//
//  ViewController.swift
//  MVMCoreUI
//
//  Created by Scott Pfeil on 11/5/19.
//  Copyright © 2019 Verizon Wireless. All rights reserved.
//

import UIKit

@objcMembers open class ViewController: UIViewController, MVMCoreViewControllerProtocol {
    public var pageType: String?
    public var loadObject: MVMCoreLoadObject?
    public var pageModel: PageModelProtocol?

    // MARK:  Response handling
    public func shouldFinishProcessingLoad(_ loadObject: MVMCoreLoadObject, error: AutoreleasingUnsafeMutablePointer<MVMCoreErrorObject>) -> Bool {
        pageType = loadObject.pageType
        self.loadObject = loadObject
        
        // Parse the model for the page.
        do {
            try parsePageJSON()
        } catch let parsingError {
            // Log all parsing errors and fail load.
            if let errorObject = MVMCoreErrorObject.createErrorObject(for: parsingError, location: MVMCoreLoadHandler.sharedGlobal()?.errorLocation(forRequest: loadObject)) {
                errorObject.messageToDisplay = MVMCoreGetterUtility.hardcodedString(withKey: HardcodedErrorUnableToProcess)
                error.pointee = errorObject
            }
            return false
        }

        // Verifies all modules needed are loaded.
        return MFViewController.verifyRequiredModulesLoaded(for: loadObject, error: error)
    }
    
    @objc func parsePageJSON() throws {
    }

    public class func verifyRequiredModulesLoaded(for loadObject: MVMCoreLoadObject?, error: inout MVMCoreErrorObject?) -> Bool {
        guard let pageType = loadObject?.pageType, var modulesRequired = MVMCoreUIViewControllerMappingObject.shared()?.modulesRequired(forPageType: pageType) else { return true }

        guard let loadedModules = loadObject?.modulesJSON else { return false }

        for case let key as String in Array(loadedModules.keys) {
            guard modulesRequired.count > 0 else { break }
            if let index = modulesRequired.firstIndex(where: {($0 as? String) == key}) {
                modulesRequired.remove(at: index)
            }
        }

        guard modulesRequired.count == 0 else {
            if error != nil {
                error = MVMCoreErrorObject(title: nil, message: MVMCoreGetterUtility.hardcodedString(withKey: HardcodedErrorCritical), messageToLog: modulesRequired.description, code: ErrorCode.requiredModuleNotPresent.rawValue, domain: ErrorDomainNative, location: MVMCoreLoadHandler.sharedGlobal()?.errorLocation(forRequest: loadObject!))
            }
            return false
        }
        return true
    }
    
    open func setNavigationItem() {
        navigationItem.title = pageModel?.screenHeading
        navigationItem.accessibilityLabel = pageModel?.screenHeading 
    }

    open func newDataBuildScreen() {
        // TODO atomize the navigation item
        setNavigationItem()
    }

    open func initialLoad() {
    }

    open func updateViews() {
    }

    override open func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.
    }
}