//
//  DatabaseHelper.swift
//  MTP2_iOS
//
//  Created by zhongyuan on 2018/6/9.
//  Copyright © 2018年 zhongyuan.All rights reserved.
//

import UIKit
import CoreData

enum DataBaseError: Error {
    case NoFindUser
    case NoFindSelfGoods
}

/// Database Helper
class DatabaseHelper {
    static let appDelegate = UIApplication.shared.delegate as! AppDelegate
    
    // MARK: - 生命周期相关
    static func firstOpenInitialData() {
        // 判断是否第一次运行
        if !UserDefaultsUtils.isFirstOpen() { return }
        
        // 初始化可能与登录相关的错误码
        var errorCodeInfos = [MoErrorCodeInfo]()
        errorCodeInfos.append(MoErrorCodeInfo(errorCode: "1003", errorMsg: "账号或密码不匹配"))
        errorCodeInfos.append(MoErrorCodeInfo(errorCode: "1004", errorMsg: "无效账号"))
        errorCodeInfos.append(MoErrorCodeInfo(errorCode: "1005", errorMsg: "账号类型不匹配"))
        errorCodeInfos.append(MoErrorCodeInfo(errorCode: "1006", errorMsg: "账号不在线"))
        errorCodeInfos.append(MoErrorCodeInfo(errorCode: "1007", errorMsg: "操作权限不够"))
        errorCodeInfos.append(MoErrorCodeInfo(errorCode: "1008", errorMsg: "会员无账户在线"))
        errorCodeInfos.append(MoErrorCodeInfo(errorCode: "1009", errorMsg: "账户在别处登录"))
        errorCodeInfos.append(MoErrorCodeInfo(errorCode: "1010", errorMsg: "值为空"))
        errorCodeInfos.append(MoErrorCodeInfo(errorCode: "1011", errorMsg: "登录账户已经存在"))
        errorCodeInfos.append(MoErrorCodeInfo(errorCode: "1012", errorMsg: "软件版本过低不能登录"))
        errorCodeInfos.append(MoErrorCodeInfo(errorCode: "1013", errorMsg: "IP地址不在允许范围内"))
        
        try? updateErrorCodeInfos(errorCodeInfos: errorCodeInfos)
    }
    
    // MARK: - 账户相关
    /// 获取指定用户id的本地用户信息对象
    ///
    /// - Parameter userID: 用户id
    /// - Returns: 用户信息对象
    static func getUser(userID: UInt32) throws -> UserEntity? {
        let fetchRequest: NSFetchRequest<UserEntity> = UserEntity.fetchRequest()
        fetchRequest.predicate = NSPredicate(format: "userID == %ld", userID)
        
        let result = try appDelegate.mainManagedObjectContext.fetch(fetchRequest)
        
        return result.count != 0 ? result[0] : nil
    }
    
    static func getUser(userID: UInt32, type: Int16) throws -> UserEntity? {
        let fetchRequest: NSFetchRequest<UserEntity> = UserEntity.fetchRequest()
        fetchRequest.predicate = NSPredicate(format: "userID == %ld and type == %ld", userID,type)
        
        let result = try appDelegate.mainManagedObjectContext.fetch(fetchRequest)
        
        return result.count != 0 ? result[0] : nil
    }
    
    /// 获取所有保存的用户信息
    ///
    /// - Parameter type: 类型，0为实盘（默认值）；1为模拟盘
    /// - Returns: 用户信息数组
    /// - Throws: 数据库操作错误
    static func getUsers(type: Int16 = 0) throws -> [UserEntity]? {
        let fetchRequest: NSFetchRequest<UserEntity> = UserEntity.fetchRequest()
        fetchRequest.predicate = NSPredicate(format: "type == %ld", type)
        fetchRequest.sortDescriptors = [NSSortDescriptor(key: "loginDate", ascending: false)]
        
        let result = try appDelegate.mainManagedObjectContext.fetch(fetchRequest)
        return result.count != 0 ? result : nil
    }
    
