'use client';

import { useEffect, useRef, useState } from 'react';

interface Skill {
  name: string;
  level: number; // 1-5
  category: string;
}

const skillsData: Skill[] = [
  // Programmiersprachen
  { name: 'PHP & FW Laravel', level: 4, category: 'Programmiersprachen' },
  { name: 'Python & Perl', level: 4, category: 'Programmiersprachen' },
  { name: 'JavaScript', level: 4, category: 'Programmiersprachen' },
  { name: 'Node.js', level: 3, category: 'Programmiersprachen' },
  { name: 'Vue.js / Next.js', level: 4, category: 'Programmiersprachen' },
  { name: 'HTML', level: 5, category: 'Programmiersprachen' },
  { name: 'CSS & Frameworks', level: 5, category: 'Programmiersprachen' },
  { name: 'Sass', level: 4, category: 'Programmiersprachen' },
  
  // Datenbanken
  { name: 'SQL (MS/DB2/Oracle)', level: 4, category: 'Datenbanken' },
  { name: 'MySQL, MariaDB, Postgres', level: 4, category: 'Datenbanken' },
  { name: 'Redis', level: 4, category: 'Datenbanken' },
  { name: 'MongoDB', level: 3, category: 'Datenbanken' },
  { name: 'CouchDB', level: 3, category: 'Datenbanken' },
  { name: 'Firebase', level: 1, category: 'Datenbanken' },
  
  // DevOps
  { name: 'Linux Bash Scripting', level: 4, category: 'DevOps' },
  { name: 'Git / SVN', level: 4, category: 'DevOps' },
  { name: 'Docker / Kubernetes', level: 3, category: 'DevOps' },
  { name: 'AWS', level: 3, category: 'DevOps' },
  { name: 'CI/CD Pipelines', level: 4, category: 'DevOps' },
  { name: 'Draw.io Architektur', level: 4, category: 'DevOps' },
  
  // Grafik & Design
  { name: 'Adobe Suite (u.a. PS/XD)', level: 4, category: 'Grafik & Design' },
  { name: 'Affinity', level: 4, category: 'Grafik & Design' },
  { name: 'FinalCut', level: 4, category: 'Grafik & Design' },
];

const categories = [
  'Programmiersprachen',
  'Datenbanken',
  'DevOps',
  'Grafik & Design',
];

export default function Skills() {
  const [activeCategory, setActiveCategory] = useState<string>('Programmiersprachen');
  const [isVisible, setIsVisible] = useState(false);
  const ref = useRef<HTMLElement>(null);

  useEffect(() => {
    const currentRef = ref.current;
    const observer = new IntersectionObserver(
      ([entry]) => {
        if (entry.isIntersecting) {
          setIsVisible(true);
        }
      },
      { threshold: 0.1 }
    );

    if (currentRef) {
      observer.observe(currentRef);
    }

    return () => {
      if (currentRef) {
        observer.unobserve(currentRef);
      }
    };
  }, []);

  const filteredSkills = skillsData.filter((skill) => skill.category === activeCategory);

  return (
    <section
      id="skills"
      ref={ref}
      className={`py-20 px-4 sm:px-6 lg:px-8 bg-gradient-to-br from-bg-light to-white transition-opacity duration-1000 ${
        isVisible ? 'opacity-100' : 'opacity-0'
      }`}
    >
      <div className="max-w-6xl mx-auto">
        <h2 className="text-3xl sm:text-4xl font-bold text-text text-center mb-4 relative inline-block w-full">
          Technische Fähigkeiten
        </h2>
        <p className="text-center text-text-light mb-12 max-w-2xl mx-auto">
          Umfassende Expertise in modernen Technologien und Frameworks
        </p>

        {/* Category Tabs */}
        <div className="flex flex-wrap justify-center gap-3 mb-12">
          {categories.map((category, index) => (
            <button
              key={category}
              onClick={() => setActiveCategory(category)}
              className={`px-5 py-3 rounded-lg font-semibold text-sm transition-all duration-300 ${
                activeCategory === category
                  ? 'bg-primary text-white shadow-lg scale-105'
                  : 'bg-white text-text-light hover:bg-gray-100 hover:text-text shadow-md'
              } ${isVisible ? 'animate-fade-in' : 'opacity-0'}`}
              style={{ animationDelay: `${index * 50}ms` }}
            >
              {category}
            </button>
          ))}
        </div>

        {/* Skills Grid */}
        <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-3 gap-6">
          {filteredSkills.map((skill, index) => (
            <div
              key={skill.name}
              className={`bg-white rounded-lg p-6 shadow-md hover:shadow-xl transition-all duration-300 hover:-translate-y-1 ${
                isVisible ? 'animate-fade-in' : 'opacity-0'
              }`}
              style={{ animationDelay: `${(index + categories.length) * 50}ms` }}
            >
              {/* Skill Name */}
              <h3 className="font-bold text-text mb-3 text-base">{skill.name}</h3>

              {/* Level Bar */}
              <div className="flex items-center gap-2">
                <div className="flex-1 bg-gray-200 rounded-full h-2.5 overflow-hidden">
                  <div
                    className="bg-gradient-to-r from-primary to-primary-dark h-full rounded-full transition-all duration-1000 ease-out"
                    style={{
                      width: isVisible ? `${(skill.level / 5) * 100}%` : '0%',
                      transitionDelay: `${(index + categories.length) * 50 + 200}ms`,
                    }}
                  />
                </div>
                <span className="text-sm font-bold text-primary min-w-[2rem] text-right">
                  {skill.level}/5
                </span>
              </div>

              {/* Level Dots */}
              <div className="flex gap-1 mt-3">
                {[1, 2, 3, 4, 5].map((dot) => (
                  <div
                    key={dot}
                    className={`w-2 h-2 rounded-full transition-all duration-300 ${
                      dot <= skill.level ? 'bg-primary' : 'bg-gray-300'
                    }`}
                    style={{
                      transitionDelay: `${(index + categories.length) * 50 + dot * 50}ms`,
                    }}
                  />
                ))}
              </div>
            </div>
          ))}
        </div>

        {/* Info Text */}
        <div className="mt-12 text-center">
          <p className="text-text-light text-sm">
            <strong className="text-primary">Bewertungsskala:</strong> 1 = Grundkenntnisse | 5 = Expertenwissen
          </p>
        </div>
      </div>
    </section>
  );
}