import SwiftUI

/// Simple load state for screen view models.
enum LoadPhase: Equatable {
    case idle
    case loading
    case loaded
    case failed(String)
}

// MARK: - State / severity badges

struct StateBadge: View {
    let text: String
    let color: Color

    var body: some View {
        Text(text)
            .font(.caption2.weight(.semibold))
            .padding(.horizontal, 8)
            .padding(.vertical, 3)
            .background(color.opacity(0.18))
            .foregroundStyle(color)
            .clipShape(Capsule())
    }
}

extension ONULifecycleState {
    var color: Color {
        switch self {
        case .registered:      return .green
        case .unspecified:     return .mint      // also "online" (dev guide Procedure 2)
        case .unprovisioned:   return .blue
        case .deregistered:    return .gray
        case .dyingGasp, .disallowedError:                  return .red
        case .disabled, .disallowedAdmin, .disallowedRegID: return .orange
        case .unknown:         return .secondary
        }
    }
    var label: String { self == .unknown ? "Unknown" : rawValue }
}

extension DeviceState {
    var color: Color {
        switch self {
        case .online: return .green
        case .offline: return .gray
        case .unattached: return .orange
        case .preProvisioned: return .blue
        case .unknown: return .secondary
        }
    }
    var label: String { self == .unknown ? "Unknown" : rawValue }
}

extension AlarmSeverity {
    var color: Color {
        switch self {
        case .emergency, .alert, .critical: return .red
        case .error: return .orange
        case .warning: return .yellow
        case .notice, .info: return .blue
        case .debug: return .gray
        case .unknown: return .secondary
        }
    }
    var label: String { self == .unknown ? "unknown" : rawValue }
}

struct SeverityBadge: View {
    let severity: AlarmSeverity
    var body: some View { StateBadge(text: severity.label, color: severity.color) }
}

// MARK: - Count tile (dashboard)

struct CountTile: View {
    let title: String
    let value: Int
    var systemImage: String? = nil
    var tint: Color = .accentColor

    var body: some View {
        VStack(alignment: .leading, spacing: 6) {
            HStack(spacing: 6) {
                if let systemImage { Image(systemName: systemImage).foregroundStyle(tint) }
                Text(title).font(.caption).foregroundStyle(.secondary)
            }
            Text("\(value)").font(.system(.title, design: .rounded).weight(.semibold))
        }
        .frame(maxWidth: .infinity, alignment: .leading)
        .padding()
        .background(Color(.secondarySystemBackground))
        .clipShape(RoundedRectangle(cornerRadius: 14, style: .continuous))
    }
}

// MARK: - Loading / error

struct LoadingView: View {
    var label: String = "Loading…"
    var body: some View {
        VStack(spacing: 12) {
            ProgressView()
            Text(label).font(.subheadline).foregroundStyle(.secondary)
        }
        .frame(maxWidth: .infinity, maxHeight: .infinity)
    }
}

struct ErrorStateView: View {
    let message: String
    var retry: (() -> Void)? = nil

    var body: some View {
        ContentUnavailableView {
            Label("Something went wrong", systemImage: "exclamationmark.triangle")
        } description: {
            Text(message)
        } actions: {
            if let retry {
                Button("Retry", action: retry).buttonStyle(.borderedProminent)
            }
        }
    }
}