    /// - Parameters:
    ///   - userID: 用户id
    ///   - loginID: 登录id
    ///   - type: 类型，0为实盘（默认值）；1为模拟盘
    /// - Throws: 数据库操作错误
    static func addUser(userID: UInt32, loginID: String, loginDate: Date, type: Int16 = 0) throws {
        if let userEntity = try getUser(userID: userID, type: type) {
            userEntity.loginDate = loginDate
        } else {
            guard let userEntity = NSEntityDescription.insertNewObject(forEntityName: "UserEntity", into: appDelegate.backGroundObjectContext) as? UserEntity else { return }
            
            userEntity.userID = Int64(Int32(userID))
            userEntity.loginID = loginID
            userEntity.loginDate = loginDate
            userEntity.type = type
        }
        
        appDelegate.backGroundObjectContext.perform {
            if appDelegate.backGroundObjectContext.hasChanges {
                try? appDelegate.backGroundObjectContext.save()
            }
        }
    }
    
    static func deleteUser(userID: UInt32) throws {
        do {
            if let userEntity = try getUser(userID: userID) {
                appDelegate.backGroundObjectContext.perform {
                    appDelegate.backGroundObjectContext.delete(appDelegate.backGroundObjectContext.object(with: userEntity.objectID))
                    if appDelegate.backGroundObjectContext.hasChanges {
                        try? appDelegate.backGroundObjectContext.save()
                    }
                }
            }
        } catch {
            throw DataBaseError.NoFindUser
        }
    }
    
    // MARK: - 错误码相关
    static func updateErrorCodeInfos(errorCodeInfos: [MoErrorCodeInfo]) throws {
        
        func deleteAllErrorCodeInfos() throws {
            let fetchRequest = NSFetchRequest<NSFetchRequestResult>(entityName: "ErrorEntity")
            let batchDeleteRequest = NSBatchDeleteRequest(fetchRequest: fetchRequest)
            try appDelegate.backGroundObjectContext.execute(batchDeleteRequest)
        }
        
        if errorCodeInfos.count <= 0 { return }
        
        // 批量删除原有数据
        try deleteAllErrorCodeInfos()
        
        appDelegate.backGroundObjectContext.perform {
            for moErrorCodeInfo in errorCodeInfos {
                // FIXME: 可能会报 EXC_BAD_ACCESS
                guard let errorEntity = NSEntityDescription.insertNewObject(forEntityName: "ErrorEntity", into: appDelegate.backGroundObjectContext) as? ErrorEntity else { return }
                errorEntity.constkey = moErrorCodeInfo.errorCode
                errorEntity.remarks = moErrorCodeInfo.errorMsg
            }
            if appDelegate.backGroundObjectContext.hasChanges {
                try? appDelegate.backGroundObjectContext.save()
            }
        }
    }
    
    static func getError(errorCode: String) throws -> ErrorEntity? {
        let fetchRequest: NSFetchRequest<ErrorEntity> = ErrorEntity.fetchRequest()
        fetchRequest.predicate = NSPredicate(format: "constkey == %@", errorCode)
        
        let result = try appDelegate.mainManagedObjectContext.fetch(fetchRequest)
        
        return result.count != 0 ? result[0] : nil
    }
    
    // MARK: - 自选商品相关
    static func getSelfQuotes(userID: UInt32) throws -> [SelfEntity] {
        if let userEntity = try getUser(userID: userID) {
            if let selfGoods = userEntity.selfGoods?.allObjects as? [SelfEntity] {
                return selfGoods
            }
        }
        
        return []
    }
    
    static func addSelfGoods(userID: UInt32, goodsID: Int64, marketID: Int64) throws {
        if let userEntity = try getUser(userID: userID) {
            guard let selfEntity = NSEntityDescription.insertNewObject(forEntityName: "SelfEntity", into: appDelegate.backGroundObjectContext) as? SelfEntity else { return }
            
