//
//  GroupItineraryView.swift
//  QuickLocation
//

import UIKit
import RxSwift
import RxCocoa
import SwiftDate

/// 圈子 Tab 下的「行程」内容页
final class GroupItineraryView: UIView {

    var disposeBag = DisposeBag()

    var onSwitchGroup: (() -> Void)?
    var onDeleteSchedule: ((ScheduleModel) -> Void)?
    var onSelectSchedule: ((ScheduleModel) -> Void)?

    func updateGroupName(_ name: String) {
        groupNameLab.text = name.isEmpty ? " " : name
    }

    func reloadSchedules(_ list: [ScheduleModel]) {
        scheduleSections = Self.groupByDay(list)
        tableView.reloadData()
        tableView.refresh(status: .noMoreData, isEmpty: list.isEmpty)
    }

    private var scheduleSections: [(dayText: String, dateText: String, items: [ScheduleModel])] = []

    private func setupUI() {
        addSubview(headerRow)
        headerRow.addSubview(groupIcon)
        headerRow.addSubview(groupNameLab)
        headerRow.addSubview(changeGroupBtn)
        addSubview(tableView)
        addSubview(createBtn)
        
        headerRow.layoutChain
            .top(8)
            .edgesHorzontal(16)
            .height(28)

        groupIcon.layoutChain
            .left()
            .centerY()
            .width(22)
            .height(22)

        changeGroupBtn.layoutChain
            .right()
            .centerY()
            .height(28)

        groupNameLab.layoutChain
            .leftToRightOfView(groupIcon, offset: 8)
            .centerY()
            .rightToLeftOfView(changeGroupBtn, offset: -8, relation: .lessThanOrEqual)

        tableView.layoutChain
            .topToBottomOfView(headerRow, offset: 12)
            .edgesHorzontal()
            .bottom()
        
        createBtn.layoutChain
            .bottom(kSafeBottomMargin + 102)
            .right(20)
            .width(54)
            .heightToWidth(1)
    }

    private func setupRx() {
        createBtn.rx.tap.subscribe(onNext: { _ in
            AppRouter.push(Route.createSchedule)
        }).disposed(by: disposeBag)
        
        changeGroupBtn.rx.tap
            .subscribe(onNext: { [weak self] in self?.onSwitchGroup?() })
            .disposed(by: disposeBag)
    }

    private static func groupByDay(_ list: [ScheduleModel]) -> [(dayText: String, dateText: String, items: [ScheduleModel])] {
        let sorted = list.sorted { $0.timestamp > $1.timestamp }
        var map: [String: [ScheduleModel]] = [:]
        var order: [String] = []
        var dayDateMap: [String: (dayText: String, dateText: String)] = [:]
        let fmt = DateFormatter()
        fmt.locale = Locale(identifier: "zh_CN")
        let calendar = Calendar.current
        for item in sorted {
            let date = Date(timeIntervalSince1970: TimeInterval(item.timestamp) / 1000)
            fmt.dateFormat = "M月d日"
            let dateText = fmt.string(from: date)
            let dayText: String
            if calendar.isDateInToday(date) {
                dayText = "今天"
            } else if calendar.isDateInYesterday(date) {
                dayText = "昨天"
            } else {
                fmt.dateFormat = "EEEE"
                dayText = fmt.string(from: date)
            }
            let key = "\(dayText) \(dateText)"
            if map[key] == nil {
                order.append(key)
                dayDateMap[key] = (dayText, dateText)
                map[key] = []
            }
            map[key]?.append(item)
        }
        return order.map { key in
            let pair = dayDateMap[key] ?? ("", "")
            return (pair.dayText, pair.dateText, map[key] ?? [])
        }
    }

    lazy var headerRow: UIView = {
        let v = UIView()
        v.backgroundColor = .clear
        return v
    }()

    lazy var groupIcon: UIImageView = {
        let iv = UIImageView(image: UIImage(named: "Home/group_name_icon"))
        iv.contentMode = .scaleAspectFit
        return iv
    }()

    lazy var groupNameLab: UILabel = {
        let label = UILabel()
        label.font = .systemFont(ofSize: 16, weight: .bold)
        label.textColor = UIColor(hexStr: "#353B4F")
        label.text = " "
        return label
    }()

