//
//  HorizontalScrolViewDelegate.swift
//  react-native-simple-grid
//
//  Created by Vittorio Cellucci on 2022-09-29.
//

import Foundation
class HorizontalScrollViewDelegate: NSObject, UIScrollViewDelegate {
  weak var tableView: TableView?
  weak var multiColumnTable: TableView?
  weak var totalsView: UIView?
  weak var headersView: UIView?
  weak var columnWidths: ColumnWidths?
  weak var grabber: ColumnResizerView?
  weak var containerView: ContainerView?
  var translateion = CGPoint.zero
  var width = 0.0
  var freezeFirstCol = false

  func captureFirstColumnWidth() {
    guard let columnWidths = self.columnWidths else { return }
    width = columnWidths.columnWidths[0]
  }

  func scrollViewDidScroll(_ scrollView: UIScrollView) {
    guard let columnWidths = self.columnWidths else { return }
    guard let tableView = self.tableView else { return }
    guard let grabber = self.grabber else { return }
    guard let containerView = self.containerView else { return }

    let totalWidth = columnWidths.getTotalWidth()
    let shadowOffsetX = clampScrollPos(Float(scrollView.contentOffset.x))
    let rawX = scrollView.contentOffset.x
    var right = max(abs(scrollView.frame.width  -  totalWidth) - rawX, 0)
    if totalWidth < Double(containerView.frame.width) {
      right = 2
    }

    if rawX >= 0 {
      tableView.dataCollectionView?.childCollectionView?.scrollIndicatorInsets.right = right
      multiColumnTable?.dataCollectionView?.childCollectionView?.scrollIndicatorInsets.right = right
    }
    if freezeFirstCol {
      if rawX <= 0 {
        let x = width - rawX
        tableView.setWidth(x)
        grabber.setPosition(x)
        containerView.testTruncation()
      }
      let offset = shadowOffsetX/100.0
      updateShadow(offset: offset)
    } else {
      tableView.horizontalScrollOffset(rawX)
    }
    multiColumnTable?.horizontalScrollOffset(rawX)

  }

  func clampScrollPos(_ x: Float) -> Float {
    return min(100.0, x)
  }

  func updateShadow(offset: Float) {
    tableView?.setShadow(offset: min(offset, 0.4))
    tableView?.setNeedsDisplay()
  }

  func updateVScroll() {

  }
}