

  const handlePrevious = () => {
    if (currentStep > 1) {
      setCurrentStep(currentStep - 1);
    }
  };

  const handleComplete = () => {
    router.push('/dashboard');
  };

  if (configsLoading || preferencesLoading) {
    return (
      <div className="flex flex-col items-center justify-center min-h-screen">
        <Card className="w-[350px] bg-background/60 backdrop-blur-sm">
          <CardContent className="flex flex-col items-center justify-center py-12">
            <Bot className="h-12 w-12 text-primary animate-pulse mb-4" />
            <p className="text-sm text-muted-foreground">Loading your configuration...</p>
          </CardContent>
        </Card>
      </div>
    );
  }

  return (
    <div className="min-h-screen bg-gradient-to-br from-background via-background to-muted/20 flex items-center justify-center p-4">
      <motion.div
        initial={{ opacity: 0, y: 20 }}
        animate={{ opacity: 1, y: 0 }}
        transition={{ duration: 0.5 }}
        className="w-full max-w-4xl"
      >
        {/* Header */}
        <div className="text-center mb-8">
          <div className="flex items-center justify-center mb-4">
            <Logo className="w-12 h-12 mr-3" />
            <h1 className="text-3xl font-bold">Welcome to SurfSense</h1>
          </div>
          <p className="text-muted-foreground text-lg">Let's configure your SurfSense to get started</p>
        </div>

        {/* Progress */}
        <Card className="mb-8 bg-background/60 backdrop-blur-sm">
          <CardContent className="pt-6">
            <div className="flex items-center justify-between mb-4">
              <div className="text-sm font-medium">Step {currentStep} of {TOTAL_STEPS}</div>
              <div className="text-sm text-muted-foreground">{Math.round(progress)}% Complete</div>
            </div>
            <Progress value={progress} className="mb-4" />
            <div className="grid grid-cols-3 gap-4">
              {Array.from({ length: TOTAL_STEPS }, (_, i) => {
                const stepNum = i + 1;
                const isCompleted = stepNum < currentStep;
                const isCurrent = stepNum === currentStep;
                
                return (
                  <div key={stepNum} className="flex items-center space-x-2">
                    <div className={`w-8 h-8 rounded-full flex items-center justify-center text-sm font-medium ${
                      isCompleted 
                        ? 'bg-primary text-primary-foreground' 
                        : isCurrent 
                          ? 'bg-primary/20 text-primary border-2 border-primary' 
                          : 'bg-muted text-muted-foreground'
                    }`}>
                      {isCompleted ? <CheckCircle className="w-4 h-4" /> : stepNum}
                    </div>
                    <div className="flex-1 min-w-0">
                      <p className={`text-sm font-medium truncate ${
                        isCurrent ? 'text-foreground' : 'text-muted-foreground'
                      }`}>
                        {stepTitles[i]}
                      </p>
                    </div>
                  </div>
                );
              })}
            </div>
          </CardContent>
        </Card>

        {/* Step Content */}
        <Card className="min-h-[500px] bg-background/60 backdrop-blur-sm">
          <CardHeader className="text-center">
            <CardTitle className="text-2xl flex items-center justify-center gap-2">
              {currentStep === 1 && <Bot className="w-6 h-6" />}
              {currentStep === 2 && <Sparkles className="w-6 h-6" />}
              {currentStep === 3 && <CheckCircle className="w-6 h-6" />}
              {stepTitles[currentStep - 1]}
            </CardTitle>
            <CardDescription className="text-base">
              {stepDescriptions[currentStep - 1]}
            </CardDescription>
          </CardHeader>
          <CardContent>
            <AnimatePresence mode="wait">
              <motion.div
                key={currentStep}
                initial={{ opacity: 0, x: 20 }}
                animate={{ opacity: 1, x: 0 }}
                exit={{ opacity: 0, x: -20 }}
                transition={{ duration: 0.3 }}
              >
                {currentStep === 1 && <AddProviderStep onConfigCreated={refreshConfigs} onConfigDeleted={refreshConfigs} />}
                {currentStep === 2 && <AssignRolesStep onPreferencesUpdated={refreshPreferences} />}
                {currentStep === 3 && <CompletionStep />}
              </motion.div>
            </AnimatePresence>
          </CardContent>
        </Card>

        {/* Navigation */}
        <div className="flex justify-between mt-8">
          <Button
            variant="outline"
            onClick={handlePrevious}
            disabled={currentStep === 1}
            className="flex items-center gap-2"
          >
            <ArrowLeft className="w-4 h-4" />
            Previous
          </Button>
          
          <div className="flex gap-2">
            {currentStep < TOTAL_STEPS && (
              <Button
                onClick={handleNext}
                disabled={
                  (currentStep === 1 && !canProceedToStep2) ||
                  (currentStep === 2 && !canProceedToStep3)
                }
                className="flex items-center gap-2"
              >
                Next
                <ArrowRight className="w-4 h-4" />
              </Button>
            )}
            
            {currentStep === TOTAL_STEPS && (
              <Button
                onClick={handleComplete}
                className="flex items-center gap-2"
              >
                Complete Setup
                <CheckCircle className="w-4 h-4" />
              </Button>
            )}
          </div>
        </div>
      </motion.div>
    </div>
  );
};

export default OnboardPage;