import AppKit
import Foundation
import SwiftUI
import Testing

@testable import Photochk

/// 画面が実際に描けることを確かめる。
///
/// 描いた PNG は一時フォルダに残すので、目視で確認したいときはテスト出力に出るパスを開く。
@Suite("画面の描画")
@MainActor
struct SnapshotTests {
    /// 実物に近い見た目にするため、寸法・容量・撮影日が散らばったグループを作る。
    private func makeFixtureModel() async throws -> (ScanViewModel, URL) {
        let directory = try TestImages.makeTemporaryDirectory()
        let pattern = TestImages.pattern(seed: 42)

        let base = directory.appendingPathComponent("IMG_0001.jpg")
        try TestImages.writeJPEG(pattern, to: base, quality: 0.95)
        try FileManager.default.copyItem(
            at: base, to: directory.appendingPathComponent("IMG_0001のコピー.jpg")
        )
        try TestImages.writeJPEG(
            TestImages.scaled(pattern, factor: 0.5),
            to: directory.appendingPathComponent("IMG_0001_small.jpg"),
            quality: 0.9
        )
        try TestImages.writeJPEG(
            pattern, to: directory.appendingPathComponent("IMG_0001_line.jpg"), quality: 0.3
        )
        let other = TestImages.pattern(seed: 9_999)
        try TestImages.writeJPEG(other, to: directory.appendingPathComponent("IMG_9000.jpg"), quality: 0.95)
        try FileManager.default.copyItem(
            at: directory.appendingPathComponent("IMG_9000.jpg"),
            to: directory.appendingPathComponent("IMG_9000_backup.jpg")
        )

        let groups = try await SimilarityGrouper.run(
            root: directory,
            settings: ScanSettings(includesSubfolders: true, sensitivity: .standard),
            cache: FingerprintCache(fileURL: nil),
            progress: { _ in }
        )

        let model = ScanViewModel()
        model.setGroupsForTesting(groups)
        // サムネイルを先に読み込んでおく。描画時はキャッシュから同期的に出る。
        for group in groups {
            for member in group.members {
                _ = await ThumbnailLoader.shared.thumbnail(for: member.id, size: 168)
                _ = await ThumbnailLoader.shared.thumbnail(for: member.id, size: 52)
            }
        }
        return (model, directory)
    }

    private func render(
        _ view: some View, width: CGFloat, height: CGFloat, name: String
    ) throws -> URL {
        let renderer = ImageRenderer(
            content: view
                .frame(width: width, height: height)
                .background(Color(nsColor: .windowBackgroundColor))
        )
        renderer.scale = 2

        let image = try #require(renderer.nsImage, "\(name) を描画できなかった")
        let tiff = try #require(image.tiffRepresentation)
        let bitmap = try #require(NSBitmapImageRep(data: tiff))
        let png = try #require(bitmap.representation(using: .png, properties: [:]))

        let directory = URL(fileURLWithPath: NSTemporaryDirectory())
            .appendingPathComponent("photochk-snapshots", isDirectory: true)
        try FileManager.default.createDirectory(at: directory, withIntermediateDirectories: true)
        let url = directory.appendingPathComponent("\(name).png")
        try png.write(to: url)
        return url
    }

    @Test("写真タイルが状態ごとに描画できる")
    func rendersPhotoTiles() async throws {
        let (model, directory) = try await makeFixtureModel()
        defer { try? FileManager.default.removeItem(at: directory) }

        let group = try #require(model.groups.first)
        try #require(group.members.count >= 4, "タイルを並べるだけの枚数が必要")

        // 代表 / 通常 / 選択済み / 最後の1枚（選択不可）を横に並べる
        let tiles = HStack(alignment: .top, spacing: 18) {
            PhotoTileView(
                member: group.members[0], isRepresentative: true,
                isMarked: false, canMark: true, onToggle: {}
            )
            PhotoTileView(
                member: group.members[1], isRepresentative: false,
                isMarked: false, canMark: true, onToggle: {}
            )
            PhotoTileView(
                member: group.members[2], isRepresentative: false,
                isMarked: true, canMark: true, onToggle: {}
            )
            PhotoTileView(
                member: group.members[3], isRepresentative: false,
                isMarked: false, canMark: false, onToggle: {}
            )
        }
        .padding(20)

        let url = try render(tiles, width: 800, height: 300, name: "photo-tiles")
        print("[snapshot] \(url.path)")
    }

    @Test("グループ一覧の行が描画できる")
    func rendersGroupRows() async throws {
        let (model, directory) = try await makeFixtureModel()
        defer { try? FileManager.default.removeItem(at: directory) }

        model.applyKeepRule(.highestResolution)

        let rows = VStack(alignment: .leading, spacing: 8) {
            ForEach(model.groups) { group in
                GroupRow(
                    group: group,
                    markedCount: group.members.filter {
                        model.markedForDeletion.contains($0.id)
                    }.count
                )
                Divider()
            }
        }
        .padding(12)

        let url = try render(rows, width: 300, height: 220, name: "group-rows")
        print("[snapshot] \(url.path)")
    }

    @Test("スキャン中の表示が描画できる")
    func rendersProgress() throws {
        let url = try render(
            ScanProgressView(
                progress: ScanProgress(phase: .fingerprinting, completed: 128, total: 940),
                onCancel: {}
            ),
            width: 420, height: 220, name: "progress"
        )
        print("[snapshot] \(url.path)")
    }
}