//
//  WordPuzzleView.swift
//  AIGrammar
//
//  Created by oscar on 2025/7/16.
//
import SwiftUI
import AVFoundation

struct WordPuzzleGameView: View {
    @State private var letters: [[String]] = []
    @State private var selectedLetters: [(Int, Int)] = []
    @State private var foundWords: [String] = []
    @State private var score: Int = 0
    @State private var remainingTime = 60
    @State private var isGameOver = false
    
    @GestureState private var dragLocation: CGPoint? = nil
    @State private var audioPlayer: AVAudioPlayer?

    let validWords = ["WORD", "GAME", "PUZZLE", "MET", "ME", "GO"]
    let gridSize = 4
    let timer = Timer.publish(every: 1, on: .main, in: .common).autoconnect()
    
    init() {
        var chars = Array("WORDPUZZLEGAMETO").map { String($0) }
        chars.shuffle()
        _letters = State(initialValue: stride(from: 0, to: chars.count, by: gridSize).map {
            Array(chars[$0..<$0+gridSize])
        })
    }
    
    var body: some View {
        VStack {
            Text("Time: \(remainingTime)s   Score: \(score)")
                .font(.headline)
            
            if isGameOver {
                Text("Game Over!")
                    .font(.largeTitle)
                    .foregroundColor(.red)
            } else {
                VStack(spacing: 4) {
                    ForEach(0..<gridSize, id: \.self) { row in
                        HStack(spacing: 4) {
                            ForEach(0..<gridSize, id: \.self) { col in
                                Text(letters[row][col])
                                    .font(.title)
                                    .frame(width: 50, height: 50)
                                    .background(
                                        selectedLetters.contains(where: { $0 == (row, col) }) ?
                                        Color.blue.opacity(0.7) : Color.gray.opacity(0.2)
                                    )
                                    .cornerRadius(8)
                                    .onTapGesture {
                                        handleSelect(row: row, col: col)
                                    }
                            }
                        }
                    }
                }
                .gesture(
                    DragGesture()
                        .updating($dragLocation) { value, state, _ in
                            state = value.location
                            selectLetter(at: value.location)
                        }
                        .onEnded { _ in
                            submitWord()
                        }
                )
            }

            ScrollView(.horizontal) {
                HStack {
                    ForEach(foundWords, id: \.self) { word in
                        Text(word)
                            .padding(6)
                            .background(Color.green.opacity(0.3))
                            .cornerRadius(6)
                    }
                }
                .padding()
            }
        }
        .padding()
        .onReceive(timer) { _ in
            guard !isGameOver else { return }
            if remainingTime > 0 {
                remainingTime -= 1
            } else {
                isGameOver = true
                timer.upstream.connect().cancel()
            }
        }
    }
    
    /// 点击选择
    private func handleSelect(row: Int, col: Int) {
        if !selectedLetters.contains(where: { $0 == (row, col) }) {
            selectedLetters.append((row, col))
        }
    }
    
    /// 拖动选择
    private func selectLetter(at point: CGPoint?) {
        guard let point = point else { return }
        for row in 0..<gridSize {
            for col in 0..<gridSize {
                let cellSize: CGFloat = 50 + 4
                let cellOrigin = CGPoint(x: CGFloat(col) * cellSize + 20,
                                         y: CGFloat(row) * cellSize + 120)
                let cellRect = CGRect(origin: cellOrigin, size: CGSize(width: 50, height: 50))
                if cellRect.contains(point) {
                    if !selectedLetters.contains(where: { $0 == (row, col) }) {
                        selectedLetters.append((row, col))
                    }
                }
            }
        }
    }
    
    /// 提交选中的单词
    private func submitWord() {
        let word = selectedLetters.map { letters[$0.0][$0.1] }.joined()
        
        if validWords.contains(word) && !foundWords.contains(word) {
            foundWords.append(word)
            score += word.count * 10
            playSound(named: "success")
        } else {
            playSound(named: "fail")
        }
        selectedLetters.removeAll()
    }
    
    /// 播放提示音
    private func playSound(named name: String) {
        guard let url = Bundle.main.url(forResource: name, withExtension: "mp3") else { return }
        audioPlayer = try? AVAudioPlayer(contentsOf: url)
        audioPlayer?.play()
    }
}

struct WordPuzzleGameView_Previews: PreviewProvider {
    static var previews: some View {
        WordPuzzleGameView()
    }
}

#Preview {
    WordPuzzleGameView()
}