//
//  AppearanceStore.swift
//  Zyquo Router
//
//  Author: Simon-Pierre Boucher
//  Mail: contact@spboucher.ai
//
//  User appearance preferences: theme mode, accent choice, font size.
//  Persisted to appearance.json via PersistenceService. Family design with
//  the Router's accent set: cyan (default) + graphite, sky, emerald, violet,
//  copper.
//

import SwiftUI

/// Accent color choices in Settings → Appearance.
enum AccentChoice: String, Codable, CaseIterable, Identifiable {
    case cyan
    case graphite
    case sky
    case emerald
    case violet
    case copper

    var id: String { rawValue }

    var displayName: String {
        switch self {
        case .cyan: return "Signal Cyan"
        case .graphite: return "Graphite"
        case .sky: return "Sky"
        case .emerald: return "Emerald"
        case .violet: return "Violet"
        case .copper: return "Copper"
        }
    }

    /// (light, dark) accent hex pair.
    var accentHex: (UInt32, UInt32) {
        switch self {
        case .cyan: return (0x0891B2, 0x22B8D4)
        case .graphite: return (0x374151, 0x9AA4B2)
        case .sky: return (0x2E7CD6, 0x5A9BE3)
        case .emerald: return (0x1E9E6A, 0x3CBA87)
        case .violet: return (0x7451D8, 0x9273E4)
        case .copper: return (0xB2622B, 0xC97F4B)
        }
    }

    /// (light, dark) subtle-tint hex pair (selected rows, active tints).
    var subtleHex: (UInt32, UInt32) {
        switch self {
        case .cyan: return (0xE5F5F9, 0x143A44)
        case .graphite: return (0xEEF1F4, 0x2A2F36)
        case .sky: return (0xE8F1FC, 0x1B3350)
        case .emerald: return (0xE6F6EF, 0x173B2C)
        case .violet: return (0xF0EBFB, 0x2C2347)
        case .copper: return (0xF9EFE6, 0x3D2C1D)
        }
    }
}

enum ThemeMode: String, Codable, CaseIterable, Identifiable {
    case system, light, dark
    var id: String { rawValue }

    var displayName: String {
        switch self {
        case .system: return "System"
        case .light: return "Light"
        case .dark: return "Dark"
        }
    }

    var colorScheme: ColorScheme? {
        switch self {
        case .system: return nil
        case .light: return .light
        case .dark: return .dark
        }
    }
}

/// Observable appearance preferences, persisted with the app settings.
@MainActor
final class AppearanceStore: ObservableObject {
    struct Stored: Codable {
        var themeMode: ThemeMode = .system
        var accent: AccentChoice = .cyan
        var fontSize: Double = 13
    }

    static let fileName = "appearance.json"

    @Published var themeMode: ThemeMode { didSet { save() } }
    @Published var accent: AccentChoice { didSet { save() } }
    /// Base body font size, clamped to 12–16pt.
    @Published var fontSize: Double {
        didSet {
            let clamped = min(16, max(12, fontSize))
            if clamped != fontSize { fontSize = clamped }
            save()
        }
    }

    private let persistence: PersistenceService

    init(persistence: PersistenceService = .shared) {
        self.persistence = persistence
        let stored = persistence.load(Stored.self, from: Self.fileName) ?? Stored()
        themeMode = stored.themeMode
        accent = stored.accent
        fontSize = stored.fontSize
    }

    /// Current accent color resolved for the active appearance.
    var accentColor: Color {
        let (light, dark) = accent.accentHex
        return ZyquoColor.dynamic(light: light, dark: dark)
    }

    /// Current subtle accent tint resolved for the active appearance.
    var accentSubtleColor: Color {
        let (light, dark) = accent.subtleHex
        return ZyquoColor.dynamic(light: light, dark: dark)
    }

    private func save() {
        persistence.save(
            Stored(themeMode: themeMode, accent: accent, fontSize: fontSize),
            to: Self.fileName
        )
    }
}