import SwiftUI
import Bedrock

/// Displays a preview of the shared card with option to save to Contacts.
struct ClipCardPreview: View {
    private struct ContactSection {
        let title: String
        let rows: [SharedCardSnapshot.ContactInfoRow]
    }

    let snapshot: SharedCardSnapshot
    /// Called when share sheet is dismissed; use for CloudKit cleanup.
    let onSave: () -> Void

    @State private var showShareSheet = false

    var body: some View {
        ScrollView(showsIndicators: false) {
            VStack(spacing: ClipDesign.Spacing.xLarge) {
                previewCard
                    .frame(maxWidth: ClipDesign.Size.previewMaxWidth)

                VStack(spacing: ClipDesign.Spacing.medium) {
                // Add to Contacts - uses share sheet because App Clips cannot use CNContactStore
                ClipPrimaryButton(
                    title: String(localized: "Add to Contacts"),
                    systemImage: "person.crop.circle.badge.plus",
                    action: { showShareSheet = true }
                )
                .accessibilityLabel(Text("Add \(snapshot.displayName) to contacts"))

                // Get full app prompt
                Button {
                    openAppStore()
                } label: {
                    Text(String(localized: "Get the full app"))
                        .styled(.subheading)
                        .foregroundStyle(Color.Clip.accent)
                }
                }
                .padding(.horizontal, ClipDesign.Spacing.xLarge)
            }
            .padding(.horizontal, ClipDesign.Spacing.large)
        }
        .sheet(isPresented: $showShareSheet) {
            ClipShareSheet(vCardData: snapshot.vCardData) {
                showShareSheet = false
                onSave()
            }
        }
    }

    private var previewCard: some View {
        VStack(spacing: 0) {
            previewHeader

            VStack(alignment: .leading, spacing: ClipDesign.Spacing.medium) {
                Text(snapshot.displayName)
                    .styled(.title2)
                    .foregroundStyle(Color.Clip.text)
                    .multilineTextAlignment(.center)
                    .lineLimit(2)
                    .minimumScaleFactor(0.8)
                    .frame(maxWidth: .infinity, alignment: .center)

                if !snapshot.role.isEmpty || !snapshot.company.isEmpty {
                    VStack(spacing: ClipDesign.Spacing.xSmall) {
                        if !snapshot.role.isEmpty {
                            Text(snapshot.role)
                                .styled(.headingEmphasis)
                                .foregroundStyle(Color.Clip.text)
                                .multilineTextAlignment(.center)
                                .lineLimit(1)
                                .frame(maxWidth: .infinity, alignment: .center)
                        }
                        
                        if !snapshot.company.isEmpty {
                            Text(snapshot.company)
                                .styled(.subheading)
                                .foregroundStyle(Color.Clip.secondaryText)
                                .multilineTextAlignment(.center)
                                .lineLimit(1)
                                .frame(maxWidth: .infinity, alignment: .center)
                        }
                    }
                    .frame(maxWidth: .infinity, alignment: .center)
                }

                Divider()
                    .overlay(Color.Clip.secondaryText.opacity(ClipDesign.Opacity.faint))

                if !contactSections.isEmpty {
                    contactSectionsView

                    Divider()
                        .overlay(Color.Clip.secondaryText.opacity(ClipDesign.Opacity.faint))
                }

                Text(String(localized: "Shared business card"))
                    .styled(.caption)
                    .foregroundStyle(Color.Clip.secondaryText)
                    .frame(maxWidth: .infinity, alignment: .center)
            }
            .padding(.horizontal, ClipDesign.Spacing.xLarge)
            .padding(.bottom, ClipDesign.Spacing.xLarge)
        }
        .frame(minHeight: ClipDesign.Size.previewCardMinHeight)
        .background(Color.Clip.cardBackground)
        .clipShape(.rect(cornerRadius: ClipDesign.CornerRadius.xLarge))
        .shadow(
            color: Color.Clip.text.opacity(ClipDesign.Opacity.faint),
            radius: ClipDesign.Shadow.radius,
            x: 0,
            y: ClipDesign.Shadow.y
        )
        .overlay(
            RoundedRectangle(cornerRadius: ClipDesign.CornerRadius.xLarge)
                .stroke(Color.Clip.secondaryText.opacity(ClipDesign.Opacity.subtle), lineWidth: ClipDesign.Size.cardStrokeWidth)
        )
    }

    private var contactSectionsView: some View {
        VStack(alignment: .leading, spacing: ClipDesign.Spacing.medium) {
            ForEach(contactSections, id: \.title) { section in
                VStack(alignment: .leading, spacing: ClipDesign.Spacing.xSmall) {
                    Text(section.title.uppercased())
                        .styled(.caption)
                        .foregroundStyle(Color.Clip.secondaryText)
                        .frame(maxWidth: .infinity, alignment: .leading)

                    VStack(spacing: 0) {
                        ForEach(Array(section.rows.enumerated()), id: \.element.id) { index, row in
                            contactRow(row)
                                .padding(.horizontal, ClipDesign.Spacing.medium)
                                .padding(.vertical, ClipDesign.Spacing.small)

