//
//  PDFGenerator.swift
//  SportsTime
//

import Foundation
import PDFKit
import UIKit

actor PDFGenerator {

    // MARK: - Generate PDF

    func generatePDF(for trip: Trip, games: [UUID: RichGame]) async throws -> Data {
        let pageWidth: CGFloat = 612  // Letter size
        let pageHeight: CGFloat = 792
        let margin: CGFloat = 50

        let pdfRenderer = UIGraphicsPDFRenderer(bounds: CGRect(x: 0, y: 0, width: pageWidth, height: pageHeight))

        let data = pdfRenderer.pdfData { context in
            var currentY: CGFloat = margin

            // Page 1: Cover
            context.beginPage()
            currentY = drawCoverPage(
                context: context,
                trip: trip,
                pageWidth: pageWidth,
                margin: margin
            )

            // Page 2+: Itinerary
            context.beginPage()
            currentY = margin
            currentY = drawItineraryHeader(
                context: context,
                y: currentY,
                pageWidth: pageWidth,
                margin: margin
            )

            for day in trip.itineraryDays() {
                // Check if we need a new page
                if currentY > pageHeight - 200 {
                    context.beginPage()
                    currentY = margin
                }

                currentY = drawDay(
                    context: context,
                    day: day,
                    games: games,
                    y: currentY,
                    pageWidth: pageWidth,
                    margin: margin
                )

                currentY += 20  // Space between days
            }

            // Summary page
            context.beginPage()
            drawSummaryPage(
                context: context,
                trip: trip,
                pageWidth: pageWidth,
                margin: margin
            )
        }

        return data
    }

    // MARK: - Cover Page

    private func drawCoverPage(
        context: UIGraphicsPDFRendererContext,
        trip: Trip,
        pageWidth: CGFloat,
        margin: CGFloat
    ) -> CGFloat {
        var y: CGFloat = 150

        // Title
        let titleAttributes: [NSAttributedString.Key: Any] = [
            .font: UIFont.boldSystemFont(ofSize: 32),
            .foregroundColor: UIColor.black
        ]

        let title = trip.name
        let titleRect = CGRect(x: margin, y: y, width: pageWidth - margin * 2, height: 50)
        (title as NSString).draw(in: titleRect, withAttributes: titleAttributes)
        y += 60

        // Date range
        let subtitleAttributes: [NSAttributedString.Key: Any] = [
            .font: UIFont.systemFont(ofSize: 18),
            .foregroundColor: UIColor.darkGray
        ]

        let dateRange = trip.formattedDateRange
        let dateRect = CGRect(x: margin, y: y, width: pageWidth - margin * 2, height: 30)
        (dateRange as NSString).draw(in: dateRect, withAttributes: subtitleAttributes)
        y += 50

        // Quick stats
        let statsAttributes: [NSAttributedString.Key: Any] = [
            .font: UIFont.systemFont(ofSize: 14),
            .foregroundColor: UIColor.gray
        ]

        let stats = """
        \(trip.stops.count) Cities  •  \(trip.totalGames) Games  •  \(trip.formattedTotalDistance)
        \(trip.tripDuration) Days  •  \(trip.formattedTotalDriving) Driving
        """

        let statsRect = CGRect(x: margin, y: y, width: pageWidth - margin * 2, height: 50)
        (stats as NSString).draw(in: statsRect, withAttributes: statsAttributes)
        y += 80

        // Cities list
        let citiesTitle = "Cities Visited"
        let citiesTitleRect = CGRect(x: margin, y: y, width: pageWidth - margin * 2, height: 25)
        (citiesTitle as NSString).draw(in: citiesTitleRect, withAttributes: [
            .font: UIFont.boldSystemFont(ofSize: 16),
            .foregroundColor: UIColor.black
        ])
        y += 30

        for city in trip.cities {
            let cityRect = CGRect(x: margin + 20, y: y, width: pageWidth - margin * 2 - 20, height: 20)
            ("• \(city)" as NSString).draw(in: cityRect, withAttributes: statsAttributes)
            y += 22
        }

        return y
    }

    // MARK: - Itinerary Header

    private func drawItineraryHeader(
        context: UIGraphicsPDFRendererContext,
        y: CGFloat,
        pageWidth: CGFloat,
        margin: CGFloat
    ) -> CGFloat {
        let headerAttributes: [NSAttributedString.Key: Any] = [
            .font: UIFont.boldSystemFont(ofSize: 24),
            .foregroundColor: UIColor.black
        ]

        let header = "Day-by-Day Itinerary"
        let headerRect = CGRect(x: margin, y: y, width: pageWidth - margin * 2, height: 35)
        (header as NSString).draw(in: headerRect, withAttributes: headerAttributes)

        return y + 50
    }

    // MARK: - Day Section

    private func drawDay(
        context: UIGraphicsPDFRendererContext,
        day: ItineraryDay,
        games: [UUID: RichGame],
        y: CGFloat,
        pageWidth: CGFloat,
        margin: CGFloat
    ) -> CGFloat {
        var currentY = y

        // Day header
        let dayHeaderAttributes: [NSAttributedString.Key: Any] = [
            .font: UIFont.boldSystemFont(ofSize: 16),
            .foregroundColor: UIColor.systemBlue
        ]

        let dayHeader = "Day \(day.dayNumber): \(day.formattedDate)"
        let dayHeaderRect = CGRect(x: margin, y: currentY, width: pageWidth - margin * 2, height: 25)
        (dayHeader as NSString).draw(in: dayHeaderRect, withAttributes: dayHeaderAttributes)
        currentY += 28

