import SwiftUI

struct SplashScreenView: View {
    @Bindable var viewModel: SplashViewModel
    @Environment(AppearanceManager.self) private var appearanceManager
    @State private var contentScale: CGFloat = 0.9
    @State private var contentOpacity: Double = 0
    @State private var detailsOpacity: Double = 0
    @State private var glowPulse = false

    var body: some View {
        let isDark = appearanceManager.isDarkMode

        ZStack {
            background(isDark: isDark)
            glowOrb(isDark: isDark)

            VStack(spacing: 28) {
                brandMark

                VStack(spacing: 24) {
                    VStack(spacing: 10) {
                        title
                        Text("AI Assistant for Reddit")
                            .font(.system(size: 14, weight: .medium))
                            .foregroundStyle(AppTheme.textSecondary)
                    }

                    loadingBar
                }
                .opacity(detailsOpacity)
            }
            .frame(maxWidth: .infinity, maxHeight: .infinity)
            .scaleEffect(contentScale)
            .opacity(contentOpacity)
        }
        .frame(maxWidth: .infinity, maxHeight: .infinity)
        .ignoresSafeArea()
        .onAppear {
            withAnimation(.spring(response: 0.62, dampingFraction: 0.78)) {
                contentScale = 1
                contentOpacity = 1
            }
            withAnimation(.easeOut(duration: 0.55).delay(0.12)) {
                detailsOpacity = 1
            }
            withAnimation(.easeInOut(duration: 2.4).repeatForever(autoreverses: true)) {
                glowPulse = true
            }
        }
    }

    private func background(isDark: Bool) -> some View {
        Group {
            if isDark {
                AppTheme.background
            } else {
                LinearGradient(
                    colors: [
                        Color(hex: 0xF3F0FF),
                        AppTheme.background
                    ],
                    startPoint: .top,
                    endPoint: .bottom
                )
            }
        }
        .ignoresSafeArea()
    }

    private func glowOrb(isDark: Bool) -> some View {
        Circle()
            .fill(
                RadialGradient(
                    colors: [
                        AppTheme.accentPurple.opacity(isDark ? 0.22 : 0.14),
                        Color.clear
                    ],
                    center: .center,
                    startRadius: 0,
                    endRadius: 280
                )
            )
            .frame(width: 560, height: 560)
            .scaleEffect(glowPulse ? 1.06 : 0.94)
            .offset(x: 180, y: -220)
            .allowsHitTesting(false)
    }

    private var brandMark: some View {
        Image("AppLogo")
            .resizable()
            .interpolation(.high)
            .scaledToFit()
            .frame(width: 80, height: 80)
            .shadow(color: Color(hex: 0xFF4500).opacity(0.35), radius: 28, y: 10)
    }

    private var loadingBar: some View {
        VStack(spacing: 12) {
            GeometryReader { geometry in
                ZStack(alignment: .leading) {
                    Capsule()
                        .fill(AppTheme.border)

                    Capsule()
                        .fill(
                            LinearGradient(
                                colors: [AppTheme.accentPurple, AppTheme.accentPurpleLight],
                                startPoint: .leading,
                                endPoint: .trailing
                            )
                        )
                        .frame(width: max(geometry.size.width * viewModel.loadingProgress, geometry.size.height))
                }
            }
            .frame(width: 300, height: 7)

            Text("Loading…")
                .font(.system(size: 12, weight: .medium))
                .foregroundStyle(AppTheme.textTertiary)
        }
        .frame(maxWidth: .infinity)
    }

    private var title: some View {
        Text(AppLinks.appName)
            .font(.system(size: 34, weight: .bold))
            .tracking(-0.6)
            .foregroundStyle(AppTheme.textPrimary)
    }
}