            appDelegate.backGroundObjectContext.perform {
                selfEntity.goodsID = goodsID
                selfEntity.marketID = marketID
                selfEntity.createTime = NSDate()
                let userEntity: UserEntity = appDelegate.backGroundObjectContext.object(with: userEntity.objectID) as! UserEntity
                userEntity.addToSelfGoods(selfEntity)
                if appDelegate.backGroundObjectContext.hasChanges {
                    do {
                        try appDelegate.backGroundObjectContext.save()
                    } catch {
                        dPrint(error.localizedDescription)
                    }
                }
            }
        } else {
            throw DataBaseError.NoFindUser
        }
    }
    
    static func removeSelfGoods(userID: UInt32, goodsID: Int64) throws {
        if let userEntity = try getUser(userID: userID) {
            if case let selfEntity as SelfEntity = userEntity.selfGoods?.first(where: { ($0 as! SelfEntity).goodsID == goodsID }) {
                appDelegate.backGroundObjectContext.perform {
                    userEntity.removeFromSelfGoods(selfEntity)
                    appDelegate.backGroundObjectContext.delete(appDelegate.backGroundObjectContext.object(with: selfEntity.objectID))  // 这一句记得要调用
                    
                    if appDelegate.backGroundObjectContext.hasChanges {
                        try? appDelegate.backGroundObjectContext.save()
                    }
                }
            } else {
                throw DataBaseError.NoFindSelfGoods
            }
        } else {
            throw DataBaseError.NoFindUser
        }
    }
    
    //MARK: - 商品相关
    static func insertGoodsInfos(_ goodsInfos: [MoGoodsInfo]) throws {
        /// 先移出商品
        do {
            for goods in goodsInfos {
                let exist = try? self.getGoodsInfo(ById: goods.goodsid)
                if exist ?? false { self.removeGoodsInfo(goods.goodsid) }
            }
        }
        
        appDelegate.backGroundObjectContext.performAndWait {
            do {
                dPrint("1.当前时间：\(Date().getString())")
                for goodsInfo in goodsInfos {
                    guard let goodsInfoEntity = NSEntityDescription.insertNewObject(forEntityName: "GoodsInfoEntity", into: appDelegate.backGroundObjectContext) as? GoodsInfoEntity else { continue
                    }
                    goodsInfoEntity.setupWith(goodsInfo: goodsInfo)
                }
                dPrint("2.当前时间：\(Date().getString())")
                if appDelegate.backGroundObjectContext.hasChanges {
                    dPrint("3.当前时间：\(Date().getString())")
                    try appDelegate.backGroundObjectContext.save()
                    dPrint("4.当前时间：\(Date().getString())")
                } else {
                    dPrint("商品本地化失败")
                }
            } catch {
                fatalError("商品数据插入失败")
            }
        }
    }
    
    /// 判断指定商品信息是否存在
    ///
    /// - Parameter Id: 商品ID
    /// - Returns: yes: 存在 no: 不存在
    /// - Throws:
    static func getGoodsInfo(ById Id: Int) throws -> Bool {
        let fetchRequest: NSFetchRequest<GoodsInfoEntity> = GoodsInfoEntity.fetchRequest()
        fetchRequest.predicate = NSPredicate(format: "goodsId == %ld", Int32(Id))
        
        let count = try appDelegate.mainManagedObjectContext.count(for: fetchRequest)
        return count > 0
    }
    
    /// 获取所有商品信息
    ///
    /// - Returns: 所有保存的商品信息
    /// - Throws:
    static func getGoodsInfo() throws -> [MoGoodsInfo] {
        
        let fetchRequest: NSFetchRequest<GoodsInfoEntity> = GoodsInfoEntity.fetchRequest()
        
        fetchRequest.sortDescriptors = [NSSortDescriptor(key: "goodsCode", ascending: true)]
        
        let goodsInfos = try appDelegate.mainManagedObjectContext.fetch(fetchRequest)
        
        let moGoodsInfos = goodsInfos.compactMap({ $0.toMoGoodsInfo() })
        return moGoodsInfos
    }
    
