import SwiftUI

// MARK: - 内容输入和预览组件
struct CodeContentInputView: View {
    let selectedDataType: DataType
    let selectedBarcodeType: BarcodeType
    let selectedQRCodeType: QRCodeType
    
    @Binding var content: String
    @Binding var validationResult: BarcodeValidator.ValidationResult?
    @FocusState.Binding var isContentFieldFocused: Bool
    
    var body: some View {
        VStack(spacing: 16) {
            // 内容输入区域
            contentInputSection
            
            // 预览区域
            if !content.isEmpty {
                previewSection
            }
        }
    }
    
    // MARK: - 内容输入区域
    private var contentInputSection: some View {
        Section("内容") {
            VStack(alignment: .leading, spacing: 12) {
                // 输入框和计数布局
                VStack(alignment: .trailing, spacing: 4) {
                    // 条形码格式提示
                    if selectedDataType == .barcode {
                        HStack {
                            Image(systemName: "info.circle")
                                .font(.caption)
                                .foregroundColor(.blue)
                            
                            Text(getBarcodeFormatHint())
                                .font(.caption)
                                .foregroundColor(.secondary)
                                .lineLimit(2)
                            
                            Spacer()
                        }
                        .padding(.horizontal, 4)
                        .padding(.vertical, 6)
                        .background(
                            RoundedRectangle(cornerRadius: 6)
                                .fill(Color.blue.opacity(0.1))
                        )
                    }
                    
                    TextField(getPlaceholderText(), text: $content)
                        .textFieldStyle(RoundedBorderTextFieldStyle())
                        .keyboardType(getKeyboardType())
                        .textInputAutocapitalization(getAutocapitalization())
                        .disableAutocorrection(true)
                        .focused($isContentFieldFocused)
                        .toolbar {
                            ToolbarItemGroup(placement: .keyboard) {
                                Spacer()
                                Button("完成") {
                                    isContentFieldFocused = false
                                }
                                .foregroundColor(.blue)
                                .font(.system(size: 16, weight: .medium))
                            }
                        }
                        .foregroundColor(.black)
                        .onChange(of: content) { newValue in
                            handleContentChange(newValue)
                        }
                    
                    // 计数显示在输入框下方，右对齐
                    if let maxLen = getMaxLength(), selectedDataType == .barcode {
                        Text("\(normalizedInputCount())/\(maxLen)")
                            .font(.caption2)
                            .foregroundColor(.blue)
                            .fontWeight(.medium)
                    }
                }
                
                // 输入统计与验证状态
                HStack {
                    if let result = validationResult, result.isValid {
                        Text("✓ 格式正确")
                            .font(.caption2)
                            .foregroundColor(.green)
                    } else if !content.isEmpty {
                        Text("⚠ 格式检查中...")
                            .font(.caption2)
                            .foregroundColor(.orange)
                    }
                }
                
                // 条形码验证信息（仅在格式不正确时显示）
                if selectedDataType == .barcode && !content.isEmpty && (validationResult == nil || !validationResult!.isValid) {
                    BarcodeValidationInfoView(
                        validationResult: validationResult,
                        barcodeType: selectedBarcodeType
                    )
                }
            }
        }
    }
    
    // MARK: - 预览区域
    private var previewSection: some View {
        Section("预览") {
            VStack(alignment: .leading, spacing: 12) {
                HStack {
                    Image(systemName: selectedDataType.icon)
                    Text(selectedDataType.displayName)
                    Spacer()
                    if selectedDataType == .barcode {
                        Text(selectedBarcodeType.displayName)
                            .font(.caption)
                            .padding(.horizontal, 8)
                            .padding(.vertical, 2)
                            .background(Color.green.opacity(0.1))
                            .foregroundColor(.green)
                            .cornerRadius(8)
                    } else {
                        Text(selectedQRCodeType.displayName)
                            .font(.caption)
                            .padding(.horizontal, 8)
                            .padding(.vertical, 2)
                            .background(Color.orange.opacity(0.1))
                            .foregroundColor(.orange)
                            .cornerRadius(8)
                    }
                }
                
                if selectedDataType == .barcode && !content.isEmpty && isInputComplete() {
                    // 条形码图片预览（仅在输入完成时显示）
                    BarcodePreviewView(
                        content: content,
                        barcodeType: selectedBarcodeType
                    )
                    .frame(height: 120)
                    .frame(maxWidth: .infinity)
                } else {
                    // 二维码或文本预览
                    Text(content)
                        .font(.body)
                        .foregroundColor(.secondary)
                        .padding()
                        .frame(maxWidth: .infinity, alignment: .leading)
                }
            }
            .padding()
            .background(Color(.systemGray6))
            .cornerRadius(8)
        }
    }
    
