//
//  AppUsageReportView.swift
//  QuickLocation
//

import UIKit
import Kingfisher

final class AppUsageReportView: UIView {

    lazy var navView = BaseNavigationView(title: "APP报告")
    let memberCV: UICollectionView = {
        let layout = UICollectionViewFlowLayout()
        layout.scrollDirection = .horizontal
        layout.itemSize = CGSize(width: 61, height: 90)
        layout.minimumLineSpacing = 12
        let view = UICollectionView(frame: .zero, collectionViewLayout: layout)
        view.backgroundColor = .white
        view.showsHorizontalScrollIndicator = false
        view.contentInset = UIEdgeInsets(top: 0, left: 12, bottom: 0, right: 12)
        view.register(GroupMemberListCell.self)
        view.applyAppUsageReportCardStyle(cornerRadius: 20)
        return view
    }()

    var onPeriodChanged: ((AppUsageReportPeriod) -> Void)?

    private let navBgView = UIImageView(image: UIImage(named: "Common/navBar_bg_2"))
    private let scrollView = UIScrollView()
    private let contentView = UIView()
    private let frequentSection = AppUsageFrequentSectionView()
    private let durationSection = AppUsageDurationSectionView()

    override init(frame: CGRect) {
        super.init(frame: frame)
        backgroundColor = UIColor(hexStr: "#FAFAFA")
        setupUI()
        bindPeriodControls()
    }

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

    func apply(_ snapshot: AppUsageReportViewModel.Snapshot) {
        frequentSection.setPeriod(snapshot.period)
        durationSection.setPeriod(snapshot.period)
        frequentSection.configure(apps: snapshot.apps, period: snapshot.period, state: snapshot.state)
        durationSection.configure(
            apps: snapshot.apps,
            totalUsageTime: snapshot.totalUsageTime,
            period: snapshot.period,
            state: snapshot.state
        )
    }

    private func bindPeriodControls() {
        let onChange: (AppUsageReportPeriod) -> Void = { [weak self] period in
            self?.onPeriodChanged?(period)
        }
        frequentSection.onPeriodChanged = onChange
        durationSection.onPeriodChanged = onChange
    }

    private func setupUI() {
        addSubview(navBgView)
        addSubview(navView)
        navBgView.contentMode = .scaleAspectFill
        navBgView.layoutChain.edges(excludingEdge: .bottom).heightToWidth(160 / 375)
        navView.layoutChain.top().edgesHorzontal().height(kNaviHeight)

        addSubview(scrollView)
        scrollView.showsVerticalScrollIndicator = false
        scrollView.layoutChain.topToBottomOfView(navView).edgesHorzontal().bottom()
        scrollView.addSubview(contentView)
        contentView.layoutChain.edges().widthToView(scrollView)

        contentView.addSubview(memberCV)
        memberCV.layoutChain.top(8).edgesHorzontal(15).height(100)

        contentView.addSubview(frequentSection)
        frequentSection.layoutChain.topToBottomOfView(memberCV, offset: 14).edgesHorzontal(15).height(253)

        contentView.addSubview(durationSection)
        durationSection.layoutChain
            .topToBottomOfView(frequentSection, offset: 14)
            .edgesHorzontal(15)
            .height(220)
            .bottom(24 + kSafeBottomMargin)
    }
}

private final class AppUsageSectionIconView: UIView {

    private let iconView = UIImageView()

    init(symbolName: String) {
        super.init(frame: .zero)
        backgroundColor = UIColor(hexStr: "#293445")
        iconView.image = UIImage(
            systemName: symbolName,
            withConfiguration: UIImage.SymbolConfiguration(pointSize: 9, weight: .bold)
        )
        iconView.tintColor = .white
        iconView.contentMode = .scaleAspectFit
        addSubview(iconView)
        iconView.layoutChain.centerX().centerY().width(10).height(10)
    }