    /// 判断本地数据库是否有数据
    ///
    /// - Returns: yes: 存在 no: 不存在
    /// - Throws:
    static func goodsInfoIsExist() -> Bool {
        let fetchRequest: NSFetchRequest<GoodsInfoEntity> = GoodsInfoEntity.fetchRequest()
        do {
            let count = try appDelegate.mainManagedObjectContext.count(for: fetchRequest)
            return count > 0
        } catch {
            fatalError()
        }
    }
    
    /// 根据查询条件获取符合条件的商品
    ///
    /// - Parameter searchCondition: 查询条件
    /// - Returns: 符合条件的商品
    /// - Throws:
    static func getGoodsInfo(ByCondition searchCondition: String) throws -> [MoGoodsInfo] {
    
        guard !searchCondition.isEmpty else { return [] }
        
        let fetchRequest: NSFetchRequest<GoodsInfoEntity> = GoodsInfoEntity.fetchRequest()
        if RegularUtils.checkNumber(with: searchCondition) {
            let regularString = ".*\(searchCondition).*"
            fetchRequest.predicate = NSPredicate(format: "searchCondition MATCHES %@", regularString)
        } else {
            var regularString = ".*"
            for s in searchCondition.uppercased() {
                regularString.append(s)
                regularString.append(".*")
            }
            fetchRequest.predicate = NSPredicate(format: "searchCondition MATCHES %@", regularString)
        }
        
        fetchRequest.sortDescriptors = [NSSortDescriptor(key: "goodsCode", ascending: true)]
        
        let goodsInfos = try appDelegate.mainManagedObjectContext.fetch(fetchRequest)
        let moGoodsInfos = goodsInfos.compactMap({ $0.toMoGoodsInfo() })
        
        return moGoodsInfos
    }
    
    /// 删除所有的商品数据信息
    static func removeAllGoodsInfo() {
        /// 获取上下文对象
        let viewContext = appDelegate.persistentContainer.viewContext
        /// 获取实例
        let entity = NSFetchRequest<NSFetchRequestResult>(entityName: "GoodsInfoEntity")
        let deleteRequest = NSBatchDeleteRequest(fetchRequest: entity)
        let _ = try? viewContext.persistentStoreCoordinator?.execute(deleteRequest, with: viewContext)
        
        appDelegate.backGroundObjectContext.perform {
            if appDelegate.backGroundObjectContext.hasChanges {
                do {
                    _ = try? viewContext.persistentStoreCoordinator?.execute(deleteRequest, with: viewContext)
                }
            }
        }
    }
    
    /// 删除所有的商品数据信息
    static func removeGoodsInfo(_ goodsid: Int) {
        /// 获取上下文对象
        let viewContext = appDelegate.persistentContainer.viewContext
        /// 获取实例
        let fetchRequest = NSFetchRequest<NSFetchRequestResult>(entityName: "GoodsInfoEntity")
        fetchRequest.predicate = NSPredicate(format: "goodsId == %ld", Int64(goodsid))
        let deleteRequest = NSBatchDeleteRequest(fetchRequest: fetchRequest)
        let _ = try? viewContext.persistentStoreCoordinator?.execute(deleteRequest, with: viewContext)
        
        appDelegate.backGroundObjectContext.perform {
            if appDelegate.backGroundObjectContext.hasChanges {
                do {
                    _ = try? viewContext.persistentStoreCoordinator?.execute(deleteRequest, with: viewContext)
                }
            }
        }
    }
    
    /// 根据goodsid获取对应的商品数据
    /// - Parameter goodsid: goodsid
    static func getMoGoodsInfo(where goodsids: [Int]) throws -> [MoGoodsInfo]? {
        /// 获取商品数据
        var goodsInfo: [MoGoodsInfo] = []
        let fetchRequest: NSFetchRequest<GoodsInfoEntity> = GoodsInfoEntity.fetchRequest()
        for goodsid in goodsids {
            fetchRequest.predicate = NSPredicate(format: "goodsId == %ld", Int64(goodsid))
            let goodsInfos = try appDelegate.mainManagedObjectContext.fetch(fetchRequest)
            if goodsInfos.count != 0 { goodsInfo.append(goodsInfos[0].toMoGoodsInfo()) }
        }
        return goodsInfo
    }
    
}