    lazy var changeGroupBtn: UIButton = {
        let btn = UIButton(type: .custom)
        btn.setTitle("切换圈子 ", for: .normal)
        btn.setTitleColor(UIColor(hexStr: "#353B4F"), for: .normal)
        btn.titleLabel?.font = .systemFont(ofSize: 12, weight: .medium)
        btn.setImage(UIImage(named: "Common/arrow_right"), for: .normal)
        btn.semanticContentAttribute = .forceRightToLeft
        return btn
    }()

    lazy var tableView: UITableView = {
        let tv = UITableView(frame: .zero, style: .grouped)
        tv.backgroundColor = UIColor(hexStr: "#FAFAFA")
        tv.separatorStyle = .none
        tv.showsVerticalScrollIndicator = false
        tv.register(GroupItineraryCell.self)
        tv.dataSource = self
        tv.delegate = self
        tv.estimatedRowHeight = 100
        tv.rowHeight = UITableView.automaticDimension
        tv.sectionHeaderHeight = 36
        tv.contentInset = UIEdgeInsets(top: 0, left: 0, bottom: 97 + kSafeBottomMargin, right: 0)
        if #available(iOS 15.0, *) {
            tv.sectionHeaderTopPadding = 0
        }
        tv.dl.addEmptyDataSet { emptyDataSet in
            emptyDataSet.emptyNoDataTitle = "这里怎么什么都没有~"
            emptyDataSet.emptyNoDataDetail = ""
            emptyDataSet.customButtonTitle = ""
            emptyDataSet.backgroundColor = .clear
            emptyDataSet.offsetY = -100
        }
        return tv
    }()
    
    lazy var createBtn: UIButton = {
        let btn = UIButton()
        btn.setImage(UIImage(named: "Schedule/create"), for: .normal)
        return btn
    }()

    override init(frame: CGRect) {
        super.init(frame: frame)
        backgroundColor = .clear
        setupUI()
        setupRx()
    }

    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
}

// MARK: - UITableView
extension GroupItineraryView: UITableViewDataSource, UITableViewDelegate {
    func numberOfSections(in tableView: UITableView) -> Int {
        scheduleSections.count
    }

    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        scheduleSections[section].items.count
    }

    func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
        let header = UIView()
        header.backgroundColor = .clear
        let sectionData = scheduleSections[section]
        let label = UILabel()
        let color = UIColor(hexStr: "#353B4F")
        let attr = NSMutableAttributedString()
        attr.append(NSAttributedString(
            string: sectionData.dayText,
            attributes: [
                .font: UIFont.systemFont(ofSize: 16, weight: .bold),
                .foregroundColor: color
            ]
        ))
        if !sectionData.dateText.isEmpty {
            attr.append(NSAttributedString(
                string: " \(sectionData.dateText)",
                attributes: [
                    .font: UIFont.systemFont(ofSize: 13, weight: .medium),
                    .foregroundColor: color
                ]
            ))
        }
        label.attributedText = attr
        header.addSubview(label)
        label.layoutChain.left(16).centerY()
        return header
    }

    func tableView(_ tableView: UITableView, heightForFooterInSection section: Int) -> CGFloat {
        .leastNormalMagnitude
    }

    func tableView(_ tableView: UITableView, viewForFooterInSection section: Int) -> UIView? {
        UIView()
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell: GroupItineraryCell = tableView.dequeueReusableCell(for: indexPath)
        cell.configure(scheduleSections[indexPath.section].items[indexPath.row])
        return cell
    }

    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        onSelectSchedule?(scheduleSections[indexPath.section].items[indexPath.row])
    }

}

// MARK: - GroupItineraryCell
final class GroupItineraryCell: UITableViewCell {

    func configure(_ model: ScheduleModel) {
        avatarImg.image = model.userIcon
        nameLab.text = model.nick_name.isEmpty ? "未命名用户" : model.nick_name
        followIcon.isHidden = !model.is_follow

        let points = Self.orderedPoints(model.points)
        startLocationLab.text = Self.locationName(points.first)
        endLocationLab.text = Self.locationName(points.last, maximumCharacters: 4)
        durationLab.text = Self.durationText(from: points.first, to: points.last)
        configureTags(model.groups.map(\.group_name).filter { !$0.isEmpty })
    }