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

    override func layoutSubviews() {
        super.layoutSubviews()
        layer.cornerRadius = min(bounds.width, bounds.height) / 2
    }
}

private enum AppUsageReportStyle {
    static func cardTitle(_ title: String) -> NSAttributedString {
        let attributedText = NSMutableAttributedString(
            string: "✦  \(title)",
            attributes: [
                .font: UIFont.systemFont(ofSize: 13, weight: .semibold),
                .foregroundColor: UIColor(hexStr: "#293445")
            ]
        )
        attributedText.addAttribute(
            .foregroundColor,
            value: UIColor(hexStr: "#A9F33D"),
            range: NSRange(location: 0, length: 1)
        )
        return attributedText
    }
}

private final class AppUsageFrequentSectionView: UIView {

    var onPeriodChanged: ((AppUsageReportPeriod) -> Void)?

    private let titleIcon = AppUsageSectionIconView(symbolName: "heart.fill")
    private let titleLab = UILabel()
    private let cardView = UIView()
    private let cardTitleLab = UILabel()
    private let periodControl = AppUsagePeriodControl()
    private let rowsStack = UIStackView()
    private let statusLab = UILabel()

    override init(frame: CGRect) {
        super.init(frame: frame)
        setupUI()
        periodControl.onChanged = { [weak self] period in
            self?.onPeriodChanged?(period)
        }
    }

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

    func setPeriod(_ period: AppUsageReportPeriod) {
        periodControl.setPeriod(period)
    }

    func configure(
        apps: [AppUsageReportViewModel.AppItem],
        period: AppUsageReportPeriod,
        state: AppUsageReportViewModel.ContentState
    ) {
        rowsStack.arrangedSubviews.forEach {
            rowsStack.removeArrangedSubview($0)
            $0.removeFromSuperview()
        }

        let statusText = AppUsageReportStatus.text(for: state)
        statusLab.text = statusText
        statusLab.isHidden = statusText == nil
        rowsStack.isHidden = statusText != nil

        guard statusText == nil else { return }
        for app in apps {
            let row = AppUsageRankRowView()
            row.configure(app: app, maximumUsageSeconds: period.maximumUsageSeconds)
            row.layoutChain.height(20)
            rowsStack.addArrangedSubview(row)
        }
    }

    private func setupUI() {
        addSubview(titleIcon)
        titleIcon.layoutChain.top().left().width(18).height(18)

        titleLab.text = "经常使用"
        titleLab.font = .systemFont(ofSize: 16, weight: .bold)
        titleLab.textColor = UIColor(hexStr: "#293445")
        addSubview(titleLab)
        titleLab.layoutChain.leftToRightOfView(titleIcon, offset: 7).centerY(titleIcon)

        cardView.backgroundColor = .white
        cardView.applyAppUsageReportCardStyle(cornerRadius: 20)
        addSubview(cardView)
        cardView.layoutChain.topToBottomOfView(titleIcon, offset: 12).edgesHorzontal().bottom()

        cardTitleLab.attributedText = AppUsageReportStyle.cardTitle("最爱使用TOP5")
        cardView.addSubview(cardTitleLab)
        cardTitleLab.layoutChain.top(22).left(20)

        cardView.addSubview(periodControl)
        periodControl.layoutChain.top(12).right(14).width(110).height(32)

        rowsStack.axis = .vertical
        rowsStack.spacing = 12
        cardView.addSubview(rowsStack)
        rowsStack.layoutChain.top(62).left(20).right(14)

        statusLab.font = .systemFont(ofSize: 14, weight: .medium)
        statusLab.textColor = UIColor(hexStr: "#9CA3AF")
        statusLab.textAlignment = .center
        statusLab.numberOfLines = 0
        cardView.addSubview(statusLab)
        statusLab.layoutChain.centerX().centerY(cardView, offset: 16).left(24).right(24)
    }

}

private final class AppUsageDurationSectionView: UIView {

    var onPeriodChanged: ((AppUsageReportPeriod) -> Void)?

