import SwiftUI

struct DogsListView: View {
    @State private var dogs: [Dog] = []
    @State private var isLoading = false
    @State private var errorMessage: String?

    var body: some View {
        NavigationStack {
            content
                .navigationTitle("Hunde")
                .task { await load() }
        }
    }

    @ViewBuilder
    private var content: some View {
        if isLoading && dogs.isEmpty {
            ProgressView()
        } else if let error = errorMessage, dogs.isEmpty {
            ContentUnavailableView(
                "Konnte Hunde nicht laden",
                systemImage: "wifi.slash",
                description: Text(error)
            )
        } else if dogs.isEmpty {
            ContentUnavailableView(
                "Keine Hunde",
                systemImage: "pawprint",
                description: Text("Lege deinen ersten Hund in der PWA an.")
            )
        } else {
            List(dogs) { dog in
                DogRow(dog: dog)
            }
            .refreshable { await load() }
        }
    }

    private func load() async {
        isLoading = true
        errorMessage = nil
        defer { isLoading = false }
        do {
            dogs = try await APIClient.shared.get("/api/dogs")
        } catch {
            errorMessage = error.localizedDescription
        }
    }
}

struct DogRow: View {
    let dog: Dog

    var body: some View {
        HStack(spacing: 12) {
            avatar
                .frame(width: 56, height: 56)
                .background(.background.secondary)
                .clipShape(Circle())

            VStack(alignment: .leading, spacing: 2) {
                Text(dog.name).font(.headline)
                if let rasse = dog.rasse, !rasse.isEmpty {
                    Text(rasse)
                        .font(.subheadline)
                        .foregroundStyle(.secondary)
                }
            }
        }
        .padding(.vertical, 4)
    }

    @ViewBuilder
    private var avatar: some View {
        if let path = dog.fotoUrl, let url = URL(string: "https://banyaro.app\(path)") {
            AsyncImage(url: url) { phase in
                switch phase {
                case .success(let img):
                    img.resizable().scaledToFill()
                default:
                    placeholder
                }
            }
        } else {
            placeholder
        }
    }

    private var placeholder: some View {
        Image(systemName: "pawprint.fill")
            .font(.title2)
            .foregroundStyle(.secondary)
            .frame(maxWidth: .infinity, maxHeight: .infinity)
    }
}