    override init(style: CellStyle, reuseIdentifier: String?) {
        super.init(style: style, reuseIdentifier: reuseIdentifier)
        selectionStyle = .none
        backgroundColor = .clear
        contentView.backgroundColor = .clear

        contentView.addSubview(cardView)
        cardView.addSubview(avatarImg)
        cardView.addSubview(nameLab)
        cardView.addSubview(followIcon)
        cardView.addSubview(startMarkerLab)
        cardView.addSubview(startLocationLab)
        cardView.addSubview(routeLineView)
        cardView.addSubview(durationLab)
        cardView.addSubview(endMarkerLab)
        cardView.addSubview(endLocationLab)
        cardView.addSubview(tagScrollView)
        tagScrollView.addSubview(tagStackView)

        cardView.layoutChain
            .edgesVertical(6)
            .edgesHorzontal(15)

        avatarImg.layoutChain
            .top(12)
            .left(14)
            .width(28)
            .height(28)

        nameLab.layoutChain
            .leftToRightOfView(avatarImg, offset: 8)
            .centerY(avatarImg)

        followIcon.layoutChain
            .leftToRightOfView(nameLab, offset: 7)
            .centerY(nameLab)
            .width(20)
            .height(20)

        followIcon.translatesAutoresizingMaskIntoConstraints = false
        followIcon.trailingAnchor.constraint(lessThanOrEqualTo: cardView.trailingAnchor, constant: -14).isActive = true

        startMarkerLab.translatesAutoresizingMaskIntoConstraints = false
        startLocationLab.translatesAutoresizingMaskIntoConstraints = false
        routeLineView.translatesAutoresizingMaskIntoConstraints = false
        durationLab.translatesAutoresizingMaskIntoConstraints = false
        endMarkerLab.translatesAutoresizingMaskIntoConstraints = false
        endLocationLab.translatesAutoresizingMaskIntoConstraints = false
        tagScrollView.translatesAutoresizingMaskIntoConstraints = false
        tagStackView.translatesAutoresizingMaskIntoConstraints = false

        NSLayoutConstraint.activate([
            startMarkerLab.leadingAnchor.constraint(equalTo: cardView.leadingAnchor, constant: 14),
            startMarkerLab.topAnchor.constraint(equalTo: avatarImg.bottomAnchor, constant: 10),
            startMarkerLab.widthAnchor.constraint(equalToConstant: 20),
            startMarkerLab.heightAnchor.constraint(equalToConstant: 20),

            startLocationLab.leadingAnchor.constraint(equalTo: startMarkerLab.trailingAnchor, constant: 7),
            startLocationLab.centerYAnchor.constraint(equalTo: startMarkerLab.centerYAnchor),
            startLocationLab.widthAnchor.constraint(lessThanOrEqualToConstant: 82),

            endLocationLab.trailingAnchor.constraint(equalTo: cardView.trailingAnchor, constant: -14),
            endLocationLab.centerYAnchor.constraint(equalTo: startMarkerLab.centerYAnchor),
            endLocationLab.widthAnchor.constraint(lessThanOrEqualToConstant: 82),

            endMarkerLab.trailingAnchor.constraint(equalTo: endLocationLab.leadingAnchor, constant: -7),
            endMarkerLab.centerYAnchor.constraint(equalTo: startMarkerLab.centerYAnchor),
            endMarkerLab.widthAnchor.constraint(equalToConstant: 20),
            endMarkerLab.heightAnchor.constraint(equalToConstant: 20),

            routeLineView.leadingAnchor.constraint(equalTo: startLocationLab.trailingAnchor, constant: 8),
            routeLineView.trailingAnchor.constraint(equalTo: endMarkerLab.leadingAnchor, constant: -8),
            routeLineView.centerYAnchor.constraint(equalTo: startMarkerLab.centerYAnchor, constant: 4),
            routeLineView.heightAnchor.constraint(equalToConstant: 1),
            routeLineView.widthAnchor.constraint(greaterThanOrEqualToConstant: 28),

            durationLab.centerXAnchor.constraint(equalTo: routeLineView.centerXAnchor),
            durationLab.bottomAnchor.constraint(equalTo: routeLineView.topAnchor, constant: -3),
            durationLab.widthAnchor.constraint(lessThanOrEqualTo: routeLineView.widthAnchor, constant: 24),