                            if index < section.rows.count - 1 {
                                Divider()
                                    .overlay(Color.Clip.secondaryText.opacity(ClipDesign.Opacity.faint))
                                    .padding(.leading, ClipDesign.Spacing.medium)
                            }
                        }
                    }
                    .background(Color.Clip.background.opacity(ClipDesign.Opacity.faint))
                    .clipShape(.rect(cornerRadius: ClipDesign.CornerRadius.medium))
                    .overlay(
                        RoundedRectangle(cornerRadius: ClipDesign.CornerRadius.medium)
                            .stroke(Color.Clip.secondaryText.opacity(ClipDesign.Opacity.faint), lineWidth: ClipDesign.Size.cardStrokeWidth)
                    )
                }
            }
        }
        .frame(maxWidth: .infinity, alignment: .leading)
    }

    private func contactRow(_ row: SharedCardSnapshot.ContactInfoRow) -> some View {
        HStack(alignment: .top, spacing: ClipDesign.Spacing.small) {
            Image(systemName: row.systemImage)
                .font(.system(size: ClipDesign.Size.contactRowIconSize, weight: .semibold))
                .foregroundStyle(Color.Clip.secondaryText)
                .frame(width: ClipDesign.Size.contactRowIconSize + ClipDesign.Spacing.small)

            VStack(alignment: .leading, spacing: ClipDesign.Spacing.xSmall) {
                Text(row.value)
                    .styled(.subheading)
                    .foregroundStyle(Color.Clip.text)
                    .lineLimit(row.kind == .note ? nil : 2)
                    .truncationMode(.tail)
                    .frame(maxWidth: .infinity, alignment: .leading)

                Text(row.label)
                    .styled(.caption)
                    .foregroundStyle(Color.Clip.secondaryText)
                    .frame(maxWidth: .infinity, alignment: .leading)
            }
            .frame(maxWidth: .infinity, alignment: .leading)
        }
        .frame(maxWidth: .infinity, alignment: .leading)
    }

    private var contactSections: [ContactSection] {
        let groups = Dictionary(grouping: snapshot.contactInfoRows, by: \.kind)
        let order: [(SharedCardSnapshot.ContactInfoRow.Kind, String)] = [
            (.phone, String(localized: "Phone")),
            (.email, String(localized: "Email")),
            (.address, String(localized: "Address")),
            (.website, String(localized: "Links")),
            (.social, String(localized: "Social Profiles")),
            (.note, String(localized: "Notes"))
        ]

        return order.compactMap { kind, title in
            guard let rows = groups[kind], !rows.isEmpty else { return nil }
            return ContactSection(title: title, rows: rows)
        }
    }

    private var previewHeader: some View {
        ZStack(alignment: .bottom) {
            LinearGradient(
                colors: [
                    Color.Clip.accent.opacity(ClipDesign.Opacity.strong),
                    Color.Clip.accent.opacity(ClipDesign.Opacity.subtle)
                ],
                startPoint: .topLeading,
                endPoint: .bottomTrailing
            )
            .frame(height: ClipDesign.Size.previewBannerHeight)

            avatarView
                .offset(y: ClipDesign.Size.previewAvatarOverlap)
        }
        .padding(.bottom, ClipDesign.Size.previewAvatarOverlap)
    }

    private var avatarView: some View {
        ZStack {
            Circle()
                .fill(Color.Clip.background.opacity(ClipDesign.Opacity.medium))

            if let photoData = snapshot.photoData, let uiImage = UIImage(data: photoData) {
                Image(uiImage: uiImage)
                    .resizable()
                    .scaledToFill()
            } else {
                Image(systemName: "person.fill")
                    .resizable()
                    .scaledToFit()
                    .frame(width: ClipDesign.Size.avatarFallbackSymbolSize, height: ClipDesign.Size.avatarFallbackSymbolSize)
                    .foregroundStyle(Color.Clip.secondaryText)
            }
        }
        .frame(width: ClipDesign.Size.previewAvatarSize, height: ClipDesign.Size.previewAvatarSize)
        .clipShape(.circle)
        .overlay(
            Circle()
                .stroke(Color.Clip.cardBackground, lineWidth: ClipDesign.Size.avatarStrokeWidth)
        )
        .shadow(
            color: Color.Clip.text.opacity(ClipDesign.Opacity.faint),
            radius: ClipDesign.Shadow.radius,
            x: 0,
            y: ClipDesign.Shadow.y
        )
    }

    private func openAppStore() {
        if let url = URL(string: ClipDesign.URL.appStore) {
            UIApplication.shared.open(url)
        }
    }
}

#Preview {
    ZStack {
        Color.Clip.background
            .ignoresSafeArea()

        ClipCardPreview(
            snapshot: SharedCardSnapshot(
                recordName: "test",
                vCardData: """
                BEGIN:VCARD
                VERSION:3.0
                N:Sullivan;Daniel;;;
                FN:Daniel Sullivan
                ORG:WR Construction
                TITLE:Property Developer
                END:VCARD
                """
            )
        ) {
            print("Save tapped")
        }
    }
}