import SwiftUI

enum MessageAction {
	case resend(Message)
	case delete(Message)
}

struct MessageView: View {
	@Dependency private var client: RocketChatClientProtocol
	
	@ObservedObject private var viewModel: MessageViewModel
	
	@State private var message: Message?
	
	private let action: (MessageAction) -> Void
	
	init(viewModel: MessageViewModel, action: @escaping (MessageAction) -> Void) {
		self.action = action
		self.viewModel = viewModel
	}
	
	@ViewBuilder
	private var unreadSeparator: some View {
		HStack(alignment: .center) {
			Text("Unread messages")
				.lineLimit(1)
				.font(.footnote)
				.foregroundStyle(.red)
				.layoutPriority(1)
			VStack(alignment: .center) {
				Divider()
					.overlay(.red)
			}
		}
	}
	
	@ViewBuilder
	private var dateSeparator: some View {
		HStack(alignment: .center) {
			VStack(alignment: .center) {
				Divider()
					.overlay(.secondary)
			}
			Text(viewModel.date ?? "")
				.lineLimit(1)
				.font(.footnote)
				.foregroundStyle(.secondary)
				.layoutPriority(1)
			VStack(alignment: .center) {
				Divider()
					.overlay(.secondary)
			}
		}
	}
	
	var body: some View {
		HStack {
			VStack(alignment: .leading, spacing: 0) {
				if viewModel.hasDateSeparator {
					dateSeparator
				} else if viewModel.hasUnreadSeparator {
					unreadSeparator
				}
				if viewModel.isHeader {
					HStack(alignment: .center) {
						Text(viewModel.sender ?? "")
							.lineLimit(1)
							.font(.caption.bold())
							.foregroundStyle(Color.default)
						Text(viewModel.time ?? "")
							.lineLimit(1)
							.font(.footnote)
							.foregroundStyle(.secondary)
						if viewModel.message.editedAt != nil {
							Image(systemName: "pencil")
								.font(.caption)
								.foregroundStyle(.secondary)
						}
					}
					.padding(.bottom, 2)
					.padding(.top, 6)
				}
				if let text = viewModel.info {
					(Text("\(viewModel.sender ?? "") ").font(.caption.bold().italic()) + Text(text).font(.caption.italic()))
						.foregroundStyle(Color.default)
				} else if let text = viewModel.message.msg {
					HStack(alignment: .top) {
						Text(text)
							.font(.caption)
							.foregroundStyle(viewModel.message.foregroundColor)
						
						if viewModel.message.status == "error" {
							Button(
								action: {
									message = viewModel.message
								},
								label: {
									Image(systemName: "exclamationmark.circle")
										.font(.caption)
										.foregroundStyle(.red)
								}
							)
							.buttonStyle(PlainButtonStyle())
						}
						
						if viewModel.message.editedAt != nil && !viewModel.isHeader {
							Image(systemName: "pencil")
								.font(.caption)
								.foregroundStyle(.secondary)
						}
					}
				}
				if let attachments = viewModel.message.attachments?.allObjects as? Array<Attachment> {
					ForEach(attachments) { attachment in
						AttachmentView(attachment: attachment)
					}
				}
			}
			Spacer()
		}
		.padding(.bottom, 2)
		.sheet(item: $message) { message in
			MessageActionView(
				message: message,
				action: action
			)
		}
	}
}

private extension Message {
	var foregroundColor: Color {
		if status == "temp" || status == "error" {
			return Color.secondaryInfo
		}
		
		return Color.default
	}
}