            tagScrollView.topAnchor.constraint(equalTo: startMarkerLab.bottomAnchor, constant: 8),
            tagScrollView.leadingAnchor.constraint(equalTo: cardView.leadingAnchor, constant: 90),
            tagScrollView.trailingAnchor.constraint(equalTo: cardView.trailingAnchor, constant: -14),
            tagScrollView.heightAnchor.constraint(equalToConstant: 18),
            tagScrollView.bottomAnchor.constraint(equalTo: cardView.bottomAnchor, constant: -10),

            tagStackView.leadingAnchor.constraint(equalTo: tagScrollView.contentLayoutGuide.leadingAnchor),
            tagStackView.trailingAnchor.constraint(equalTo: tagScrollView.contentLayoutGuide.trailingAnchor),
            tagStackView.topAnchor.constraint(equalTo: tagScrollView.contentLayoutGuide.topAnchor),
            tagStackView.bottomAnchor.constraint(equalTo: tagScrollView.contentLayoutGuide.bottomAnchor),
            tagStackView.heightAnchor.constraint(equalTo: tagScrollView.frameLayoutGuide.heightAnchor),
            tagStackView.widthAnchor.constraint(greaterThanOrEqualTo: tagScrollView.frameLayoutGuide.widthAnchor)
        ])
    }

    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    private lazy var cardView: UIView = {
        let v = UIView()
        v.backgroundColor = .white
        v.cornerRadius = 16
        return v
    }()

    private lazy var avatarImg: UIImageView = {
        let iv = UIImageView()
        iv.contentMode = .scaleAspectFill
        iv.cornerRadius = 10
        iv.clipsToBounds = true
        return iv
    }()

    private lazy var nameLab: UILabel = {
        let label = UILabel()
        label.font = .systemFont(ofSize: 15, weight: .bold)
        label.textColor = UIColor(hexStr: "#353B4F")
        label.setContentCompressionResistancePriority(.defaultLow, for: .horizontal)
        return label
    }()

    private lazy var followIcon: UIImageView = {
        let view = UIImageView(image: Self.followBadgeImage())
        view.contentMode = .scaleAspectFit
        return view
    }()

    private static func followBadgeImage() -> UIImage? {
        let size = CGSize(width: 22, height: 18)
        UIGraphicsBeginImageContextWithOptions(size, false, 0)
        defer { UIGraphicsEndImageContext() }
        let configuration = UIImage.SymbolConfiguration(pointSize: 13, weight: .bold)
        UIImage(systemName: "heart.fill", withConfiguration: configuration)?
            .withTintColor(UIColor(hexStr: "#FF9AC1"), renderingMode: .alwaysOriginal)
            .draw(in: CGRect(x: 0, y: 1, width: 15, height: 15))
        UIImage(systemName: "heart.fill", withConfiguration: configuration)?
            .withTintColor(UIColor(hexStr: "#FF78AC"), renderingMode: .alwaysOriginal)
            .draw(in: CGRect(x: 8, y: 3, width: 14, height: 14))
        return UIGraphicsGetImageFromCurrentImageContext()
    }

    private lazy var startMarkerLab: UILabel = makeMarkerLabel(text: "始")
    private lazy var endMarkerLab: UILabel = makeMarkerLabel(text: "终")

    private func makeMarkerLabel(text: String) -> UILabel {
        let label = UILabel()
        label.text = text
        label.font = FontManager.youSheBiaoTiHei(11)
        label.textColor = UIColor(hexStr: "#58EDFF")
        label.textAlignment = .center
        label.backgroundColor = UIColor(hexStr: "#293445")
        label.cornerRadius = 7
        label.clipsToBounds = true
        return label
    }

    private lazy var startLocationLab: UILabel = makeLocationLabel()
    private lazy var endLocationLab: UILabel = makeLocationLabel()

    private func makeLocationLabel() -> UILabel {
        let label = UILabel()
        label.font = .systemFont(ofSize: 14, weight: .medium)
        label.textColor = UIColor(hexStr: "#353B4F")
        label.lineBreakMode = .byTruncatingTail
        label.setContentCompressionResistancePriority(.defaultLow, for: .horizontal)
        return label
    }