    private let titleIcon = AppUsageSectionIconView(symbolName: "clock.fill")
    private let titleLab = UILabel()
    private let cardView = UIView()
    private let cardTitleLab = UILabel()
    private let periodControl = AppUsagePeriodControl()
    private let donutView = AppUsageReportDonutView()
    private let totalTimeLab = UILabel()
    private let totalHintLab = UILabel()
    private let legendStack = UIStackView()
    private let statusLab = UILabel()

    override init(frame: CGRect) {
        super.init(frame: frame)
        setupUI()
        periodControl.onChanged = { [weak self] period in
            self?.onPeriodChanged?(period)
        }
    }

    required init?(coder: NSCoder) { fatalError("init(coder:)") }

    func setPeriod(_ period: AppUsageReportPeriod) {
        periodControl.setPeriod(period)
    }

    func configure(
        apps: [AppUsageReportViewModel.AppItem],
        totalUsageTime: Int,
        period: AppUsageReportPeriod,
        state: AppUsageReportViewModel.ContentState
    ) {
        legendStack.arrangedSubviews.forEach {
            legendStack.removeArrangedSubview($0)
            $0.removeFromSuperview()
        }

        let statusText = AppUsageReportStatus.text(for: state)
        statusLab.text = statusText
        statusLab.isHidden = statusText == nil
        donutView.isHidden = statusText != nil
        totalTimeLab.isHidden = statusText != nil
        totalHintLab.isHidden = statusText != nil
        legendStack.isHidden = statusText != nil

        guard statusText == nil else {
            donutView.setSegments(ratios: [], colors: [])
            return
        }

        totalTimeLab.text = AppUsageReportFormat.durationText(seconds: totalUsageTime)
        donutView.setSegments(ratios: apps.map { CGFloat($0.usageTime) }, colors: apps.map(\.color))
        for app in apps {
            let row = AppUsageLegendRowView()
            row.configure(
                app: app,
                progress: CGFloat(app.usageTime) / CGFloat(period.maximumUsageSeconds)
            )
            row.layoutChain.height(20)
            legendStack.addArrangedSubview(row)
        }
    }

    private func setupUI() {
        addSubview(titleIcon)
        titleIcon.layoutChain.top().left().width(18).height(18)

        titleLab.text = "使用时长"
        titleLab.font = .systemFont(ofSize: 16, weight: .bold)
        titleLab.textColor = UIColor(hexStr: "#293445")
        addSubview(titleLab)
        titleLab.layoutChain.leftToRightOfView(titleIcon, offset: 7).centerY(titleIcon)

        cardView.backgroundColor = .white
        cardView.applyAppUsageReportCardStyle(cornerRadius: 20)
        addSubview(cardView)
        cardView.layoutChain.topToBottomOfView(titleIcon, offset: 12).edgesHorzontal().bottom()

        cardTitleLab.attributedText = AppUsageReportStyle.cardTitle("App使用详情")
        cardView.addSubview(cardTitleLab)
        cardTitleLab.layoutChain.top(22).left(20)

        cardView.addSubview(periodControl)
        periodControl.layoutChain.top(12).right(14).width(110).height(32)

        cardView.addSubview(donutView)
        donutView.layoutChain.left(20).top(56).width(122).height(122)

        totalTimeLab.font = .systemFont(ofSize: 16, weight: .semibold)
        totalTimeLab.textColor = UIColor(hexStr: "#293445")
        totalTimeLab.textAlignment = .center
        cardView.addSubview(totalTimeLab)
        totalTimeLab.layoutChain.centerX(donutView).centerY(donutView, offset: -8)

        totalHintLab.text = "总计"
        totalHintLab.font = .systemFont(ofSize: 10, weight: .medium)
        totalHintLab.textColor = UIColor(hexStr: "#767676")
        totalHintLab.textAlignment = .center
        cardView.addSubview(totalHintLab)
        totalHintLab.layoutChain.centerX(donutView).topToBottomOfView(totalTimeLab, offset: 4)

        legendStack.axis = .vertical
        legendStack.spacing = 5
        cardView.addSubview(legendStack)
        legendStack.layoutChain
            .top(54)
            .left(154)
            .right(14)

        statusLab.font = .systemFont(ofSize: 14, weight: .medium)
        statusLab.textColor = UIColor(hexStr: "#9CA3AF")
        statusLab.textAlignment = .center
        statusLab.numberOfLines = 0
        cardView.addSubview(statusLab)
        statusLab.layoutChain.centerX().centerY(cardView, offset: 18).left(24).right(24)
    }
}

private final class AppUsagePeriodControl: UIView {

    var onChanged: ((AppUsageReportPeriod) -> Void)?

