//
//  OfflineCollectionModels.swift
//  suixinkan
//

import Foundation

/// 线下收款方式，与线上订单支付方式保持独立。
enum OfflineCollectionPaymentMethod: String, Codable, CaseIterable, Sendable, Hashable {
    case wechat = "WECHAT"
    case alipay = "ALIPAY"
    case cash = "CASH"

    /// 页面展示的中文名称。
    var displayName: String {
        switch self {
        case .wechat: "微信"
        case .alipay: "支付宝"
        case .cash: "现金"
        }
    }

    /// 页面使用的本地矢量图标资源名称。
    var assetName: String {
        switch self {
        case .wechat: "payment_method_wechat"
        case .alipay: "payment_method_alipay"
        case .cash: "payment_method_cash"
        }
    }
}

/// 线下收款记录的补缴状态。
enum OfflineCollectionStatus: String, Codable, Sendable, Hashable {
    case pending = "PENDING"
    case settled = "SETTLED"
    case overdue = "OVERDUE"

    /// 状态对应的中文文案。
    var displayName: String {
        switch self {
        case .pending: "待补缴"
        case .settled: "已补缴"
        case .overdue: "逾期未补缴"
        }
    }
}

/// 当前线下收款数据所属的用户、店铺与景区上下文。
struct OfflineCollectionContext: Codable, Sendable, Hashable {
    let collectorId: String
    let collectorName: String
    let storeId: String
    let storeName: String
    let scenicId: String
    let scenicName: String

    /// 生成用于 UserDefaults 隔离不同账号和店铺数据的稳定键。
    var storageScope: String {
        [collectorId, storeId, scenicId]
            .map { value in
                value.unicodeScalars.map { CharacterSet.alphanumerics.contains($0) ? String($0) : "_" }.joined()
            }
            .joined(separator: "_")
    }

    /// 从当前登录上下文解析收款归属，缺少演示数据时使用文档约定的兜底值。
    static func current(appStore: AppStore = .shared) -> OfflineCollectionContext {
        let session = appStore.session
        let stores = appStore.permissions.rolePermissionList().flatMap(\.store)
        let currentStore = stores.first(where: { $0.id == session.currentStoreId }) ?? stores.first
        let collectorName = [session.realName, session.userName, session.accountDisplayName]
            .first { !$0.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty }

        return OfflineCollectionContext(
            collectorId: session.userId.nonEmptyValue ?? "U10086",
            collectorName: collectorName?.trimmingCharacters(in: .whitespacesAndNewlines) ?? "张三",
            storeId: currentStore.map { String($0.id) } ?? (session.currentStoreId > 0 ? String(session.currentStoreId) : "S1001"),
            storeName: currentStore?.name.nonEmptyValue ?? "那拉提旅拍一店",
            scenicId: session.currentScenicId > 0 ? String(session.currentScenicId) : "SC001",
            scenicName: session.currentScenicName.nonEmptyValue ?? "那拉提景区"
        )
    }
}

/// 独立的线下收款记录，不包含任何订单字段。
struct OfflineCollectionRecord: Codable, Sendable, Hashable {
    let id: String
    let collectorId: String
    let collectorName: String
    let storeId: String
    let storeName: String
    let scenicId: String
    let scenicName: String
    let amountFen: Int
    let paymentMethod: OfflineCollectionPaymentMethod
    let registeredAt: Date
    let receivedAt: Date
    let businessDate: String
    var status: OfflineCollectionStatus
    var settlementBatchId: String?
    var settledAt: Date?
}

/// 线下收款的独立补缴流水，仅关联本批次收款记录快照。
struct OfflineSettlementBatch: Codable, Sendable, Hashable {
    let id: String
    let businessDate: String
    let collectorId: String
    let collectorName: String
    let storeId: String
    let storeName: String
    let scenicId: String
    let scenicName: String
    let recordIds: [String]
    let recordCount: Int
    let amountFen: Int
    let paidAt: Date
    let payerId: String
    let payerName: String
    let clientRequestId: String

    /// 流水类型固定为线下收款补缴。
    var transactionType: String { "OFFLINE_COLLECTION_SETTLEMENT" }
}

/// 某一营业日的线下收款汇总。
struct OfflineDailySummary: Sendable, Hashable {
    let businessDate: String
    let totalCount: Int
    let totalAmountFen: Int
    let settledCount: Int
    let settledAmountFen: Int
    let pendingCount: Int
    let pendingAmountFen: Int
    let hasOverdue: Bool

    /// 按记录状态用整数“分”生成日汇总。
    static func make(businessDate: String, records: [OfflineCollectionRecord]) -> OfflineDailySummary {
        let settled = records.filter { $0.status == .settled }
        let pending = records.filter { $0.status == .pending || $0.status == .overdue }
        return OfflineDailySummary(
            businessDate: businessDate,
            totalCount: records.count,
            totalAmountFen: records.reduce(0) { $0 + $1.amountFen },
            settledCount: settled.count,
            settledAmountFen: settled.reduce(0) { $0 + $1.amountFen },
            pendingCount: pending.count,
            pendingAmountFen: pending.reduce(0) { $0 + $1.amountFen },
            hasOverdue: pending.contains { $0.status == .overdue }
        )
    }
}

