import Foundation
import VisionCamera

@objc
public class BaseMLKitPlugin: FrameProcessorPlugin {

  let proxy: VisionCameraProxyHolder
  let options: [AnyHashable: Any]?

  private let frameProcessInterval: Int
  private var frameCounter: Int = 0
  let invertColors: Bool
  let scaleFactor: CGFloat

  var outputOrientation: OutputOrientation?

  public override init(
    proxy: VisionCameraProxyHolder,
    options: [AnyHashable: Any]?
  ) {
    self.proxy = proxy
    self.options = options
    self.frameProcessInterval = options?["frameProcessInterval"] as? Int ?? 0
    self.invertColors = options?["invertColors"] as? Bool ?? false

    let sf = options?["scaleFactor"] as? NSNumber
    let sfValue = sf?.doubleValue ?? 1.0

    self.scaleFactor = min(max(CGFloat(sfValue), 0.9), 1.0)

    super.init(proxy: proxy, options: options)
  }

  public override func callback(
    _ frame: Frame,
    withArguments arguments: [AnyHashable: Any]?
  ) -> Any {
    // Extract outputOrientation from arguments for rotation support
    outputOrientation = OutputOrientation(
      string: arguments?["outputOrientation"] as? String
    )

    // Process 1 frame, skip N frames, repeat
    // Note: Consider using runAtTargetFps() from Vision Camera instead
    if frameProcessInterval > 0 {
      frameCounter += 1
      if frameCounter <= frameProcessInterval {
        return [:]
      }
      frameCounter = 0
    }

    do {
      return try processFrame(frame, withArguments: arguments)
    } catch {
      print("[\(pluginName)] Error occurred: \(error.localizedDescription)")
      return [:]
    }
  }

  public func processFrame(
    _ frame: Frame,
    withArguments arguments: [AnyHashable: Any]?
  ) throws -> [String: Any] {
    fatalError("processFrame must be overridden by subclass")
  }

  var pluginName: String {
    return String(describing: type(of: self))
  }
}