//
//  Repeater.swift
//  lottie-swift
//
//  Created by Brandon Withrow on 1/8/19.
//

import Foundation

/// An item that define an ellipse shape
final class Repeater: ShapeItem {

  // MARK: Lifecycle

  required init(from decoder: Decoder) throws {
    let container = try decoder.container(keyedBy: Repeater.CodingKeys.self)
    copies = try container.decodeIfPresent(KeyframeGroup<Vector1D>.self, forKey: .copies) ?? KeyframeGroup(Vector1D(0))
    offset = try container.decodeIfPresent(KeyframeGroup<Vector1D>.self, forKey: .offset) ?? KeyframeGroup(Vector1D(0))
    let transformContainer = try container.nestedContainer(keyedBy: TransformKeys.self, forKey: .transform)
    startOpacity = try transformContainer
      .decodeIfPresent(KeyframeGroup<Vector1D>.self, forKey: .startOpacity) ?? KeyframeGroup(Vector1D(100))
    endOpacity = try transformContainer
      .decodeIfPresent(KeyframeGroup<Vector1D>.self, forKey: .endOpacity) ?? KeyframeGroup(Vector1D(100))
    rotation = try transformContainer
      .decodeIfPresent(KeyframeGroup<Vector1D>.self, forKey: .rotation) ?? KeyframeGroup(Vector1D(0))
    position = try transformContainer
      .decodeIfPresent(KeyframeGroup<Vector3D>.self, forKey: .position) ?? KeyframeGroup(Vector3D(x: Double(0), y: 0, z: 0))
    anchorPoint = try transformContainer
      .decodeIfPresent(KeyframeGroup<Vector3D>.self, forKey: .anchorPoint) ?? KeyframeGroup(Vector3D(x: Double(0), y: 0, z: 0))
    scale = try transformContainer
      .decodeIfPresent(KeyframeGroup<Vector3D>.self, forKey: .scale) ?? KeyframeGroup(Vector3D(x: Double(100), y: 100, z: 100))
    try super.init(from: decoder)
  }

  // MARK: Internal

  /// The number of copies to repeat
  let copies: KeyframeGroup<Vector1D>

  /// The offset of each copy
  let offset: KeyframeGroup<Vector1D>

  /// Start Opacity
  let startOpacity: KeyframeGroup<Vector1D>

  /// End opacity
  let endOpacity: KeyframeGroup<Vector1D>

  /// The rotation
  let rotation: KeyframeGroup<Vector1D>

  /// Anchor Point
  let anchorPoint: KeyframeGroup<Vector3D>

  /// Position
  let position: KeyframeGroup<Vector3D>

  /// Scale
  let scale: KeyframeGroup<Vector3D>

  override func encode(to encoder: Encoder) throws {
    try super.encode(to: encoder)
    var container = encoder.container(keyedBy: CodingKeys.self)
    try container.encode(copies, forKey: .copies)
    try container.encode(offset, forKey: .offset)
    var transformContainer = container.nestedContainer(keyedBy: TransformKeys.self, forKey: .transform)
    try transformContainer.encode(startOpacity, forKey: .startOpacity)
    try transformContainer.encode(endOpacity, forKey: .endOpacity)
    try transformContainer.encode(rotation, forKey: .rotation)
    try transformContainer.encode(position, forKey: .position)
    try transformContainer.encode(anchorPoint, forKey: .anchorPoint)
    try transformContainer.encode(scale, forKey: .scale)
  }

  // MARK: Private

  private enum CodingKeys: String, CodingKey {
    case copies = "c"
    case offset = "o"
    case transform = "tr"
  }

  private enum TransformKeys: String, CodingKey {
    case rotation = "r"
    case startOpacity = "so"
    case endOpacity = "eo"
    case anchorPoint = "a"
    case position = "p"
    case scale = "s"
  }
}
