//
//  LearningModulesViewController.swift
//  Learn Genie
//
//  Created by Suraj Kumar Mandal on 13/09/21.
//

import UIKit
import SideMenu

class LearningModulesViewController: UIViewController {
    
    @IBOutlet var learningModuleTableView: UITableView!
    @IBOutlet var navigationBar: UINavigationBar!
    @IBOutlet var optionView: UIView!
    @IBOutlet var topicHeadingLabel: UILabel!
    @IBOutlet var topicsTableView: UITableView!
    @IBOutlet var topicsTableHeightConstraint: NSLayoutConstraint!
    
    let levelData = DBManager.sharedInstance.database.objects(LevelModel.self)
    var index = 0
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Do any additional setup after loading the view.
        learningModuleTableView.delegate = self
        learningModuleTableView.dataSource = self
        learningModuleTableView.tableFooterView = UIView()
        
        topicsTableView.delegate = self
        topicsTableView.dataSource = self
        topicsTableView.tableFooterView = UIView()
        topicsTableView.layer.cornerRadius = 15
        
        optionView.isHidden = true
        
        print(levelData.count)
        for level in levelData {
            if level.name != "Introduction" {
                print("Level name: \(level.name)")
            }
        }
    }
    
    override func viewWillAppear(_ animated: Bool) {
        learningModuleTableView.reloadData()
        topicsTableView.reloadData()
        self.topicsTableView.layoutIfNeeded()
        self.topicsTableView.heightAnchor.constraint(equalToConstant: self.topicsTableView.contentSize.height).isActive = true
        navigationBar.topItem?.title = Helper.translateText(inputText: "Learning Modules")
    }
    
    func convertBytesToImage(byteString: String) -> UIImage? {
        let strings = byteString.components(separatedBy: ",")
        var bytes = [UInt8]()
        for i in 0..<strings.count {
            if let signedByte = Int8(strings[i]) {
                bytes.append(UInt8(bitPattern: signedByte))
            } else {
                // Do something with this error condition
            }
        }
        let imageData: NSData = NSData(bytes: bytes, length: bytes.count)
        return UIImage(data: imageData as Data)
    }
    
    func getTopicName(id:Int) -> String {
        let topicData = DBManager.sharedInstance.database.objects(TopicModel.self)
        var name = ""
        for item in topicData {
            if id == item.id {
                name = item.name
                break
            }
        }
        return name
    }
    
    /*
     // MARK: - Navigation
     
     // In a storyboard-based application, you will often want to do a little preparation before navigation
     override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
     // Get the new view controller using segue.destination.
     // Pass the selected object to the new view controller.
     }
     */
    
    @IBAction func menuNavAction(_ sender: Any) {
        let menu = storyboard!.instantiateViewController(withIdentifier: "SideMenuNavigationController") as! SideMenuNavigationController
        present(menu, animated: true, completion: nil)
    }
    
    @IBAction func dismissOptionViewAction(_ sender: Any) {
        optionView.isHidden = true
    }
}

extension LearningModulesViewController: UITableViewDelegate, UITableViewDataSource {
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        if tableView == learningModuleTableView {
            return levelData.count
        } else {
            print("Index: \(index)")
            print("Count: \(levelData[index])")
            return levelData[index].topics.count
        }
    }
    
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        if tableView == learningModuleTableView {
            guard let cell = tableView.dequeueReusableCell(withIdentifier: "LearningModulesTableViewCell", for: indexPath) as? LearningModulesTableViewCell else {
                return UITableViewCell()
            }
            if levelData[indexPath.row].name == "Introduction" {
                cell.isHidden = true
            } else {
                cell.headLabel.text = Helper.translateText(inputText: levelData[indexPath.row].name)
                cell.contentLabel.text = Helper.translateText(inputText: Constant.learningModuleContentArray[indexPath.row])
                let strFetched = levelData[indexPath.row].iconBytes
                cell.itemImageView.image = convertBytesToImage(byteString: strFetched)
            }
            return cell
        } else {
            guard let cell = tableView.dequeueReusableCell(withIdentifier: "OptionsTableViewCell", for: indexPath) as? OptionsTableViewCell else {
                return UITableViewCell()
            }
            cell.optionTitleLabel.text = Helper.translateText(inputText: getTopicName(id: levelData[index].topics[indexPath.row].id))
            return cell
        }
    }
    
    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        DispatchQueue.main.async { [self] in
            if tableView == learningModuleTableView {
                self.index = indexPath.row
                self.topicHeadingLabel.text = Helper.translateText(inputText:  levelData[index].name)
                topicsTableView.reloadData()
                optionView.isHidden = false
            } else {
                let introVC = self.storyboard?.instantiateViewController(withIdentifier: "IntroductionViewController") as! IntroductionViewController
                introVC.topicName = getTopicName(id: levelData[index].topics[indexPath.row].id)
                introVC.topicId = levelData[index].topics[indexPath.row].id
                introVC.mainTopicIndex = index
                introVC.topicIndex = indexPath.row
                
                self.navigationController?.pushViewController(introVC, animated: false)
            }
        }
    }
    
    func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
        var rowHeight:CGFloat = 0.0
        
        if tableView == learningModuleTableView {
            if levelData[indexPath.row].name == "Introduction" {
                rowHeight = 0.0
            } else {
                rowHeight = 160.0    //or whatever you like
            }
        } else {
            rowHeight = UITableView.automaticDimension
        }
        
        return rowHeight
    }
    
    func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
        if tableView == learningModuleTableView {
            
        } else {
            self.topicsTableHeightConstraint.constant = self.topicsTableView.contentSize.height
            tableView.layoutIfNeeded()
        }
    }
}