//
//  ChatController.swift
//  OnlineChatSdk
//
//  Created by Andrew Blinov on 22/03/2019.
//  Copyright © 2019 Andrew Blinov. All rights reserved.
//

import UIKit
import WebKit
import AVFoundation

open class ChatController: UIViewController, WKNavigationDelegate, WKScriptMessageHandler {

    public static let event_operatorSendMessage = "operatorSendMessage"
    public static let event_clientSendMessage = "clientSendMessage"
    public static let event_clientMakeSubscribe = "clientMakeSubscribe"
    public static let event_contactsUpdated = "contactsUpdated"
    public static let event_sendRate = "sendRate"
    public static let event_clientId = "clientId"
    public static let event_closeSupport = "closeSupport"
    
    public static let method_setClientInfo = "setClientInfo"
    public static let method_setTarget = "setTarget"
    public static let method_openReviewsTab = "openReviewsTab"
    public static let method_openTab = "openTab"
    public static let method_sendMessage = "sendMessage"
    public static let method_receiveMessage = "receiveMessage"
    public static let method_setOperator = "setOperator"
    public static let method_getContacts = "getContacts"
    private static let method_destroy = "destroy"
    
    public var chatView: WKWebView!
    private var callJs: Array<String>!
    private var didFinish: Bool = false
    private var widgetUrl: String = ""

    private static func getUnreadedMessagesCallback(_ result: NSDictionary) -> NSDictionary {
        let resultWrapper = ChatApiMessagesWrapper(result)
        if resultWrapper.getMessages().count == 0 {
            return resultWrapper.getResult()
        }
        var unreadedMessages: Array<NSDictionary> = []
        for message: NSDictionary in resultWrapper.getMessages() as! Array<NSDictionary> {
            if message.value(forKey: "isVisibleForClient") != nil {
                if (message.value(forKey: "isVisibleForClient") as! Int) == 1 {
                    unreadedMessages.append(message)
                }
            }
        }
        if unreadedMessages.count == 0 {
            return resultWrapper.getResult()
        }
        resultWrapper.setMessages(unreadedMessages as NSArray)
        return resultWrapper.getResult()
    }

    private static func getUnreadedMessages(_ startDate: String, _ clientId: String, _ token: String, callback: @escaping (NSDictionary?) -> Void) {
        if token == "" {
            callback([
                "success": false,
                "error": [
                    "code": 0,
                    "descr": "Не задан token"
                ]
            ])
        }
        if clientId == "" {
            callback([
                "success": false,
                "error": [
                    "code": 0,
                    "descr": "Не задан clientId"
                ]
            ])
        }
        ChatApi().messages(token, params: [
            "client": [
                "clientId": clientId
            ],
            "sender": "operator",
            "status": "unreaded",
            "dateRange": [
                "start": startDate,
                "stop": ChatDateFormatter().getCurrent()
            ]
        ] as [String: Any], callback: {(result) in
            callback( ChatController.getUnreadedMessagesCallback(result!) )
        })
    }

    public static func getUnreadedMessages(clientId: String, token: String, callback: @escaping (NSDictionary?) -> Void) {
        let startDate = ChatDateFormatter().string(from: Date(timeIntervalSince1970: TimeInterval(Int(NSDate().timeIntervalSince1970) - 86400 * 14)))
        ChatController.getUnreadedMessages(startDate, clientId, token, callback: callback)
    }

    public static func getUnreadedMessages(callback: @escaping (NSDictionary?) -> Void) {
        let startDate = ChatDateFormatter().string(from: Date(timeIntervalSince1970: TimeInterval(Int(NSDate().timeIntervalSince1970) - 86400 * 14)))
        ChatController.getUnreadedMessages(startDate, ChatConfig.getClientId(), ChatConfig.getApiToken(), callback: callback)
    }

    private static func getNewMessagesCallback(_ result: NSDictionary) -> NSDictionary {
        let resultWrapper = ChatApiMessagesWrapper(result)
        if resultWrapper.getMessages().count == 0 {
            return resultWrapper.getResult()
        }
        let lastMessage = resultWrapper.getMessages()[resultWrapper.getMessages().count - 1] as! NSDictionary
        let lastDate = ChatDateFormatter().date(from: lastMessage["dateTime"] as! String)
        let nextDate = Date(timeIntervalSince1970: TimeInterval( Int(lastDate!.timeIntervalSince1970) + 1 ))
        ChatConfig.setLastDateTimeNewMessage( ChatDateFormatter().string(from: nextDate) )
        return resultWrapper.getResult()
    }

