datasource.swift

import UIKit
import DataProvider

final class CurrentPlanDataSource: NSObject {

	// MARK: - Cell -

	enum Cell {
		case daysLeft(daysLeft: Int, endDate: Date, newPlan: String?, currentPlanTitle: String)
		case cancelDowngrade(previousPlanTitle: String)
		case module(CurrentPlan.Module)
		case paymentHistory
	}

	// MARK: - Properties -

	var planDetails: CurrentPlan? {
		didSet {
			updateCells()
		}
	}

	private(set) var cells: [Cell] = []

	// MARK: - Functions -
	// MARK: Private

	private func updateCells() {
		guard let planDetails = planDetails else {
			cells = []
			return
		}
		cells.removeAll()
		if let daysEnd = planDetails.daysLeft, let endDate = planDetails.endsAt {
			cells.append(.daysLeft(daysLeft: daysEnd, endDate: endDate, newPlan: planDetails.downgradingTo, currentPlanTitle: planDetails.title))
		}
		if let _ = planDetails.downgradingTo {
			cells.append(.cancelDowngrade(previousPlanTitle: planDetails.title))
		}
		planDetails.modules.forEach { moduleModel in
			cells.append(.module(moduleModel))
		}
		cells.append(.paymentHistory)
	}
}

extension CurrentPlanDataSource: UITableViewDataSource {

	// MARK: - UITableViewDataSource -

	func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
		cells.count
	}

	func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
		switch cells[indexPath.row] {
		case let .daysLeft(daysLeft, endDate, newPlan, currentPlan):
			let cell: DaysLeftTableViewCell = tableView.dequeueCell(for: indexPath)
			let viewModel = DaysLeftCellViewModel(daysLeft: daysLeft, endDate: endDate, planToTransition: newPlan, currentPlan: currentPlan)
			cell.configure(with: viewModel)
			return cell
		case .cancelDowngrade(let previousPlanTitle):
			let cell: CancelDowngradeTableViewCell = tableView.dequeueCell(for: indexPath)
			cell.configure(with: previousPlanTitle)
			return cell
		case .module(let model):
			let cell: CurrentPlanModuleTableViewCell = tableView.dequeueCell(for: indexPath)
			let viewModel = CurrentPlanModuleCellViewModel(module: model)
			cell.configure(with: viewModel)
			return cell
		case .paymentHistory:
			let cell: PlanPaymentHistoryTableViewCell = tableView.dequeueCell(for: indexPath)
			return cell
		}
	}
}