// SecureInput.swift
// iOS UI Components - Form Components
//
// Secure password input with reveal toggle

import SwiftUI
import LilithDesignTokens

/// Secure text input for passwords
///
/// Password field with show/hide toggle.
///
/// Example:
/// ```swift
/// @State private var password = ""
///
/// SecureInput("Password", text: $password)
/// ```
public struct SecureInput: View {
    // MARK: - Properties

    private let label: String
    @Binding private var text: String
    private let placeholder: String
    private let errorMessage: String?
    private let helperText: String?
    private let isDisabled: Bool
    private let onCommit: (() -> Void)?

    // MARK: - State

    @State private var isSecure = true
    @FocusState private var isFocused: Bool

    // MARK: - Initialization

    public init(
        _ label: String,
        text: Binding<String>,
        placeholder: String = "",
        errorMessage: String? = nil,
        helperText: String? = nil,
        isDisabled: Bool = false,
        onCommit: (() -> Void)? = nil
    ) {
        self.label = label
        self._text = text
        self.placeholder = placeholder
        self.errorMessage = errorMessage
        self.helperText = helperText
        self.isDisabled = isDisabled
        self.onCommit = onCommit
    }

    // MARK: - Body

    public var body: some View {
        VStack(alignment: .leading, spacing: AppSpacing.xs) {
            // Label
            Text(label)
                .font(AppTypography.label(weight: .medium))
                .foregroundColor(labelColor)

            // Input container
            HStack(spacing: AppSpacing.sm) {
                Image(systemName: "lock")
                    .font(.system(size: AppTypography.FontSize.base))
                    .foregroundColor(iconColor)

                if isSecure {
                    SecureField(placeholder, text: $text)
                        .font(AppTypography.body())
                        .foregroundColor(AppColors.textPrimary)
                        .disabled(isDisabled)
                        .focused($isFocused)
                        .onSubmit {
                            onCommit?()
                        }
                } else {
                    TextField(placeholder, text: $text)
                        .font(AppTypography.body())
                        .foregroundColor(AppColors.textPrimary)
                        .disabled(isDisabled)
                        .focused($isFocused)
                        .onSubmit {
                            onCommit?()
                        }
                }

                // Show/hide toggle
                Button(action: { isSecure.toggle() }) {
                    Image(systemName: isSecure ? "eye" : "eye.slash")
                        .font(.system(size: AppTypography.FontSize.base))
                        .foregroundColor(AppColors.textSecondary)
                }
            }
            .padding(.horizontal, AppSpacing.md)
            .padding(.vertical, AppSpacing.sm)
            .background(backgroundColor)
            .overlay(
                RoundedRectangle(cornerRadius: AppRadius.input)
                    .stroke(borderColor, lineWidth: isFocused ? 2 : 1)
            )
            .clipShape(RoundedRectangle(cornerRadius: AppRadius.input))

            // Helper or error text
            if let errorMessage = errorMessage {
                Text(errorMessage)
                    .font(AppTypography.caption())
                    .foregroundColor(AppColors.Semantic.error)
            } else if let helperText = helperText {
                Text(helperText)
                    .font(AppTypography.caption())
                    .foregroundColor(AppColors.textSecondary)
            }
        }
        .animation(AppAnimations.fast, value: isFocused)
        .animation(AppAnimations.fast, value: errorMessage)
    }

    // MARK: - Computed Properties

    private var labelColor: Color {
        if isDisabled {
            return AppColors.textTertiary
        }
        if errorMessage != nil {
            return AppColors.Semantic.error
        }
        if isFocused {
            return AppColors.primary
        }
        return AppColors.textSecondary
    }

    private var borderColor: Color {
        if isDisabled {
            return AppColors.Gray.gray700
        }
        if errorMessage != nil {
            return AppColors.Semantic.error
        }
        if isFocused {
            return AppColors.primary
        }
        return AppColors.border
    }

    private var backgroundColor: Color {
        isDisabled ? AppColors.Gray.gray800 : AppColors.surface
    }

    private var iconColor: Color {
        if isDisabled {
            return AppColors.textTertiary
        }
        if isFocused {
            return AppColors.primary
        }
        return AppColors.textSecondary
    }
}

// MARK: - Preview Provider

#if DEBUG
struct SecureInput_Previews: PreviewProvider {
    static var previews: some View {
        VStack(spacing: AppSpacing.xl) {
            SecureInput("Password", text: .constant(""))

            SecureInput("Password", text: .constant("secret123"))

            SecureInput(
                "Password",
                text: .constant(""),
                helperText: "Minimum 8 characters"
            )

            SecureInput(
                "Password",
                text: .constant("weak"),
                errorMessage: "Password is too weak"
            )

            SecureInput(
                "Password",
                text: .constant("locked"),
                isDisabled: true
            )
        }
        .padding()
        .background(AppColors.background)
        .previewDisplayName("Secure Input States")
    }
}
#endif