    private let backgroundView = UIView()
    private let monthButton = UIButton(type: .custom)
    private let weekButton = UIButton(type: .custom)
    private var period: AppUsageReportPeriod = .week

    override init(frame: CGRect) {
        super.init(frame: frame)
        backgroundColor = UIColor(hexStr: "#EEEEEE")
        cornerRadius = 16
        setupUI()
        setPeriod(.week)
    }

    required init?(coder: NSCoder) { fatalError("init(coder:)") }

    func setPeriod(_ period: AppUsageReportPeriod) {
        self.period = period
        let selectedColor = UIColor(hexStr: "#293445")
        let normalColor = UIColor(hexStr: "#8C8C8C")
        monthButton.setTitleColor(period == .month ? selectedColor : normalColor, for: .normal)
        weekButton.setTitleColor(period == .week ? selectedColor : normalColor, for: .normal)
        backgroundView.frame = period == .month
            ? CGRect(x: 3, y: 3, width: bounds.width / 2 - 3, height: bounds.height - 6)
            : CGRect(x: bounds.width / 2, y: 3, width: bounds.width / 2 - 3, height: bounds.height - 6)
        setNeedsLayout()
    }

    override func layoutSubviews() {
        super.layoutSubviews()
        let width = bounds.width / 2 - 4
        backgroundView.frame = period == .month
            ? CGRect(x: 3, y: 3, width: width + 1, height: bounds.height - 6)
            : CGRect(x: bounds.width / 2, y: 3, width: width + 1, height: bounds.height - 6)
    }

    private func setupUI() {
        backgroundView.backgroundColor = .white
        backgroundView.cornerRadius = 13
        addSubview(backgroundView)
        sendSubviewToBack(backgroundView)

        [monthButton, weekButton].forEach {
            $0.titleLabel?.font = .systemFont(ofSize: 14, weight: .medium)
            addSubview($0)
        }
        monthButton.setTitle("月", for: .normal)
        weekButton.setTitle("周", for: .normal)
        monthButton.layoutChain.left().top().bottom().widthToView(self, multiplier: 0.5)
        weekButton.layoutChain.right().top().bottom().widthToView(self, multiplier: 0.5)
        monthButton.addTarget(self, action: #selector(selectMonth), for: .touchUpInside)
        weekButton.addTarget(self, action: #selector(selectWeek), for: .touchUpInside)
    }

    @objc private func selectMonth() {
        guard period != .month else { return }
        onChanged?(.month)
    }

    @objc private func selectWeek() {
        guard period != .week else { return }
        onChanged?(.week)
    }
}

private final class AppUsageRankRowView: UIView {

    private var progressRatio: CGFloat = 0
    private var progressConstraint: NSLayoutConstraint?
    private let rankLab = UILabel()
    private let iconView = UIImageView()
    private let nameLab = UILabel()
    private let trackView = UIView()
    private let fillView = UIView()
    private let percentageLab = UILabel()

    override init(frame: CGRect) {
        super.init(frame: frame)
        setupUI()
    }

    required init?(coder: NSCoder) { fatalError("init(coder:)") }

    func configure(app: AppUsageReportViewModel.AppItem, maximumUsageSeconds: Int) {
        rankLab.text = "\(app.rank)"
        nameLab.text = app.name
        let periodProgress = min(max(CGFloat(app.usageTime) / CGFloat(maximumUsageSeconds), 0), 1)
        percentageLab.text = "\(Int((periodProgress * 100).rounded()))%"
        iconView.kf.cancelDownloadTask()
        iconView.image = UIImage(named: "LockDistract/app_unknown")
        if let url = URL(string: app.iconURL), !app.iconURL.isEmpty {
            iconView.kf.setImage(with: url, placeholder: iconView.image)
        }
        progressRatio = periodProgress
        setNeedsLayout()
    }