    public static func getNewMessages(clientId: String, token: String, callback: @escaping (NSDictionary?) -> Void) {
        let startDate = ChatConfig.getLastDateTimeNewMessage()
        if startDate == "" {
            self.getUnreadedMessages(clientId: clientId, token: token, callback: {(result) in
                callback( ChatController.getNewMessagesCallback(result!) )
            })
        } else {
            self.getUnreadedMessages(startDate, clientId, token, callback: {(result) in
                callback( ChatController.getNewMessagesCallback(result!) )
            })
        }
    }

    public static func getNewMessages(callback: @escaping (NSDictionary?) -> Void) {
        self.getNewMessages(clientId: ChatConfig.getClientId(), token: ChatConfig.getApiToken(), callback: {(result) in
            callback( ChatController.getNewMessagesCallback(result!) )
        })
    }

    override public func loadView() {
        let contentController = WKUserContentController()
        contentController.add(self, name: "chatInterface")

        let preferences = WKPreferences()
        preferences.javaScriptEnabled = true
        preferences.javaScriptCanOpenWindowsAutomatically = true

        let config = WKWebViewConfiguration()
        config.userContentController = contentController
        config.preferences = preferences

        var frame = UIScreen.main.bounds
        if parent != nil && parent?.view != nil && parent?.view.bounds != nil {
            frame = (parent?.view.bounds)!
        }
        chatView = WKWebView(frame: frame, configuration: config)
        chatView.navigationDelegate = self
        view = chatView
    }

    public func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
        didFinish = true
        if callJs != nil && !callJs.isEmpty {
            for script in callJs {
                callJs(script)
            }
            callJs = nil
        }
    }

    public func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> ()) {
        if let _ = navigationAction.request.url?.host {
            if (navigationAction.request.url?.absoluteString.contains(self.widgetUrl))! {
                decisionHandler(.allow)
                return
            }
        }
        decisionHandler(.cancel)
        onLinkPressed(url: navigationAction.request.url!)
    }

    private func getCallJsMethod(_ name: String, params: Array<Any>) -> String {
        var res: String = "window.MeTalk('"
        res.append(name)
        res.append("'")
        if params.count > 0 {
            for p in params {
                res.append(",")
                if p is Int {
                    res.append(String(describing: p))
                } else if p is Command {
                    res.append((p as! Command).command)
                } else {
                    res.append("'")
                    res.append(String(describing: p))
                    res.append("'")
                }
            }
        }
        res.append(")")
        return res
    }
    
    private func callJs(_ script: String) {
        chatView.evaluateJavaScript(script)
    }
    
    private func toJson(_ jsonObj: AnyObject) -> String {
        var data:Data? = nil
        do {
            data = try JSONSerialization.data(withJSONObject: jsonObj, options: JSONSerialization.WritingOptions());
        } catch {}
        if data != nil {
            return NSString(data: data!, encoding: String.Encoding.utf8.rawValue)! as String
        }
        return "{}"
    }
    
    public func load(_ id: String, _ domain: String, _ language: String = "", _ clientId: String = "", _ apiToken: String = "", _ showCloseButton: Bool = true) {
        if apiToken != "" {
            ChatConfig.setApiToken(apiToken)
        }
        var setup: Dictionary<String, Any> = [:]
        if !language.isEmpty {
            setup["language"] = language
        }
        if !clientId.isEmpty {
            setup["clientId"] = clientId
        }
        widgetUrl = "https://admin.verbox.ru/support/chat/\(id)/\(domain)"
        var url = URL(string: widgetUrl)
        if url == nil {
            var encodeDomain = String(describing: domain.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed))
            encodeDomain = encodeDomain.replacingOccurrences(of: "Optional(\"", with: "")
            encodeDomain = encodeDomain.replacingOccurrences(of: "\")", with: "")
            widgetUrl = "https://admin.verbox.ru/support/chat/\(id)/\(encodeDomain)"
            url = URL(string: widgetUrl)
        }
        var urlComponents = URLComponents(url: url!, resolvingAgainstBaseURL: false)
        if !setup.isEmpty {
            if (showCloseButton) {
                urlComponents?.queryItems = [
                    URLQueryItem(name: "setup", value: toJson(setup as AnyObject)),
                    URLQueryItem(name: "sdk-show-close-button", value: "1")
                ]
            } else {
                urlComponents?.queryItems = [
                    URLQueryItem(name: "setup", value: toJson(setup as AnyObject))
                ]
            }
        } else {
            if (showCloseButton) {
                urlComponents?.queryItems = [
                    URLQueryItem(name: "sdk-show-close-button", value: "1")
                ]
            }
        }
        url = urlComponents!.url!
        if url == nil {
            url = URL(string: widgetUrl)
        }
        chatView.load(URLRequest(url: url!))
        chatView.allowsBackForwardNavigationGestures = true
    }
    
