//
//  IconGeneratorView.swift
//  Blackjack
//
//  Development tool to generate and export app icon images.
//  Run this view, tap the button, then find the icons in the Files app.
//

import SwiftUI
import CasinoKit

/// A development view that generates and saves app icon images.
/// After running, find the icons in Files app → On My iPhone → Blackjack
struct IconGeneratorView: View {
    @State private var status: String = "Tap the button to generate icons"
    @State private var isGenerating = false
    @State private var generatedIcons: [GeneratedIcon] = []
    
    // Development view: hardcoded sizes acceptable
    private let previewSize: CGFloat = 200
    private let iconCornerRadiusRatio: CGFloat = 0.22
    
    var body: some View {
        NavigationStack {
            ScrollView {
                VStack(spacing: Design.Spacing.xxLarge) {
                    // Preview
                    AppIconView(config: .blackjack, size: previewSize)
                        .clipShape(.rect(cornerRadius: previewSize * iconCornerRadiusRatio))
                        .shadow(radius: 10)
                    
                    Text("App Icon Preview")
                        .font(.headline)
                    
                    // Generate button
                    Button {
                        Task {
                            await generateIcons()
                        }
                    } label: {
                        HStack {
                            if isGenerating {
                                ProgressView()
                                    .tint(.white)
                            }
                            Text(isGenerating ? "Generating..." : "Generate & Save Icons")
                        }
                        .font(.headline)
                        .foregroundStyle(.white)
                        .frame(maxWidth: .infinity)
                        .padding()
                        .background(isGenerating ? Color.gray : Color.blue)
                        .clipShape(.rect(cornerRadius: 12))
                    }
                    .disabled(isGenerating)
                    .padding(.horizontal)
                    
                    // Status
                    Text(status)
                        .font(.callout)
                        .foregroundStyle(.secondary)
                        .multilineTextAlignment(.center)
                        .padding(.horizontal)
                    
                    // Generated icons
                    if !generatedIcons.isEmpty {
                        VStack(alignment: .leading, spacing: 12) {
                            Text("Generated Icons:")
                                .font(.headline)
                            
                            ForEach(generatedIcons) { icon in
                                HStack {
                                    Image(systemName: "checkmark.circle.fill")
                                        .foregroundStyle(.green)
                                    Text(icon.filename)
                                        .font(.caption.monospaced())
                                    Spacer()
                                    Text("\(Int(icon.size))px")
                                        .font(.caption)
                                        .foregroundStyle(.secondary)
                                }
                            }
                        }
                        .padding()
                        .background(Color.green.opacity(Design.Opacity.subtle))
                        .clipShape(.rect(cornerRadius: Design.CornerRadius.medium))
                        .padding(.horizontal)
                    }
                    
                    // Instructions
                    instructionsSection
                }
                .padding(.vertical)
            }
            .navigationTitle("Icon Generator")
        }
    }
    
    private var instructionsSection: some View {
        VStack(alignment: .leading, spacing: 12) {
            Text("After generating:")
                .font(.headline)
            
            VStack(alignment: .leading, spacing: Design.Spacing.small) {
                instructionRow(number: 1, text: "Open Files app on your device/simulator")
                instructionRow(number: 2, text: "Navigate to: On My iPhone → Blackjack")
                instructionRow(number: 3, text: "Find the AppIcon-1024.png file")
                instructionRow(number: 4, text: "AirDrop or share to your Mac")
                instructionRow(number: 5, text: "Drag into Xcode's Assets.xcassets/AppIcon")
            }
            
            Divider()
            
            Text("Alternative: Use an online tool")
                .font(.subheadline.bold())
            Text("Upload the 1024px icon to appicon.co or makeappicon.com to generate all sizes automatically.")
                .font(.caption)
                .foregroundStyle(.secondary)
        }
        .padding()
        .background(Color.gray.opacity(Design.Opacity.subtle))
        .clipShape(.rect(cornerRadius: Design.CornerRadius.medium))
        .padding(.horizontal)
    }
    
    private func instructionRow(number: Int, text: String) -> some View {
        HStack(alignment: .top, spacing: 8) {
            Text("\(number).")
                .font(.callout.bold())
                .foregroundStyle(.blue)
            Text(text)
                .font(.callout)
        }
    }
    
    @MainActor
    private func generateIcons() async {
        isGenerating = true
        generatedIcons = []
        status = "Generating icons..."
        
        let sizes: [(CGFloat, String)] = [
            (1024, "AppIcon-1024"),
            (180, "AppIcon-180"),
            (120, "AppIcon-120"),
            (87, "AppIcon-87"),
            (80, "AppIcon-80"),
            (60, "AppIcon-60"),
            (40, "AppIcon-40")
        ]
        
        let documentsPath = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
        
        for (size, name) in sizes {
            // Render the icon
            let view = AppIconView(config: .blackjack, size: size)
            let renderer = ImageRenderer(content: view)
            renderer.scale = 1.0
            
            if let uiImage = renderer.uiImage,
               let data = uiImage.pngData() {
                let filename = "\(name).png"
                let fileURL = documentsPath.appending(path: filename)
                
                do {
                    try data.write(to: fileURL)
                    generatedIcons.append(GeneratedIcon(filename: filename, size: size))
                } catch {
                    status = "Error saving \(filename): \(error.localizedDescription)"
                }
            }
            
            // Small delay for UI feedback
            try? await Task.sleep(for: .milliseconds(100))
        }
        
        if generatedIcons.count == sizes.count {
            status = "✅ All icons saved to Documents folder!\nOpen Files app to find them."
        } else {
            status = "⚠️ Some icons failed to generate"
        }
        
        isGenerating = false
    }
}

struct GeneratedIcon: Identifiable {
    let id = UUID()
    let filename: String
    let size: CGFloat
}

#Preview {
    IconGeneratorView()
}