import SwiftUI

struct PreflightView: View {
    let report:    PreflightReport
    let action:    String
    let onProceed: () -> Void
    let onCancel:  () -> Void

    var body: some View {
        NavigationStack {
            VStack(spacing: 0) {
                summaryHeader.padding(.horizontal, 20).padding(.vertical, 16)
                    .background(headerBg)
                Divider()
                List(report.checks) { check in
                    HStack(spacing: 10) {
                        Image(systemName: check.icon).foregroundStyle(check.color).font(.system(size: 16)).frame(width: 20)
                        VStack(alignment: .leading, spacing: 2) {
                            Text(check.name).font(.subheadline)
                            Text(check.detail).font(.caption).foregroundStyle(.secondary).lineLimit(2)
                        }
                    }
                    .padding(.vertical, 6)
                }
                .listStyle(.plain)
                Divider()
                HStack(spacing: 12) {
                    Button("Cancel", action: onCancel).buttonStyle(.bordered).frame(maxWidth: .infinity)
                    if report.canProceed {
                        Button(action: onProceed) {
                            Label(action == "buildAndRun" ? "Build & Run" : "Build",
                                  systemImage: action == "buildAndRun" ? "play.fill" : "hammer.fill")
                                .frame(maxWidth: .infinity)
                        }
                        .buttonStyle(.borderedProminent)
                        .tint(report.hasWarnings ? .orange : .green)
                    } else {
                        Button("Fix Issues", action: onCancel)
                            .buttonStyle(.borderedProminent).tint(.red).frame(maxWidth: .infinity)
                    }
                }
                .padding(.horizontal, 20).padding(.vertical, 14)
                .background(Color(.secondarySystemBackground))
            }
            .navigationTitle("Pre-Build Checks")
            .navigationBarTitleDisplayMode(.inline)
            .toolbar { ToolbarItem(placement: .cancellationAction) { Button("Cancel", action: onCancel) } }
        }
        .presentationDetents([.medium, .large])
        .presentationDragIndicator(.visible)
    }

    private var summaryHeader: some View {
        HStack(spacing: 14) {
            Image(systemName: summaryIcon).font(.system(size: 36, weight: .medium)).foregroundStyle(summaryColor)
            VStack(alignment: .leading, spacing: 3) {
                Text(summaryTitle).font(.headline)
                Text(summarySubtitle).font(.subheadline).foregroundStyle(.secondary)
            }
            Spacer()
        }
    }

    private var summaryIcon:  String { !report.canProceed ? "xmark.circle.fill" : report.hasWarnings ? "exclamationmark.triangle.fill" : "checkmark.circle.fill" }
    private var summaryColor: Color  { !report.canProceed ? .red : report.hasWarnings ? .orange : .green }
    private var summaryTitle: String { !report.canProceed ? "Build Blocked" : report.hasWarnings ? "Ready with Warnings" : "All Checks Passed" }
    private var headerBg:     Color  { !report.canProceed ? Color.red.opacity(0.08) : report.hasWarnings ? Color.orange.opacity(0.08) : Color.green.opacity(0.08) }

    private var summarySubtitle: String {
        let f = report.checks.filter { if case .fail    = $0.status { return true }; return false }.count
        let w = report.checks.filter { if case .warning = $0.status { return true }; return false }.count
        let p = report.checks.filter { if case .pass    = $0.status { return true }; return false }.count
        var parts: [String] = []
        if f > 0 { parts.append("\(f) failure\(f == 1 ? "" : "s")") }
        if w > 0 { parts.append("\(w) warning\(w == 1 ? "" : "s")") }
        if p > 0 { parts.append("\(p) passed") }
        return parts.joined(separator: " · ")
    }
}