    private lazy var durationLab: UILabel = {
        let label = UILabel()
        label.font = .systemFont(ofSize: 12, weight: .regular)
        label.textColor = UIColor(hexStr: "#888888")
        label.textAlignment = .center
        label.backgroundColor = .white
        label.lineBreakMode = .byTruncatingTail
        return label
    }()

    private lazy var routeLineView: GroupItineraryDashLineView = {
        GroupItineraryDashLineView()
    }()

    private lazy var tagScrollView: UIScrollView = {
        let view = UIScrollView()
        view.showsHorizontalScrollIndicator = false
        view.alwaysBounceHorizontal = false
        return view
    }()

    private lazy var tagStackView: UIStackView = {
        let view = UIStackView()
        view.axis = .horizontal
        view.alignment = .fill
        view.spacing = 6
        view.addArrangedSubview(tagSpacerView)
        return view
    }()

    private lazy var tagSpacerView: UIView = {
        let view = UIView()
        view.setContentHuggingPriority(.defaultLow, for: .horizontal)
        view.setContentCompressionResistancePriority(.defaultLow, for: .horizontal)
        return view
    }()

    private func configureTags(_ names: [String]) {
        tagStackView.arrangedSubviews.filter { $0 !== tagSpacerView }.forEach {
            tagStackView.removeArrangedSubview($0)
            $0.removeFromSuperview()
        }
        for name in names {
            let label = PaddingLabel()
            label.text = name
            label.insets = UIEdgeInsets(top: 2, left: 7, bottom: 2, right: 7)
            label.font = .systemFont(ofSize: 10, weight: .medium)
            label.textColor = UIColor(hexStr: "#D5923F")
            label.backgroundColor = UIColor(hexStr: "#FFF9DD")
            label.cornerRadius = 4
            label.clipsToBounds = true
            label.setContentCompressionResistancePriority(.required, for: .horizontal)
            tagStackView.addArrangedSubview(label)
        }
        tagScrollView.isHidden = names.isEmpty
    }

    private static func orderedPoints(_ points: [SchedulePointModel]) -> [SchedulePointModel] {
        guard points.count > 1 else { return points }
        let sequences = points.map(\.sequence)
        guard Set(sequences).count == points.count else { return points }
        return points.sorted { $0.sequence < $1.sequence }
    }

    private static func locationName(_ point: SchedulePointModel?, maximumCharacters: Int? = nil) -> String {
        let name: String
        if let point, !point.street.isEmpty {
            name = point.street
        } else if let point, !point.formatted_address.isEmpty {
            name = point.formatted_address
        } else {
            name = "暂无地点"
        }
        guard let maximumCharacters, name.count > maximumCharacters else { return name }
        return String(name.prefix(maximumCharacters)) + "..."
    }

    private static func durationText(from start: SchedulePointModel?, to end: SchedulePointModel?) -> String {
        guard let start, let end,
              start.id != end.id,
              end.expected_timestamp > start.expected_timestamp else { return "--" }
        let minutes = max(1, (end.expected_timestamp - start.expected_timestamp) / 60_000)
        let hours = minutes / 60
        let remainder = minutes % 60
        return hours > 0 ? "\(hours)小时\(remainder)分" : "\(minutes)分钟"
    }
}

private final class GroupItineraryDashLineView: UIView {
    override func layoutSubviews() {
        super.layoutSubviews()
        layer.sublayers?.forEach { if $0 is CAShapeLayer { $0.removeFromSuperlayer() } }

        let line = CAShapeLayer()
        line.strokeColor = UIColor(hexStr: "#D6D6D6").cgColor
        line.lineWidth = 1.5
        line.lineDashPattern = [6, 6]
        let path = UIBezierPath()
        path.move(to: CGPoint(x: 0, y: bounds.midY))
        path.addLine(to: CGPoint(x: bounds.maxX, y: bounds.midY))
        line.path = path.cgPath
        layer.addSublayer(line)
    }
}

private final class PaddingLabel: UILabel {
    var insets = UIEdgeInsets.zero

    override func drawText(in rect: CGRect) {
        super.drawText(in: rect.inset(by: insets))
    }

    override var intrinsicContentSize: CGSize {
        let size = super.intrinsicContentSize
        return CGSize(width: size.width + insets.left + insets.right,
                      height: size.height + insets.top + insets.bottom)
    }
}