//
//  ItineraryTableViewWrapper.swift
//  SportsTime
//
//  UIViewControllerRepresentable wrapper for ItineraryTableViewController
//

import SwiftUI

struct ItineraryTableViewWrapper<HeaderContent: View>: UIViewControllerRepresentable {
    @Environment(\.colorScheme) private var colorScheme

    let trip: Trip
    let games: [RichGame]
    let customItems: [CustomItineraryItem]
    let travelDayOverrides: [String: Int]
    let headerContent: HeaderContent

    // Callbacks
    var onTravelMoved: ((String, Int) -> Void)?
    var onCustomItemMoved: ((UUID, Int, Double) -> Void)?  // itemId, newDay, newSortOrder
    var onCustomItemTapped: ((CustomItineraryItem) -> Void)?
    var onCustomItemDeleted: ((CustomItineraryItem) -> Void)?
    var onAddButtonTapped: ((Int) -> Void)?  // Just day number

    init(
        trip: Trip,
        games: [RichGame],
        customItems: [CustomItineraryItem],
        travelDayOverrides: [String: Int],
        @ViewBuilder headerContent: () -> HeaderContent,
        onTravelMoved: ((String, Int) -> Void)? = nil,
        onCustomItemMoved: ((UUID, Int, Double) -> Void)? = nil,
        onCustomItemTapped: ((CustomItineraryItem) -> Void)? = nil,
        onCustomItemDeleted: ((CustomItineraryItem) -> Void)? = nil,
        onAddButtonTapped: ((Int) -> Void)? = nil
    ) {
        self.trip = trip
        self.games = games
        self.customItems = customItems
        self.travelDayOverrides = travelDayOverrides
        self.headerContent = headerContent()
        self.onTravelMoved = onTravelMoved
        self.onCustomItemMoved = onCustomItemMoved
        self.onCustomItemTapped = onCustomItemTapped
        self.onCustomItemDeleted = onCustomItemDeleted
        self.onAddButtonTapped = onAddButtonTapped
    }

    func makeCoordinator() -> Coordinator {
        Coordinator()
    }

    class Coordinator {
        var headerHostingController: UIHostingController<HeaderContent>?
    }

    func makeUIViewController(context: Context) -> ItineraryTableViewController {
        let controller = ItineraryTableViewController(style: .plain)
        controller.colorScheme = colorScheme
        controller.onTravelMoved = onTravelMoved
        controller.onCustomItemMoved = onCustomItemMoved
        controller.onCustomItemTapped = onCustomItemTapped
        controller.onCustomItemDeleted = onCustomItemDeleted
        controller.onAddButtonTapped = onAddButtonTapped

        // Set header with proper sizing
        let hostingController = UIHostingController(rootView: headerContent)
        hostingController.view.backgroundColor = .clear

        // Store in coordinator for later updates
        context.coordinator.headerHostingController = hostingController

        // Pre-size the header view
        hostingController.view.translatesAutoresizingMaskIntoConstraints = false
        let targetWidth = UIScreen.main.bounds.width
        let targetSize = CGSize(width: targetWidth, height: UIView.layoutFittingCompressedSize.height)
        let size = hostingController.view.systemLayoutSizeFitting(targetSize, withHorizontalFittingPriority: .required, verticalFittingPriority: .fittingSizeLevel)
        hostingController.view.frame = CGRect(origin: .zero, size: CGSize(width: targetWidth, height: max(size.height, 450)))
        hostingController.view.translatesAutoresizingMaskIntoConstraints = true

        controller.setTableHeader(hostingController.view)

        // Load initial data
        let (days, validRanges) = buildItineraryData()
        controller.reloadData(days: days, travelValidRanges: validRanges)

        return controller
    }

    func updateUIViewController(_ controller: ItineraryTableViewController, context: Context) {
        controller.colorScheme = colorScheme
        controller.onTravelMoved = onTravelMoved
        controller.onCustomItemMoved = onCustomItemMoved
        controller.onCustomItemTapped = onCustomItemTapped
        controller.onCustomItemDeleted = onCustomItemDeleted
        controller.onAddButtonTapped = onAddButtonTapped

        // Update header content by updating the hosting controller's rootView
        // This avoids recreating the view hierarchy and prevents infinite loops
        context.coordinator.headerHostingController?.rootView = headerContent

        let (days, validRanges) = buildItineraryData()
        controller.reloadData(days: days, travelValidRanges: validRanges)
    }

    // MARK: - Build Itinerary Data

    private func buildItineraryData() -> ([ItineraryDayData], [String: ClosedRange<Int>]) {
        let tripDays = calculateTripDays()
        var travelValidRanges: [String: ClosedRange<Int>] = [:]

        // Pre-calculate travel segment placements
        var travelByDay: [Int: TravelSegment] = [:]

        for segment in trip.travelSegments {
            let travelId = stableTravelAnchorId(segment)
            let fromCity = segment.fromLocation.name
            let toCity = segment.toLocation.name