    override func layoutSubviews() {
        super.layoutSubviews()
        progressConstraint?.isActive = false
        progressConstraint = fillView.widthAnchor.constraint(equalTo: trackView.widthAnchor, multiplier: progressRatio)
        progressConstraint?.isActive = true
    }

    private func setupUI() {
        rankLab.font = .systemFont(ofSize: 12, weight: .bold)
        rankLab.textColor = UIColor(hexStr: "#687385")
        rankLab.textAlignment = .center
        addSubview(rankLab)
        rankLab.layoutChain.left().centerY().width(14)

        iconView.backgroundColor = UIColor(hexStr: "#F4F6F8")
        iconView.image = UIImage(named: "LockDistract/app_unknown")
        iconView.contentMode = .scaleAspectFill
        iconView.cornerRadius = 4
        iconView.clipsToBounds = true
        addSubview(iconView)
        iconView.layoutChain.leftToRightOfView(rankLab, offset: 8).centerY().width(16).height(16)

        nameLab.font = .systemFont(ofSize: 11, weight: .medium)
        nameLab.textColor = UIColor(hexStr: "#4B5563")
        nameLab.lineBreakMode = .byTruncatingTail
        addSubview(nameLab)
        nameLab.layoutChain.leftToRightOfView(iconView, offset: 7).centerY().width(62)

        percentageLab.font = .systemFont(ofSize: 10, weight: .regular)
        percentageLab.textColor = UIColor(hexStr: "#A8A8A8")
        percentageLab.textAlignment = .right
        addSubview(percentageLab)
        percentageLab.layoutChain.right().centerY().width(34)

        trackView.backgroundColor = UIColor(hexStr: "#DDF3FF")
        trackView.cornerRadius = 2
        addSubview(trackView)
        trackView.layoutChain.leftToRightOfView(nameLab, offset: 8).rightToLeftOfView(percentageLab, offset: -8).centerY().height(4)

        fillView.backgroundColor = UIColor(hexStr: "#5BC5F7")
        fillView.cornerRadius = 2
        trackView.addSubview(fillView)
        fillView.layoutChain.left().top().bottom()
    }
}

private final class AppUsageLegendRowView: UIView {

    private var progressRatio: CGFloat = 0
    private var progressConstraint: NSLayoutConstraint?
    private let colorDot = UIView()
    private let iconView = UIImageView()
    private let nameLab = UILabel()
    private let trackView = UIView()
    private let fillView = UIView()
    private let durationLab = UILabel()

    override init(frame: CGRect) {
        super.init(frame: frame)
        setupUI()
    }

    required init?(coder: NSCoder) { fatalError("init(coder:)") }

    func configure(app: AppUsageReportViewModel.AppItem, progress: CGFloat) {
        colorDot.backgroundColor = app.color
        nameLab.text = app.name
        durationLab.text = app.durationText
        iconView.kf.cancelDownloadTask()
        iconView.image = UIImage(named: "LockDistract/app_unknown")
        if let url = URL(string: app.iconURL), !app.iconURL.isEmpty {
            iconView.kf.setImage(with: url, placeholder: iconView.image)
        }
        progressRatio = max(0, min(progress, 1))
        setNeedsLayout()
    }

    override func layoutSubviews() {
        super.layoutSubviews()
        progressConstraint?.isActive = false
        progressConstraint = fillView.widthAnchor.constraint(equalTo: trackView.widthAnchor, multiplier: progressRatio)
        progressConstraint?.isActive = true
    }

    private func setupUI() {
        colorDot.cornerRadius = 3
        addSubview(colorDot)
        colorDot.layoutChain.left().centerY().width(6).height(6)

        iconView.backgroundColor = UIColor(hexStr: "#F4F6F8")
        iconView.image = UIImage(named: "LockDistract/app_unknown")
        iconView.contentMode = .scaleAspectFill
        iconView.cornerRadius = 4
        iconView.clipsToBounds = true
        addSubview(iconView)
        iconView.layoutChain.leftToRightOfView(colorDot, offset: 7).centerY().width(16).height(16)

