//
//  ChatMoreMenuView.swift
//  yinmeng-ios
//
//  Created by MaiMang on 2024/2/29.
//

import UIKit

enum ChatMoreMenuType: Int {
	case album = 1001
	case camera = 1002
}

/// 行数
fileprivate let kRowNumber = 2
/// 列数
fileprivate let kColumnNumber = 4

fileprivate let kMoreMenuCellNumberOfOnePage = kRowNumber * kColumnNumber

protocol ChatMoreMenuViewDelegate {
	/// 获取选择的菜单
	func menu(_ view: ChatMoreMenuView, DidSelected type: ChatMoreMenuType)
}

extension ChatMoreMenuViewDelegate {

	func menu(_ view: ChatMoreMenuView, DidSelected type: ChatMoreMenuType) {}
}

class ChatMoreMenuView: UIView {

	// MARK: - lazy var

	var delegate: ChatMoreMenuViewDelegate?

	/// 隐藏分页指示器
	var hidePageController: Bool = false {
		didSet {
			self.pageControl.alpha = self.hidePageController ? 0.0 : 1.0
			UIView.animate(withDuration: 0.15, delay: 0, options: .curveEaseOut, animations: {
				self.pageControl.isHidden = self.hidePageController
			}, completion: nil)

			self.collectionView.scrollToItem(at: IndexPath(row: 0, section: 0), at: .centeredHorizontally, animated: false)
		}
	}

	var pageIndicatorTintColor: UIColor? {
		didSet {
			guard pageIndicatorTintColor != nil else {
				return
			}
			pageControl.pageIndicatorTintColor = pageIndicatorTintColor
		}
	}

	var currentPageIndicatorTintColor: UIColor? {
		didSet {
			guard currentPageIndicatorTintColor != nil else {
				return
			}
			pageControl.currentPageIndicatorTintColor = currentPageIndicatorTintColor
		}
	}

	lazy var dataSource: [ChatMoreMnueConfig] = {
		let configs = [
			ChatMoreMnueConfig(title: "图片", image: "chat_more_album", type: .album),
		]
		return configs
	}()

	lazy var collectionView: UICollectionView = {
		let layout = ChatKeyboardFlowLayout(column: kColumnNumber, row: kRowNumber)
		// collectionView
		let collection = UICollectionView(frame: self.bounds, collectionViewLayout: layout)
		collection.backgroundColor = ThemeColor(hexStr: "#F8F8F8")
		collection.register(cellType: ChatMoreMenuCell.self)
		collection.showsHorizontalScrollIndicator = true
		collection.showsVerticalScrollIndicator = true
		collection.dataSource = self
		collection.delegate = self
		collection.isPagingEnabled = true
		return collection
	}()

	lazy var pageControl: UIPageControl = {
		let pager = UIPageControl()
		pager.backgroundColor = .clear
		pager.pageIndicatorTintColor = .white
		pager.currentPageIndicatorTintColor = ThemeColor(hexStr: "#000000")
		pager.currentPage = 0
		pager.isHidden = true
		pager.numberOfPages = self.dataSource.count / kMoreMenuCellNumberOfOnePage + (self.dataSource.count % kMoreMenuCellNumberOfOnePage == 0 ? 0 : 1)
		return pager
	}()

	// MARK: - life cycle

	override init(frame: CGRect) {
		super.init(frame: frame)

		makeUI()
		reloadData()
	}

	required init?(coder aDecoder: NSCoder) {
		super.init(coder: aDecoder)

		makeUI()
		reloadData()
	}

	func makeUI() {
		self.backgroundColor = ThemeColor(hexStr: "#F8F8F8")

		addSubview(pageControl)
		addSubview(collectionView)

		pageControl.snp.makeConstraints { make in
			make.bottom.equalToSuperview().offset(-SafeAraeBottomHeight)
			make.centerX.equalToSuperview()
			make.height.equalTo(30)
		}

		collectionView.snp.makeConstraints { make in
			make.top.left.right.equalToSuperview()
			make.bottom.equalTo(pageControl.snp.top)
		}
	}

	open func reloadData() {
		self.needsUpdateConstraints()
		self.layoutIfNeeded()