    public func callJsMethod(_ name: String, params: Array<Any>) {
        if didFinish {
            callJs(getCallJsMethod(name, params: params))
        } else {
            if callJs == nil {
                callJs = []
            }
            callJs.append(getCallJsMethod(name, params: params))
        }
    }
    
    public func callJsSetClientInfo(_ jsonInfo: String) {
        callJsMethod(ChatController.method_setClientInfo, params: [Command(jsonInfo)])
    }
    
    public func callJsSetTarget(_ reason: String) {
        callJsMethod(ChatController.method_setTarget, params: [reason])
    }
    
    public func callJsOpenReviewsTab() {
        callJsMethod(ChatController.method_openReviewsTab, params: [])
    }
    
    public func callJsOpenTab(_ index: Int) {
        callJsMethod(ChatController.method_openTab, params: [index])
    }
    
    public func callJsSendMessage(_ text: String) {
        callJsMethod(ChatController.method_sendMessage, params: [text])
    }
    
    public func callJsReceiveMessage(_ text: String, _ oper: String, _ simulateTyping: Int) {
        callJsMethod(ChatController.method_receiveMessage, params: [text, oper, simulateTyping])
    }
    
    public func callJsSetOperator(_ login: String) {
        callJsMethod(ChatController.method_setOperator, params: [login])
    }
    
    public func callJsGetContacts() {
        callJsMethod(ChatController.method_getContacts, params: [Command("window.getContactsCallback")])
    }

    private func callJsDestroy() {
        callJsMethod(ChatController.method_destroy, params: [])
    }
    
    public func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
        if message.name != "chatInterface" {
            return
        }
        let jsonBody = (message.body as! String).data(using: .utf8)!
        let body = try? (JSONSerialization.jsonObject(with: jsonBody, options: .mutableLeaves) as! NSDictionary)
        if body == nil {
            return
        }
        if body!["name"] == nil {
            return
        }
        if chatView == nil {
            return
        }
        var data: NSDictionary?
        if body!["data"] != nil {
            data = (body!["data"] as! NSDictionary)
        } else {
            data = [:]
        }
        let name = body!["name"] as! String
        switch name {
            case ChatController.event_closeSupport:
                onCloseSupport()
                break
            case ChatController.event_clientId:
                let clientId = data!["clientId"] != nil ? data!["clientId"] as! String : ""
                ChatConfig.setClientId(clientId)
                onClientId(clientId)
                break
            case ChatController.event_sendRate:
                onSendRate(data!)
                break
            case ChatController.event_contactsUpdated:
                onContactsUpdated(data!)
                break
            case ChatController.event_clientSendMessage:
                onClientSendMessage(data!)
                break
            case ChatController.event_clientMakeSubscribe:
                onClientMakeSubscribe(data!)
                break
            case ChatController.event_operatorSendMessage:
                onOperatorSendMessage(data!)
                break
            case ChatController.method_getContacts:
                getContactsCallback(data!)
                break
            default:
                break
        }
        onEvent(name, data!)
    }
    
    open func onCloseSupport() {
        if chatView == nil {
            return
        }
        dismiss(animated: true, completion: nil)
        navigationController?.popViewController(animated: true)
    }

    open override func viewDidDisappear(_ animated: Bool) {
        super.viewDidDisappear(animated)

        if animated && chatView != nil {
            chatView.stopLoading()
            callJsDestroy()
            chatView = nil
        }
    }

    open func onLinkPressed(url: URL) {
        UIApplication.shared.openURL(url)
    }
    
    open func playSound(_ systemSoundId: SystemSoundID) {
        AudioServicesPlaySystemSound(systemSoundId)
    }
    
    open func onClientId(_ clientId: String) {
        
    }

    open func onSendRate(_ data: NSDictionary) {
        
    }
    
    open func onContactsUpdated(_ data: NSDictionary) {
        
    }
    
    open func onClientSendMessage(_ data: NSDictionary) {
        
    }
    
    open func onClientMakeSubscribe(_ data: NSDictionary) {
        
    }
    
    open func onOperatorSendMessage(_ data: NSDictionary) {
        playSound(1315)
    }
    
    open func onEvent(_ name: String, _ data: NSDictionary) {
        
    }
    
    open func getContactsCallback(_ data: NSDictionary) {
        
    }
}