//
//  CreateScheduleVM.swift
//  QuickLocation
//
//  Created by 八条 on 2026/6/24.
//

import RxSwift
import RxCocoa
import RxDataSources

// MARK: - 行程点编辑模型
struct SchedulePointItem: IdentifiableType, Equatable {
    let identity: String = UUID().uuidString
    var locationName: String = ""
    var address: String = ""
    var latitude: Double = 0
    var longitude: Double = 0
    var province: String = ""
    var city: String = ""
    var district: String = ""
    var street: String = ""
    var country: String = ""
    var formatted_address: String = ""
    var expectedTime: Date?
    var remark: String = ""
}

typealias SchedulePointSection = SectionModel<String, SchedulePointItem>

class CreateScheduleVM {

    let disposeBag = DisposeBag()

    let scheduModel: ScheduleModel?
    
    // MARK: - Input
    let addPointTapped = PublishSubject<Void>()
    let deletePointAt = PublishSubject<Int>()
    let updatePoint = PublishSubject<(index: Int, item: SchedulePointItem)>()
    let selectedDate = BehaviorRelay<Date>(value: Date())
    var selectedGroupKeys: [String] = []

    /// 切换圈子选中状态（已选则删除，未选则添加）
    func toggleGroupKey(_ key: String) {
        if let idx = selectedGroupKeys.firstIndex(of: key) {
            selectedGroupKeys.remove(at: idx)
        } else {
            selectedGroupKeys.append(key)
        }
    }

    /// 删除指定圈子 key
    func removeGroupKey(_ key: String) {
        selectedGroupKeys.removeAll { $0 == key }
    }

    // MARK: - Output
    let pointsRelay: BehaviorRelay<[SchedulePointItem]>
    let dateString: Observable<String>

    init(_ model: ScheduleModel?) {
        self.scheduModel = model

        // 编辑模式：从 model 回显数据
        if let m = model, !m.points.isEmpty {
            pointsRelay = BehaviorRelay<[SchedulePointItem]>(value: m.points.map { $0.toSchedulePointItem() })
            selectedDate.accept(Date(timeIntervalSince1970: TimeInterval(m.timestamp) / 1000))
            selectedGroupKeys = m.groups.map { $0.group_key }
        } else {
            pointsRelay = BehaviorRelay<[SchedulePointItem]>(value: [SchedulePointItem()])
        }

        dateString = selectedDate
            .map {
                let fmt = DateFormatter()
                fmt.dateFormat = "yyyy年MM月dd日"
                return fmt.string(from: $0)
            }

        // 添加行程点
        addPointTapped
            .withLatestFrom(pointsRelay)
            .map { list in
                var new = list
                new.append(SchedulePointItem())
                return new
            }
            .bind(to: pointsRelay)
            .disposed(by: disposeBag)

        // 删除行程点
        deletePointAt
            .withLatestFrom(pointsRelay) { ($1, $0) }
            .subscribe(onNext: { list, idx in
                guard list.count > 1, idx < list.count else { return }
                var new = list
                new.remove(at: idx)
                self.pointsRelay.accept(new)
            })
            .disposed(by: disposeBag)

        // 更新某个行程点
        updatePoint
            .withLatestFrom(pointsRelay) { ($1, $0) }
            .subscribe(onNext: { list, update in
                guard update.index < list.count else { return }
                var new = list
                new[update.index] = update.item
                self.pointsRelay.accept(new)
            })
            .disposed(by: disposeBag)
    }

}