//
//  MockStatusView.swift
//  Tusker
//
//  Created by Shadowfacts on 4/13/24.
//  Copyright © 2024 Shadowfacts. All rights reserved.
//

import SwiftUI
import Pachyderm
import WebURL

struct MockStatusView: View {
    @ObservedObject private var preferences = Preferences.shared
    @ScaledMetric(relativeTo: .body) private var attachmentsLabelHeight = 17
    
    var body: some View {
        HStack(alignment: .top, spacing: 8) {
            VStack(spacing: 4) {
                Image("AboutIcon")
                    .resizable()
                    .clipShape(RoundedRectangle(cornerRadius: preferences.avatarStyle.cornerRadiusFraction * 50))
                    .frame(width: 50, height: 50)
                
                MockMetaIndicatorsView()
                
                Spacer()
            }
            
            VStack(alignment: .leading, spacing: 4) {
                HStack(spacing: 4) {
                    MockDisplayNameLabel()
                    Text(verbatim: "@tusker@example.com")
                        .foregroundStyle(.secondary)
                        .font(.body.weight(.light))
                        .lineLimit(1)
                        .truncationMode(.tail)
                        .layoutPriority(-100)
                    Spacer()
                    Text("1h")
                        .foregroundStyle(.secondary)
                        .font(.body.weight(.light))
                }
                
                MockStatusContentView()
                
                if preferences.showLinkPreviews {
                    MockStatusCardView()
                        .frame(height: StatusContentContainer.cardViewHeight)
                }
                
                MockAttachmentsContainerView()
                    .aspectRatio(preferences.showAttachmentsInTimeline ? 16/9 : nil, contentMode: .fill)
                    .frame(height: preferences.showAttachmentsInTimeline ? nil : attachmentsLabelHeight)
                    .padding(.bottom, preferences.showAttachmentsInTimeline && preferences.hideActionsInTimeline ? 8 : 0)
                
                if !preferences.hideActionsInTimeline {
                    MockStatusActionButtons()
                }
            }
            .layoutPriority(100)
        }
    }
}

private struct MockMetaIndicatorsView: UIViewRepresentable {
    @ObservedObject private var preferences = Preferences.shared
    
    func makeUIView(context: Context) -> StatusMetaIndicatorsView {
        let view = StatusMetaIndicatorsView()
        view.primaryAxis = .vertical
        view.secondaryAxisAlignment = .trailing
        return view
    }
    
    func updateUIView(_ uiView: StatusMetaIndicatorsView, context: Context) {
        var indicators: StatusMetaIndicatorsView.Indicator = []
        if preferences.showIsStatusReplyIcon {
            indicators.insert(.reply)
        }
        if preferences.alwaysShowStatusVisibilityIcon {
            indicators.insert(.visibility)
        }
        uiView.setIndicators(indicators, visibility: .public)
    }
}

private struct MockDisplayNameLabel: View {
    @ObservedObject private var preferences = Preferences.shared
    @ScaledMetric(relativeTo: .body) private var emojiSize = 17
    @State var textWithImage = Text("Tusker")
    
    var body: some View {
        displayName
            .font(.body.weight(.semibold))
            // don't let the height change depending on whether emojis are present or not
            .frame(height: emojiSize)
            .task(id: emojiSize) {
                let size = CGSize(width: emojiSize, height: emojiSize)
                let renderer = UIGraphicsImageRenderer(size: size)
                let image = renderer.image { ctx in
                    let bounds = CGRect(origin: .zero, size: size)
                    UIBezierPath(roundedRect: bounds, cornerRadius: 2).addClip()
                    UIImage(named: "AboutIcon")!.draw(in: bounds)
                }
                textWithImage = Text("Tusker \(Image(uiImage: image))")
            }
    }
    
    private var displayName: Text {
        if preferences.hideCustomEmojiInUsernames {
            Text("Tusker")
        } else {
            textWithImage
        }
    }
}

private struct MockStatusContentView: View {
    @ObservedObject private var preferences = Preferences.shared
    
    var body: some View {
        Text("This is an example post so you can check out how things look.\n\nThanks for using \(link)!")
            .lineLimit(nil)
    }
    
    private var link: Text {
        Text("Tusker")
            .foregroundColor(.accentColor)
            .underline(preferences.underlineTextLinks)
    }
}

private struct MockStatusCardView: UIViewRepresentable {
    func makeUIView(context: Context) -> StatusCardView {
        let view = StatusCardView()
        view.isUserInteractionEnabled = false
        let card = Card(
            url: WebURL("https://vaccor.space/tusker")!,
            title: "Tusker",
            description: "Tusker is an iOS app for Mastodon",
            image: WebURL("https://vaccor.space/tusker/img/icon.png")!,
            kind: .link
        )
        view.updateUI(card: card, sensitive: false)
        return view
    }
    
    func updateUIView(_ uiView: StatusCardView, context: Context) {
    }
}

private actor MockAttachmentsGenerator {
    static let shared = MockAttachmentsGenerator()
    
    private var attachmentURLs: [URL]?
    
