'use client';

import { motion } from 'framer-motion';
import { User, Globe, Network, Server, Shield, ArrowDown, ArrowRight, CheckCircle } from 'lucide-react';

const steps = [
  {
    id: 1,
    title: 'User Request',
    description: 'User types domain',
    icon: User,
    color: 'blue',
  },
  {
    id: 2,
    title: 'DNS Query',
    description: 'P2NS DNS Server',
    icon: Globe,
    color: 'purple',
  },
  {
    id: 3,
    title: 'P2P Network',
    description: 'Find Domain Hash',
    icon: Network,
    color: 'green',
  },
  {
    id: 4,
    title: 'Virtual Interface',
    description: 'Assign Local IP',
    icon: Server,
    color: 'orange',
  },
  {
    id: 5,
    title: 'Holesail Client',
    description: 'Establish Tunnel',
    icon: Shield,
    color: 'red',
  },
  {
    id: 6,
    title: 'HTTPS Proxy',
    description: 'Route Request',
    icon: Server,
    color: 'indigo',
  },
  {
    id: 7,
    title: 'Service Response',
    description: 'Back to User',
    icon: CheckCircle,
    color: 'blue',
  },
];

const colorClasses = {
  blue: 'bg-blue-100 dark:bg-blue-900 text-blue-600 dark:text-blue-400 border-blue-200 dark:border-blue-700',
  purple: 'bg-purple-100 dark:bg-purple-900 text-purple-600 dark:text-purple-400 border-purple-200 dark:border-purple-700',
  green: 'bg-green-100 dark:bg-green-900 text-green-600 dark:text-green-400 border-green-200 dark:border-green-700',
  orange: 'bg-orange-100 dark:bg-orange-900 text-orange-600 dark:text-orange-400 border-orange-200 dark:border-orange-700',
  red: 'bg-red-100 dark:bg-red-900 text-red-600 dark:text-red-400 border-red-200 dark:border-red-700',
  indigo: 'bg-indigo-100 dark:bg-indigo-900 text-indigo-600 dark:text-indigo-400 border-indigo-200 dark:border-indigo-700',
};

export default function P2NSFlowDiagram() {
  // Group steps into rows of 2 (last row may have 1 item)
  const rows: (typeof steps)[] = [];
  for (let i = 0; i < steps.length; i += 2) {
    rows.push(steps.slice(i, i + 2));
  }

  return (
    <div className="bg-gradient-to-br from-gray-50 to-gray-100 dark:from-gray-800 dark:to-gray-900 rounded-xl p-6 md:p-8 border border-gray-200 dark:border-gray-700 shadow-lg">
      <div className="max-w-4xl mx-auto">
        {rows.map((row, rowIndex) => {
          const isLastRow = rowIndex === rows.length - 1;
          const isSingleItemRow = row.length === 1;

          return (
            <div key={rowIndex} className="flex flex-col items-center">
              {/* Use a centered single column for the very last step */}
              {isLastRow && isSingleItemRow ? (
                <div className="w-full flex justify-center">
                  <div className="max-w-md w-full">
                    {row.map((step) => {
                      const Icon = step.icon;
                      const globalIndex = steps.indexOf(step);

                      return (
                        <motion.div
                          key={step.id}
                          initial={{ opacity: 0, y: -10 }}
                          whileInView={{ opacity: 1, y: 0 }}
                          viewport={{ once: true }}
                          transition={{ duration: 0.4, delay: globalIndex * 0.08 }}
                          className="flex items-center gap-4 bg-white dark:bg-gray-800 rounded-xl p-4 shadow-md hover:shadow-lg border border-gray-200 dark:border-gray-700 transition-all duration-300 hover:scale-[1.02]"
                        >
                          <div className={`p-3 rounded-xl border-2 ${colorClasses[step.color as keyof typeof colorClasses]} shadow-sm flex-shrink-0 transition-all duration-300 hover:scale-110`}>
                            <Icon className="h-6 w-6" />
                          </div>
                          <div className="flex-1 min-w-0">
                            <h3 className="text-base font-bold text-gray-900 dark:text-white mb-1 leading-tight">
                              {step.title}
                            </h3>
                            <p className="text-sm text-gray-600 dark:text-gray-400 leading-snug">
                              {step.description}
                            </p>
                          </div>
                        </motion.div>
                      );
                    })}
                  </div>
                </div>
              ) : (
                /* Normal 2-column rows */
                <div className="grid grid-cols-1 md:grid-cols-2 gap-6 md:gap-8 w-full">
                  {row.map((step, stepIndex) => {
                    const Icon = step.icon;
                    const globalIndex = rowIndex * 2 + stepIndex;
                    const isLastInRow = stepIndex === row.length - 1;

                    return (
                      <div key={step.id} className="flex items-center">
                        <motion.div
                          initial={{ opacity: 0, y: -10 }}
                          whileInView={{ opacity: 1, y: 0 }}
                          viewport={{ once: true }}
                          transition={{ duration: 0.4, delay: globalIndex * 0.08 }}
                          className="flex items-center gap-4 flex-1 bg-white dark:bg-gray-800 rounded-xl p-4 shadow-md hover:shadow-lg border border-gray-200 dark:border-gray-700 transition-all duration-300 hover:scale-[1.02]"
                        >
                          <div className={`p-3 rounded-xl border-2 ${colorClasses[step.color as keyof typeof colorClasses]} shadow-sm flex-shrink-0 transition-all duration-300 hover:scale-110`}>
                            <Icon className="h-6 w-6" />
                          </div>
                          <div className="flex-1 min-w-0">
                            <h3 className="text-base font-bold text-gray-900 dark:text-white mb-1 leading-tight">
                              {step.title}
                            </h3>
                            <p className="text-sm text-gray-600 dark:text-gray-400 leading-snug">
                              {step.description}
                            </p>
                          </div>
                        </motion.div>

                        {!isLastInRow && (
                          <motion.div
                            initial={{ opacity: 0, scale: 0.8 }}
                            whileInView={{ opacity: 1, scale: 1 }}
                            viewport={{ once: true }}
                            transition={{ duration: 0.4, delay: globalIndex * 0.08 + 0.2 }}
                            className="flex-shrink-0 mx-4"
                          >
                            <ArrowRight className="h-5 w-5 text-gray-500 dark:text-gray-400" strokeWidth={2.5} />
                          </motion.div>
                        )}
                      </div>
                    );
                  })}
                </div>
              )}

              {/* Down arrow between rows */}
              {!isLastRow && (
                <motion.div
                  initial={{ opacity: 0, scale: 0.8 }}
                  whileInView={{ opacity: 1, scale: 1 }}
                  viewport={{ once: true }}
                  transition={{ duration: 0.4, delay: (rowIndex * 2 + 1) * 0.08 + 0.2 }}
                  className="my-6 md:my-8"
                >
                  <ArrowDown className="h-7 w-7 text-gray-500 dark:text-gray-400" strokeWidth={2.5} />
                </motion.div>
              )}
            </div>
          );
        })}
      </div>
    </div>
  );
}