        durationLab.font = .systemFont(ofSize: 10, weight: .regular)
        durationLab.textColor = UIColor(hexStr: "#A8A8A8")
        durationLab.textAlignment = .right
        addSubview(durationLab)
        durationLab.layoutChain.right().centerY().width(42)

        nameLab.font = .systemFont(ofSize: 10, weight: .medium)
        nameLab.textColor = UIColor(hexStr: "#4B5563")
        nameLab.lineBreakMode = .byTruncatingTail
        addSubview(nameLab)
        nameLab.layoutChain.leftToRightOfView(iconView, offset: 6).centerY().width(42)

        trackView.backgroundColor = UIColor(hexStr: "#DDF3FF")
        trackView.cornerRadius = 2
        addSubview(trackView)
        trackView.layoutChain.leftToRightOfView(nameLab, offset: 5).rightToLeftOfView(durationLab, offset: -7).centerY().height(4)

        fillView.backgroundColor = UIColor(hexStr: "#5BC5F7")
        fillView.cornerRadius = 2
        trackView.addSubview(fillView)
        fillView.layoutChain.left().top().bottom()
    }
}

private final class AppUsageReportDonutView: UIView {

    private var segmentLayers: [CAShapeLayer] = []
    private var ratios: [CGFloat] = []
    private var colors: [UIColor] = []
    private let lineWidth: CGFloat = 18

    func setSegments(ratios: [CGFloat], colors: [UIColor]) {
        self.ratios = ratios
        self.colors = colors
        setNeedsLayout()
    }

    override func layoutSubviews() {
        super.layoutSubviews()
        segmentLayers.forEach { $0.removeFromSuperlayer() }
        segmentLayers.removeAll()
        guard !ratios.isEmpty, !colors.isEmpty, bounds.width > 0 else { return }

        let total = max(ratios.reduce(0, +), 0.001)
        let radius = min(bounds.width, bounds.height) / 2 - lineWidth / 2
        let center = CGPoint(x: bounds.midX, y: bounds.midY)
        var startAngle = -CGFloat.pi / 2
        let segmentGap: CGFloat = ratios.count > 1 ? 0.025 : 0
        for (index, ratio) in ratios.enumerated() {
            let sweep = ratio / total * 2 * CGFloat.pi
            guard sweep > 0.001 else { continue }
            let gap = min(segmentGap, sweep * 0.25)
            let path = UIBezierPath(
                arcCenter: center,
                radius: radius,
                startAngle: startAngle + gap,
                endAngle: startAngle + sweep - gap,
                clockwise: true
            )
            let layer = CAShapeLayer()
            layer.path = path.cgPath
            layer.fillColor = UIColor.clear.cgColor
            layer.strokeColor = colors[index % colors.count].cgColor
            layer.lineWidth = lineWidth
            layer.lineCap = .butt
            self.layer.addSublayer(layer)
            segmentLayers.append(layer)
            startAngle += sweep
        }
    }
}

private enum AppUsageReportFormat {
    static func durationText(seconds: Int) -> String {
        let hours = max(seconds, 0) / 3600
        let minutes = (max(seconds, 0) % 3600) / 60
        if hours > 0 {
            return minutes > 0 ? "\(hours)h \(minutes)m" : "\(hours)h"
        }
        return "\(minutes)m"
    }
}

private enum AppUsageReportStatus {
    static func text(for state: AppUsageReportViewModel.ContentState) -> String? {
        switch state {
        case .loading:
            return "正在加载..."
        case .empty:
            return "暂无APP使用记录"
        case .failure:
            return "加载失败，请稍后重试"
        case .content:
            return nil
        }
    }
}

private extension UIView {
    func applyAppUsageReportCardStyle(cornerRadius: CGFloat) {
        layer.cornerRadius = cornerRadius
        layer.masksToBounds = false
        layer.shadowColor = UIColor(hexStr: "#0F2846", alpha: 0.08).cgColor
        layer.shadowOffset = CGSize(width: 0, height: 2)
        layer.shadowOpacity = 1
        layer.shadowRadius = 9
    }
}