    func getAttachmentURLs(displayScale: CGFloat) -> [URL] {
        if let attachmentURLs,
           attachmentURLs.allSatisfy({ FileManager.default.fileExists(atPath: $0.path) }) {
            return attachmentURLs
        }
        
        let size = CGSize(width: 100, height: 100)
        let bounds = CGRect(origin: .zero, size: size)
        let format = UIGraphicsImageRendererFormat()
        format.scale = displayScale
        let renderer = UIGraphicsImageRenderer(size: size, format: format)
        
        let firstImage = renderer.image { ctx in
            UIColor(red: 0x56 / 255, green: 0x03 / 255, blue: 0xad / 255, alpha: 1).setFill()
            ctx.fill(bounds)
            ctx.cgContext.concatenate(CGAffineTransform(1, 0, -0.5, 1, 0, 0))
            for minX in stride(from: 0, through: 100, by: 30) {
                UIColor(red: 0x83 / 255, green: 0x67 / 255, blue: 0xc7 / 255, alpha: 1).setFill()
                ctx.fill(CGRect(x: minX + 20, y: 0, width: 15, height: 100))
            }
        }
        let secondImage = renderer.image { ctx in
            UIColor(red: 0x00 / 255, green: 0x43 / 255, blue: 0x85 / 255, alpha: 1).setFill()
            ctx.fill(bounds)
            UIColor(red: 0x05 / 255, green: 0xb2 / 255, blue: 0xdc / 255, alpha: 1).setFill()
            for y in 0..<2 {
                for x in 0..<4 {
                    let rect = CGRect(x: x * 45 - 5, y: y * 50 + 15, width: 20, height: 20)
                    ctx.cgContext.fillEllipse(in: rect)
                }
            }
            UIColor(red: 0x08 / 255, green: 0x7c / 255, blue: 0xa7 / 255, alpha: 1).setFill()
            for y in 0..<3 {
                for x in 0..<2 {
                    let rect = CGRect(x: CGFloat(x) * 45 + 22.5, y: CGFloat(y) * 50 - 5, width: 10, height: 10)
                    ctx.cgContext.fillEllipse(in: rect)
                }
            }
        }

        let tempDirectory = FileManager.default.temporaryDirectory
        let firstURL = tempDirectory.appendingPathComponent("\(UUID().description)", conformingTo: .png)
        let secondURL = tempDirectory.appendingPathComponent("\(UUID().description)", conformingTo: .png)
        
        do {
            try firstImage.pngData()!.write(to: firstURL)
            try secondImage.pngData()!.write(to: secondURL)
            attachmentURLs = [firstURL, secondURL]
            return [firstURL, secondURL]
        } catch {
            return []
        }
    }
}

private struct MockAttachmentsContainerView: View {
    @State private var attachments: [Attachment] = []
    @Environment(\.displayScale) private var displayScale
    
    var body: some View {
        MockAttachmentsContainerRepresentable(attachments: attachments)
            .task {
                let attachmentURLs = await MockAttachmentsGenerator.shared.getAttachmentURLs(displayScale: displayScale)
                self.attachments = [
                    .init(id: "1", kind: .image, url: attachmentURLs[0], description: "test"),
                    .init(id: "2", kind: .image, url: attachmentURLs[1], description: nil),
                ]
            }
    }
}

private struct MockAttachmentsContainerRepresentable: UIViewRepresentable {
    let attachments: [Attachment]
    @ObservedObject private var preferences = Preferences.shared

    func makeUIView(context: Context) -> AttachmentsContainerView {
        let view = AttachmentsContainerView()
        view.isUserInteractionEnabled = false
        return view
    }
    
    func updateUIView(_ uiView: AttachmentsContainerView, context: Context) {
        uiView.updateUI(attachments: attachments, labelOnly: !preferences.showAttachmentsInTimeline)
        uiView.contentHidden = preferences.attachmentBlurMode == .always
        for attachmentView in uiView.attachmentViews.allObjects {
            attachmentView.updateBadges()
        }
    }
}

private struct MockStatusActionButtons: View {
    var body: some View {
        HStack(spacing: 0) {
            Image(systemName: "arrowshape.turn.up.left.fill")
                .foregroundStyle(.tint)
            Spacer()
            Image(systemName: "star.fill")
                .foregroundStyle(.tint)
            Spacer()
            Image(systemName: "repeat")
                .foregroundStyle(.yellow)
            Spacer()
            Image(systemName: "ellipsis")
                .foregroundStyle(.tint)
            Spacer()
        }
    }
}

#Preview {
    MockStatusView()
        .frame(height: 300)
}