vds_ios/VDS/Components/Table/Table.swift

//
//  Table.swift
//  VDS
//
//  Created by Nadigadda, Sumanth on 24/04/24.
//

import Foundation
import UIKit
import VDSTokens

@objc(VDSTable)
open class Table: View {
    
    //--------------------------------------------------
    // MARK: - Private Properties
    //--------------------------------------------------
        
    private lazy var matrixView = SelfSizingCollectionView(frame: .zero, collectionViewLayout: flowLayout).with {
        $0.register(TableCellItem.self, forCellWithReuseIdentifier: TableCellItem.Identifier)
        $0.dataSource = self
        $0.delegate = self
        $0.translatesAutoresizingMaskIntoConstraints = false
        $0.allowsSelection = false
        $0.isScrollEnabled = false
        $0.showsVerticalScrollIndicator = false
        $0.showsHorizontalScrollIndicator = false
        $0.isAccessibilityElement = true
        $0.backgroundColor = .clear
    }
    
    private let flowLayout = MatrixFlowLayout().with {
        $0.estimatedItemSize = UICollectionViewFlowLayout.automaticSize
        $0.minimumLineSpacing = 0
        $0.minimumInteritemSpacing = 0
    }

    //--------------------------------------------------
    // MARK: - Enums
    //--------------------------------------------------
    
    public enum Padding: String, CaseIterable {
        case standard, compact
        
        func horizontalValue() -> CGFloat {
            switch self {
            case .standard:
                return UIDevice.isIPad ? VDSLayout.space8X : VDSLayout.space6X
            case .compact:
                return UIDevice.isIPad ? VDSLayout.space8X : VDSLayout.space6X
            }
        }
        
        func verticalValue() -> CGFloat {
            switch self {
            case .standard:
                return UIDevice.isIPad ? VDSLayout.space8X : VDSLayout.space6X
            case .compact:
                return UIDevice.isIPad ? VDSLayout.space4X : VDSLayout.space3X
            }
        }
    }
    
    //--------------------------------------------------
    // MARK: - Public Properties
    //--------------------------------------------------
    
    open var striped: Bool = false { didSet { setNeedsUpdate() } }
    
    open var padding: Padding = .standard { didSet { setNeedsUpdate() } }
    
    open var headerBottomLine: Bool = false { didSet { setNeedsUpdate() } }
    
    open var rowBottomLine: Bool = false { didSet { setNeedsUpdate() } }
    
    open var headerBottomLineType: Line.Style = .primary { didSet { setNeedsUpdate() } }
    
    open var rowBottomLineType: Line.Style = .secondary { didSet { setNeedsUpdate() } }
    
    open var tableData: [[TableCellModel]]? { didSet { setNeedsUpdate() } }
    
    //--------------------------------------------------
    // MARK: - Overrides
    //--------------------------------------------------
    
    open override func initialSetup() {
        super.initialSetup()
        addSubview(matrixView)
        matrixView.pinToSuperView()
    }
    
    open override func updateView() {
        super.updateView()
        matrixView.reloadData()
    }
}

extension Table : UICollectionViewDelegate, UICollectionViewDataSource {
    
    public func numberOfSections(in collectionView: UICollectionView) -> Int {
        return tableData?.count ?? 0
    }
    public func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return tableData?[section].count ?? 0
    }
    
    public func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        guard let cell = collectionView.dequeueReusableCell(withReuseIdentifier: TableCellItem.Identifier, for: indexPath) as? TableCellItem,
              let currentItem = tableData?[indexPath.section][indexPath.row]
        else { return UICollectionViewCell() }
        let shouldStrip = striped ? (indexPath.section % 2 != 0) : false
        let style = indexPath.section == 0 ? headerBottomLineType : rowBottomLineType
        let hideSeparator = indexPath.section == 0 ? headerBottomLine : rowBottomLine
        cell.updateCell(content: currentItem, surface: surface, separatorStyle: style, isHeader: indexPath.section == 0, hideSeparator: hideSeparator, striped: shouldStrip, padding: padding)
        return cell
    }
}

extension Table: UICollectionViewDelegateFlowLayout {
    
    public func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
        guard let sectionCount = tableData?[indexPath.section].count else { return CGSize.zero }
        let width = Int(collectionView.frame.width) / sectionCount
        return CGSize(width: width, height: 100)
    }
}

final class MatrixFlowLayout : UICollectionViewFlowLayout {
    
    override func layoutAttributesForElements(in rect: CGRect) -> [UICollectionViewLayoutAttributes]? {
        guard let layoutAttributesObjects = super.layoutAttributesForElements(in: rect) else { return nil }
        layoutAttributesObjects.forEach({ layoutAttributes in
            if layoutAttributes.representedElementCategory == .cell,
               let newFrame = layoutAttributesForItem(at: layoutAttributes.indexPath)?.frame  {
                layoutAttributes.frame = newFrame
            }
        })
        return layoutAttributesObjects
    }

    override func layoutAttributesForItem(at indexPath: IndexPath) -> UICollectionViewLayoutAttributes? {
        guard let collectionView = collectionView,
              let layoutAttributes = super.layoutAttributesForItem(at: indexPath) else { return nil }
        let itemsCount = CGFloat(collectionView.numberOfItems(inSection: indexPath.section))
        layoutAttributes.frame.size.width = ceil(collectionView.safeAreaLayoutGuide.layoutFrame.width / itemsCount)
        return layoutAttributes
    }
}