    // MARK: - 辅助方法
    
    private func handleContentChange(_ newValue: String) {
        // 针对有固定长度与数字要求的类型，进行输入规范化（仅保留数字并按最大长度截断）
        if selectedDataType == .barcode, let maxLen = getMaxLength(), requiresDigitsOnly() {
            let digits = newValue.filter { $0.isNumber }
            let truncated = String(digits.prefix(maxLen))
            if truncated != newValue {
                content = truncated
                // 播放输入提示音
                playInputSound()
            }
        } else if selectedDataType == .barcode {
            // 播放输入提示音
            playInputSound()
        }
        validateBarcodeContent(content)
    }
    
    private func validateBarcodeContent(_ newContent: String) {
        guard selectedDataType == .barcode else { return }
        validationResult = BarcodeValidator.validateBarcode(newContent, type: selectedBarcodeType)
    }
    
    private func getKeyboardType() -> UIKeyboardType {
        guard selectedDataType == .barcode else { return .default }
        switch selectedBarcodeType {
        case .ean13, .ean8, .upce, .itf14:
            return .numberPad
        case .code39, .code128, .pdf417:
            return .asciiCapable
        }
    }
    
    private func getAutocapitalization() -> TextInputAutocapitalization {
        guard selectedDataType == .barcode else { return .sentences }
        switch selectedBarcodeType {
        case .ean13, .ean8, .upce, .itf14:
            return .never
        case .code39, .code128, .pdf417:
            return .characters
        }
    }
    
    private func getMaxLength() -> Int? {
        guard selectedDataType == .barcode else { return nil }
        switch selectedBarcodeType {
        case .ean13: return 13
        case .ean8: return 8
        case .upce: return 8
        case .itf14: return 14
        default: return nil
        }
    }
    
    private func requiresDigitsOnly() -> Bool {
        guard selectedDataType == .barcode else { return false }
        switch selectedBarcodeType {
        case .ean13, .ean8, .upce, .itf14:
            return true
        default:
            return false
        }
    }
    
    private func normalizedInputCount() -> Int {
        if requiresDigitsOnly() {
            return content.filter { $0.isNumber }.count
        }
        return content.count
    }
    
    private func getBarcodeFormatHint() -> String {
        switch selectedBarcodeType {
        case .ean13:
            return "请输入13位数字，如：1234567890123"
        case .ean8:
            return "请输入8位数字，如：12345678"
        case .upce:
            return "请输入8位数字，如：12345678"
        case .code39:
            return "请输入字母、数字、空格和特殊字符"
        case .code128:
            return "请输入任意ASCII字符"
        case .itf14:
            return "请输入14位数字，如：12345678901234"
        case .pdf417:
            return "请输入任意ASCII字符"
        }
    }
    
    private func getPlaceholderText() -> String {
        if selectedDataType == .barcode {
            switch selectedBarcodeType {
            case .ean13:
                return "输入13位数字"
            case .ean8:
                return "输入8位数字"
            case .upce:
                return "输入8位数字"
            case .code39:
                return "输入字母、数字等"
            case .code128:
                return "输入任意字符"
            case .itf14:
                return "输入14位数字"
            case .pdf417:
                return "输入任意字符"
            }
        } else {
            return "请输入内容"
        }
    }
    
    private func playInputSound() {
        // 使用系统触觉反馈作为输入提示音
        let impactFeedback = UIImpactFeedbackGenerator(style: .light)
        impactFeedback.impactOccurred()
    }
    
    private func isInputComplete() -> Bool {
        if selectedDataType == .barcode {
            // 条形码需要验证格式正确
            return validationResult?.isValid == true
        } else {
            // 二维码只要有内容就算完成
            return !content.isEmpty
        }
    }
}