//
//  OfflineAssessmentViewModel.swift
//  LMS
//
//  Created by Suraj Kumar Mandal on 11/01/23.
//

import Foundation
import Alamofire

class OfflineAssessmentViewModel {
    
    var delegate: OfflineAssessmentProtocol?
    
    func downloadAssessment(fileId:String) {
        if let delegate = delegate {
            delegate.startLoader()
            let accessToken = UserDefaults.standard.value(forKey: "accessToken") as! String

            let url = ApiURL.DownloadBase64 + "/\(fileId)"
            print(url)
            
            let headers: HTTPHeaders = [
                "Authorization": "Bearer \(accessToken)",
                "Accept": "application/json",
                "Content-Type": "application/json"
            ]
            print(headers)
            
            AF.request(url, 
                       method: .get,
                       encoding: URLEncoding.httpBody,
                       headers: headers)
            .responseString { response in
                if response.response?.statusCode == 200 {
                    switch response.result {
                    case .success(_):
                        delegate.stopLoader()
                        let stringData = response.description.components(separatedBy: ",")
                        delegate.getDownloadedFile(base64:stringData[1])
                        break
                    case .failure(let error):
                        delegate.stopLoader()
                        print(error.localizedDescription)
                        delegate.showError(error: error.localizedDescription)
                        break
                    }
                } else {
                    print("Server error")
                }
            }
        }
    }
    
    func uploadAssessment(assessmentId:Int, userId:Int, fileType:String, docData:Data?) {
        if let delegate = delegate {
            delegate.startLoader()
            let accessToken = UserDefaults.standard.value(forKey: "accessToken") as! String

            let url = ApiURL.UploadAssessment
            print(url)
            
            let headers: HTTPHeaders = [
                "Authorization": "Bearer \(accessToken)",
                "Accept": "application/json",
                "Content-Type": "application/json"
            ]
            print(headers)
            
            let params: [String: Any] = [
                "assessmentId" : assessmentId,
                "userId" : userId,
                "fileType" : fileType
            ]
            print(params)
            
            let date = Date()
            let dateFormatter = DateFormatter()
            dateFormatter.dateFormat = "dd/MM/yyyy"
            print(dateFormatter.string(from: date))
            
            let imageKey = "file"
            let fileName = "assessment(\(assessmentId))-\(dateFormatter.string(from: date)).\(fileType)"
            
            AF.upload(multipartFormData: { multiPart in
                for (key, value) in (params ?? [:]) {
                    if let arrayObj = value as? [Any] {
                        for index in 0..<arrayObj.count {
                            multiPart.append("\(arrayObj[index])".data(using: .utf8)!, withName: "\(key)[\(index)]")
                        }
                    } else {
                        multiPart.append("\(value)".data(using: .utf8)!, withName: key)
                    }
                }
                multiPart.append(docData!, withName: imageKey, fileName: fileName, mimeType: "application/pdf")
            }, to: url, headers: headers).responseJSON { response in
                if response.response?.statusCode == 200 {
                    delegate.stopLoader()
                    delegate.showError(error: "Upload successfully.")
                    delegate.moveToAssessment()
                } else {
                    delegate.stopLoader()
                    if let dictionary = response.value as? [String:Any] {
                        let code = dictionary["code"] as? String
                        let message = dictionary["message"] as? String
                        
                        delegate.showError(error: message ?? "Answer not uploaded!")
                    }
                }
            }
            
        }
    }
    
}

protocol OfflineAssessmentProtocol {
    func startLoader()
    func stopLoader()
    func showError(error:String)
    func getDownloadedFile(base64:String)
    func moveToAssessment()
}