import UIKit

final class PeriodBloodFlowCoordinator {
    enum State { case idle, requiredSheet, animating, analysis, complete }

    private var state: State = .idle
    private var calendarLocked = false

    private let baseFillDuration: TimeInterval = 0.125
    private let durationUnit: TimeInterval = 0.0053
    private let previewHold: TimeInterval = 0.115
    private let overlapRatio: Double = 0.35
    private let minStaggerGap: TimeInterval = 0.118
    private let settleHold: TimeInterval = 0.170
    private let settleDuration: TimeInterval = 0.360

    func didTapYes(periodRange: PeriodRange) {
        UIImpactFeedbackGenerator(style: .heavy).impactOccurred()
        // 先展示白底中间态和黄色开始 icon；血流等弹窗确定后再播放。
        showWhitePreviewState(periodRange: periodRange)
        showStartIcon(periodRange: periodRange)
        state = .requiredSheet
        showRequiredPeriodSheet(
            onConfirm: { [weak self] in self?.confirmRequiredSheet(periodRange: periodRange) },
            onCancel: { [weak self] in self?.cancelRequiredSheet() }
        )
    }

    func didTapNo() {
        // 点击否不额外调用强震感，仅保留系统控件默认反馈。
        cancelPendingFlow()
        restoreUnrecordedState()
        state = .idle
    }

    private func confirmRequiredSheet(periodRange: PeriodRange) {
        hideRequiredPeriodSheet()
        expandTodayRecordList()
        calendarLocked = true
        state = .animating
        playBloodFlow(periodRange: periodRange) { [weak self] in
            self?.state = .analysis
            self?.showAnalysisBubble {
                self?.state = .complete
                self?.calendarLocked = false
            }
        }
    }

    private func cancelRequiredSheet() {
        hideRequiredPeriodSheet()
        restoreUnrecordedState()
        state = .idle
    }

    func didTapCalendarDate(_ date: Date) {
        guard !calendarLocked else { return }
        selectDate(date)
    }

    private func duration(for level: Double) -> TimeInterval {
        baseFillDuration + level * durationUnit
    }
}

struct PeriodRange { let dayCount: Int }