            // Calculate valid range
            // Travel "on day N" appears BEFORE day N's header
            // So minDay must be AFTER the last game day in departure city
            let lastGameInFromCity = findLastGameDay(in: fromCity, tripDays: tripDays)
            let firstGameInToCity = findFirstGameDay(in: toCity, tripDays: tripDays)
            let minDay = max(lastGameInFromCity + 1, 1)  // Day AFTER last game in from city
            let maxDay = min(firstGameInToCity, tripDays.count)  // Can arrive same day as first game
            let validRange = minDay <= maxDay ? minDay...maxDay : maxDay...maxDay

            travelValidRanges[travelId] = validRange

            // Calculate default day
            let defaultDay: Int
            if lastGameInFromCity > 0 && lastGameInFromCity + 1 <= tripDays.count {
                defaultDay = lastGameInFromCity + 1
            } else if lastGameInFromCity > 0 {
                defaultDay = lastGameInFromCity
            } else {
                defaultDay = 1
            }

            // Use override if valid, otherwise use default
            if let overrideDay = travelDayOverrides[travelId], validRange.contains(overrideDay) {
                travelByDay[overrideDay] = segment
            } else {
                let clampedDefault = max(validRange.lowerBound, min(defaultDay, validRange.upperBound))
                travelByDay[clampedDefault] = segment
            }
        }

        // Build day data
        var days: [ItineraryDayData] = []

        for (index, dayDate) in tripDays.enumerated() {
            let dayNum = index + 1
            let gamesOnDay = gamesOn(date: dayDate)
            var items: [ItineraryRowItem] = []

            // Travel before this day (travel is stored on the destination day)
            let travelBefore: TravelSegment? = travelByDay[dayNum]

            // Custom items for this day - simply filter by day and sort by sortOrder
            // Note: Add button is now embedded in the day header row (not a separate item)
            let dayItems = customItems.filter { $0.day == dayNum }
                .sorted { $0.sortOrder < $1.sortOrder }

            for item in dayItems {
                items.append(ItineraryRowItem.customItem(item))
            }

            let dayData = ItineraryDayData(
                id: dayNum,
                dayNumber: dayNum,
                date: dayDate,
                games: gamesOnDay,
                items: items,
                travelBefore: travelBefore
            )
            days.append(dayData)
        }

        return (days, travelValidRanges)
    }

    // MARK: - Helper Methods

    private func calculateTripDays() -> [Date] {
        let start = trip.startDate
        let end = trip.endDate

        var days: [Date] = []
        var current = Calendar.current.startOfDay(for: start)
        let endDay = Calendar.current.startOfDay(for: end)

        while current <= endDay {
            days.append(current)
            current = Calendar.current.date(byAdding: .day, value: 1, to: current) ?? current
        }

        return days
    }

    private func gamesOn(date: Date) -> [RichGame] {
        let calendar = Calendar.current
        return games.filter { calendar.isDate($0.game.dateTime, inSameDayAs: date) }
            .sorted { $0.game.dateTime < $1.game.dateTime }
    }

    private func stableTravelAnchorId(_ segment: TravelSegment) -> String {
        "travel:\(segment.fromLocation.name.lowercased())->\(segment.toLocation.name.lowercased())"
    }

    private func findLastGameDay(in city: String, tripDays: [Date]) -> Int {
        var lastDay = 0

        for (index, dayDate) in tripDays.enumerated() {
            let dayNum = index + 1
            let gamesOnDay = gamesOn(date: dayDate)
            if gamesOnDay.contains(where: { cityMatches($0.stadium.city, searchCity: city) }) {
                lastDay = dayNum
            }
        }
        return lastDay
    }

    private func findFirstGameDay(in city: String, tripDays: [Date]) -> Int {
        for (index, dayDate) in tripDays.enumerated() {
            let dayNum = index + 1
            let gamesOnDay = gamesOn(date: dayDate)
            if gamesOnDay.contains(where: { cityMatches($0.stadium.city, searchCity: city) }) {
                return dayNum
            }
        }
        return tripDays.count
    }

    /// Fuzzy city matching - handles "Salt Lake City" vs "Salt Lake" etc.
    private func cityMatches(_ stadiumCity: String, searchCity: String) -> Bool {
        let stadiumLower = stadiumCity.lowercased().trimmingCharacters(in: .whitespacesAndNewlines)
        let searchLower = searchCity.lowercased().trimmingCharacters(in: .whitespacesAndNewlines)

        // Exact match
        if stadiumLower == searchLower {
            return true
        }

        // One contains the other
        if stadiumLower.contains(searchLower) || searchLower.contains(stadiumLower) {
            return true
        }

        // Word-based matching (handles "Salt Lake" matching "Salt Lake City")
        let stadiumWords = Set(stadiumLower.components(separatedBy: .whitespaces).filter { !$0.isEmpty })
        let searchWords = Set(searchLower.components(separatedBy: .whitespaces).filter { !$0.isEmpty })

        if !searchWords.isEmpty && searchWords.isSubset(of: stadiumWords) {
            return true
        }
        if !stadiumWords.isEmpty && stadiumWords.isSubset(of: searchWords) {
            return true
        }

        return false
    }
}