		UIView.animate(withDuration: 0.15, delay: 0, options: .curveEaseOut, animations: {
			self.pageControl.alpha = 1.0
			self.pageControl.isHidden = self.dataSource.count > 8 ? false : true
		}, completion: nil)

		DispatchQueue.main.async {
			self.collectionView.reloadData()
		}
	}
}


// MARK: - UICollectionViewDataSource

extension ChatMoreMenuView: UICollectionViewDataSource {

	func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
		return dataSource.count
	}

	func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
		let cell = collectionView.dequeueReusableCell(for: indexPath, cellType: ChatMoreMenuCell.self)
		if let model = dataSource[safe: indexPath.row] {
			cell.model = model
		}
		return cell
	}

}

// MARK: - UICollectionViewDelegate

extension ChatMoreMenuView: UICollectionViewDelegate {

	func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
		if let model = dataSource[safe: indexPath.row] {
			delegate?.menu(self, DidSelected: model.type!)
		}
	}
}

extension ChatMoreMenuView {

	func scrollViewDidScroll(_ scrollView: UIScrollView) {
		if scrollView == collectionView {
			let offsetX = scrollView.contentOffset.x
			let index = offsetX / ScreenWidth
			pageControl.currentPage = Int(index)
		}
	}
}

			class ChatKeyboardFlowLayout: UICollectionViewFlowLayout {
				// 保存所有item
				fileprivate var attributesArr: [UICollectionViewLayoutAttributes] = []
				fileprivate var col: Int = 0
				fileprivate var row: Int = 0

				init(column: Int, row: Int) {
					super.init()
					self.col = column
					self.row = row
				}

				required init?(coder aDecoder: NSCoder) {
					fatalError("init(coder:) has not been implemented")
				}

				// MARK: - 重新布局
				override func prepare() {
					super.prepare()

					let itemWH: CGFloat = ScreenWidth / CGFloat(col)

					// 设置itemSize
					itemSize = CGSize(width: itemWH, height: itemWH)
					minimumLineSpacing = 0
					minimumInteritemSpacing = 0
					scrollDirection = .horizontal

					// 设置collectionView属性
					collectionView?.isPagingEnabled = true
					collectionView?.showsHorizontalScrollIndicator = false
					collectionView?.showsVerticalScrollIndicator = true
					let insertMargin = (collectionView!.bounds.height - CGFloat(row) * itemWH) * 0.5
					collectionView?.contentInset = UIEdgeInsets(top: insertMargin, left: 0, bottom: insertMargin, right: 0)

					var page = 0
					let itemsCount = collectionView?.numberOfItems(inSection: 0) ?? 0
					for itemIndex in 0..<itemsCount {
						let indexPath = IndexPath(item: itemIndex, section: 0)
						let attributes = UICollectionViewLayoutAttributes(forCellWith: indexPath)

						page = itemIndex / (col * row)
						// 通过一系列计算, 得到x, y值
						let x = itemSize.width * CGFloat(itemIndex % Int(col)) + (CGFloat(page) * ScreenWidth)
						let y = itemSize.height * CGFloat((itemIndex - page * row * col) / col)

						attributes.frame = CGRect(x: x, y: y, width: itemSize.width, height: itemSize.height)
						// 把每一个新的属性保存起来
						attributesArr.append(attributes)
					}

				}

				override func layoutAttributesForElements(in rect: CGRect) -> [UICollectionViewLayoutAttributes]? {
					var rectAttributes: [UICollectionViewLayoutAttributes] = []
					_ = attributesArr.map({
						if rect.contains($0.frame) {
							rectAttributes.append($0)
						}
					})
					return rectAttributes
				}

				override var collectionViewContentSize: CGSize {
					let size: CGSize = super.collectionViewContentSize
					let collectionViewWidth: CGFloat = self.collectionView!.frame.size.width
					let nbOfScreen: Int = Int(ceil(size.width / collectionViewWidth))
					let newSize: CGSize = CGSize(width: collectionViewWidth * CGFloat(nbOfScreen), height: size.height)
					return newSize
				}
			}