/// 补缴确认时冻结的记录和金额快照，用于防止处理中新记录被误结清。
struct OfflineSettlementRequest: Sendable, Hashable {
    let businessDate: String
    let recordIds: [String]
    let amountFen: Int
    let clientRequestId: String
}

/// 登记成功后页面反馈所需的最小数据。
struct OfflineCollectionRegistrationReceipt: Sendable, Hashable {
    let record: OfflineCollectionRecord
    let summary: OfflineDailySummary
}

/// 线下收款 Mock 流程可识别的业务异常。
enum OfflineCollectionError: LocalizedError, Sendable, Equatable {
    case invalidAmount
    case createFailed
    case noPendingRecords
    case summaryMismatch
    case recordsChanged
    case settlementFailed
    case persistenceFailed

    /// 供页面展示的中文错误提示。
    var errorDescription: String? {
        switch self {
        case .invalidAmount: "请输入0.01～99,999.99元的有效金额"
        case .createFailed: "登记失败，请重试"
        case .noPendingRecords: "当前营业日无待补缴记录"
        case .summaryMismatch: "金额汇总异常，请刷新数据"
        case .recordsChanged: "待补缴记录已变化，请重新确认"
        case .settlementFailed: "补缴失败，请重试"
        case .persistenceFailed: "本地数据保存失败，请重试"
        }
    }
}

/// 金额输入、整数分换算和展示的统一工具。
enum OfflineCollectionMoney {
    static let maximumFen = 9_999_999

    /// 判断文本是否可作为金额输入中间态。
    static func acceptsEditingText(_ text: String) -> Bool {
        guard !text.contains(where: { !$0.isNumber && $0 != "." }) else { return false }
        let parts = text.split(separator: ".", omittingEmptySubsequences: false)
        guard parts.count <= 2 else { return false }
        let wholeCount = parts.first?.count ?? 0
        let fractionCount = parts.count == 2 ? parts[1].count : 0
        return wholeCount <= 5 && fractionCount <= 2
    }

    /// 将用户输入精确转换为整数“分”，不经过浮点计算。
    static func parseFen(_ rawValue: String) -> Int? {
        let text = rawValue.trimmingCharacters(in: .whitespacesAndNewlines)
        guard !text.isEmpty, text == rawValue, acceptsEditingText(text), text != "." else { return nil }

        let parts = text.split(separator: ".", omittingEmptySubsequences: false)
        let wholeText = parts[0].isEmpty ? "0" : String(parts[0])
        let fractionText = parts.count == 2 ? String(parts[1]) : ""
        guard wholeText.allSatisfy(\.isNumber), fractionText.allSatisfy(\.isNumber),
              let whole = Int(wholeText) else { return nil }

        let cents: Int
        switch fractionText.count {
        case 0: cents = 0
        case 1: cents = (Int(fractionText) ?? 0) * 10
        case 2: cents = Int(fractionText) ?? 0
        default: return nil
        }
        let amountFen = whole * 100 + cents
        guard amountFen > 0, amountFen <= maximumFen else { return nil }
        return amountFen
    }

    /// 将整数分格式化为带人民币符号且固定两位小数的文本。
    static func display(_ amountFen: Int) -> String {
        let sign = amountFen < 0 ? "-" : ""
        let absolute = abs(amountFen)
        return "\(sign)¥\(absolute / 100).\(String(format: "%02d", absolute % 100))"
    }
}

/// 营业日与页面时间文案的统一格式化工具。
enum OfflineCollectionDate {
    static let dailyCutoffTime = "23:59:59"

    /// 按指定日历生成 YYYY-MM-DD 营业日。
    static func businessDate(for date: Date, calendar: Calendar = .current) -> String {
        let components = calendar.dateComponents([.year, .month, .day], from: date)
        return String(
            format: "%04d-%02d-%02d",
            components.year ?? 0,
            components.month ?? 0,
            components.day ?? 0
        )
    }

    /// 将营业日文本解析为当地日期。
    static func date(from businessDate: String, calendar: Calendar = .current) -> Date? {
        let formatter = DateFormatter()
        formatter.calendar = calendar
        formatter.locale = Locale(identifier: "en_US_POSIX")
        formatter.timeZone = calendar.timeZone
        formatter.dateFormat = "yyyy-MM-dd"
        return formatter.date(from: businessDate)
    }

    /// 将时间格式化为当日明细所需的 HH:mm。
    static func timeText(_ date: Date, calendar: Calendar = .current) -> String {
        let formatter = DateFormatter()
        formatter.calendar = calendar
        formatter.locale = Locale(identifier: "zh_CN")
        formatter.timeZone = calendar.timeZone
        formatter.dateFormat = "HH:mm"
        return formatter.string(from: date)
    }

    /// 将时间格式化为补缴流水的完整时间。
    static func dateTimeText(_ date: Date, calendar: Calendar = .current) -> String {
        let formatter = DateFormatter()
        formatter.calendar = calendar
        formatter.locale = Locale(identifier: "zh_CN")
        formatter.timeZone = calendar.timeZone
        formatter.dateFormat = "yyyy-MM-dd HH:mm"
        return formatter.string(from: date)
    }
}

private extension String {
    /// 去除首尾空白后的非空文本。
    var nonEmptyValue: String? {
        let value = trimmingCharacters(in: .whitespacesAndNewlines)
        return value.isEmpty ? nil : value
    }
}