import Foundation

/// 旅拍相册 OTG 照片落盘实现：写入 scoped 本地目录并通知传输管道。
@MainActor
final class TravelAlbumOTGPhotoSink: OTGPhotoSink {
    private let albumId: Int
    private let accountKey: String
    private let pipeline: WiredCameraTransferPipeline
    private let existingObjectIDsProvider: () async -> Set<String>
    private let autoUploadProvider: () -> Bool

    /// 初始化旅拍相册 OTG 落盘实现。
    init(
        albumId: Int,
        accountKey: String,
        pipeline: WiredCameraTransferPipeline,
        existingObjectIDsProvider: @escaping () async -> Set<String>,
        autoUploadProvider: @escaping () -> Bool
    ) {
        self.albumId = albumId
        self.accountKey = accountKey
        self.pipeline = pipeline
        self.existingObjectIDsProvider = existingObjectIDsProvider
        self.autoUploadProvider = autoUploadProvider
    }

    /// 保存边拍边传图像数据。
    func saveLiveShot(
        data: Data,
        filename: String,
        capturedAt: Date,
        cameraObjectID: String
    ) async throws -> SavedOTGPhoto {
        let fileURL = try OTGPhotoFileWriter.writeImage(
            data,
            filename: filename,
            accountKey: accountKey,
            albumID: albumId
        )
        return ingestSavedFile(
            fileURL: fileURL,
            filename: filename,
            capturedAt: capturedAt,
            cameraObjectID: cameraObjectID
        )
    }

    /// 保存历史导入已下载文件。
    func saveDownloadedFile(
        at url: URL,
        filename: String,
        capturedAt: Date,
        cameraObjectID: String
    ) async throws -> SavedOTGPhoto {
        let fileURL = try OTGPhotoFileWriter.moveDownloadedFile(
            from: url,
            filename: filename,
            accountKey: accountKey,
            albumID: albumId
        )
        return ingestSavedFile(
            fileURL: fileURL,
            filename: filename,
            capturedAt: capturedAt,
            cameraObjectID: cameraObjectID
        )
    }

    /// 返回当前相册已导入的相机对象 ID。
    func existingCameraObjectIDs() async -> Set<String> {
        await existingObjectIDsProvider()
    }

    private func ingestSavedFile(
        fileURL: URL,
        filename: String,
        capturedAt: Date,
        cameraObjectID: String
    ) -> SavedOTGPhoto {
        let relativePath = OTGPhotoFileWriter.relativePath(for: fileURL)
        let autoUpload = autoUploadProvider()
        pipeline.ingestDownloadedAsset(
            assetID: cameraObjectID,
            filename: filename,
            localPath: relativePath,
            capturedAt: capturedAt,
            autoUpload: autoUpload
        )
        return SavedOTGPhoto(
            assetID: cameraObjectID,
            relativeLocalPath: relativePath,
            filename: filename,
            capturedAt: capturedAt
        )
    }
}