        // City
        if let city = day.primaryCity {
            let cityAttributes: [NSAttributedString.Key: Any] = [
                .font: UIFont.systemFont(ofSize: 14),
                .foregroundColor: UIColor.darkGray
            ]
            let cityRect = CGRect(x: margin + 10, y: currentY, width: pageWidth - margin * 2 - 10, height: 20)
            ("📍 \(city)" as NSString).draw(in: cityRect, withAttributes: cityAttributes)
            currentY += 24
        }

        // Travel segment
        if day.hasTravelSegment {
            for segment in day.travelSegments {
                let travelText = "🚗 \(segment.fromLocation.name) → \(segment.toLocation.name) (\(segment.formattedDistance), \(segment.formattedDuration))"
                let travelRect = CGRect(x: margin + 10, y: currentY, width: pageWidth - margin * 2 - 10, height: 20)
                (travelText as NSString).draw(in: travelRect, withAttributes: [
                    .font: UIFont.systemFont(ofSize: 12),
                    .foregroundColor: UIColor.gray
                ])
                currentY += 22
            }
        }

        // Games
        for gameId in day.gameIds {
            if let richGame = games[gameId] {
                let gameText = "⚾ \(richGame.fullMatchupDescription)"
                let gameRect = CGRect(x: margin + 10, y: currentY, width: pageWidth - margin * 2 - 10, height: 20)
                (gameText as NSString).draw(in: gameRect, withAttributes: [
                    .font: UIFont.systemFont(ofSize: 13),
                    .foregroundColor: UIColor.black
                ])
                currentY += 20

                let venueText = "   \(richGame.venueDescription) • \(richGame.game.gameTime)"
                let venueRect = CGRect(x: margin + 10, y: currentY, width: pageWidth - margin * 2 - 10, height: 18)
                (venueText as NSString).draw(in: venueRect, withAttributes: [
                    .font: UIFont.systemFont(ofSize: 11),
                    .foregroundColor: UIColor.gray
                ])
                currentY += 22
            }
        }

        // Rest day indicator
        if day.isRestDay {
            let restText = "😴 Rest Day"
            let restRect = CGRect(x: margin + 10, y: currentY, width: pageWidth - margin * 2 - 10, height: 20)
            (restText as NSString).draw(in: restRect, withAttributes: [
                .font: UIFont.italicSystemFont(ofSize: 12),
                .foregroundColor: UIColor.gray
            ])
            currentY += 22
        }

        // Separator line
        currentY += 5
        let path = UIBezierPath()
        path.move(to: CGPoint(x: margin, y: currentY))
        path.addLine(to: CGPoint(x: pageWidth - margin, y: currentY))
        UIColor.lightGray.setStroke()
        path.lineWidth = 0.5
        path.stroke()
        currentY += 10

        return currentY
    }

    // MARK: - Summary Page

    private func drawSummaryPage(
        context: UIGraphicsPDFRendererContext,
        trip: Trip,
        pageWidth: CGFloat,
        margin: CGFloat
    ) {
        var y: CGFloat = margin

        // Header
        let headerAttributes: [NSAttributedString.Key: Any] = [
            .font: UIFont.boldSystemFont(ofSize: 24),
            .foregroundColor: UIColor.black
        ]
        let header = "Trip Summary"
        let headerRect = CGRect(x: margin, y: y, width: pageWidth - margin * 2, height: 35)
        (header as NSString).draw(in: headerRect, withAttributes: headerAttributes)
        y += 50

        // Stats
        let statAttributes: [NSAttributedString.Key: Any] = [
            .font: UIFont.systemFont(ofSize: 14),
            .foregroundColor: UIColor.black
        ]

        let stats = [
            ("Total Duration", "\(trip.tripDuration) days"),
            ("Total Distance", trip.formattedTotalDistance),
            ("Total Driving Time", trip.formattedTotalDriving),
            ("Average Daily Driving", String(format: "%.1f hours", trip.averageDrivingHoursPerDay)),
            ("Cities Visited", "\(trip.stops.count)"),
            ("Games Attended", "\(trip.totalGames)"),
            ("Sports", trip.uniqueSports.map { $0.rawValue }.joined(separator: ", "))
        ]

        for (label, value) in stats {
            let labelRect = CGRect(x: margin, y: y, width: 200, height: 22)
            ("\(label):" as NSString).draw(in: labelRect, withAttributes: [
                .font: UIFont.boldSystemFont(ofSize: 13),
                .foregroundColor: UIColor.darkGray
            ])

            let valueRect = CGRect(x: margin + 200, y: y, width: pageWidth - margin * 2 - 200, height: 22)
            (value as NSString).draw(in: valueRect, withAttributes: statAttributes)
            y += 26
        }

        // Score (if available)
        if let score = trip.score {
            y += 20

            let scoreHeader = "Trip Score: \(score.scoreGrade) (\(score.formattedOverallScore)/100)"
            let scoreRect = CGRect(x: margin, y: y, width: pageWidth - margin * 2, height: 30)
            (scoreHeader as NSString).draw(in: scoreRect, withAttributes: [
                .font: UIFont.boldSystemFont(ofSize: 18),
                .foregroundColor: UIColor.systemGreen
            ])
        }

        // Footer
        y = 720
        let footerText = "Generated by Sport Travel Planner"
        let footerRect = CGRect(x: margin, y: y, width: pageWidth - margin * 2, height: 20)
        (footerText as NSString).draw(in: footerRect, withAttributes: [
            .font: UIFont.italicSystemFont(ofSize: 10),
            .foregroundColor: UIColor.lightGray
        ])
    }
}

// MARK: - Export Service

actor ExportService {
    private let pdfGenerator = PDFGenerator()

    func exportToPDF(trip: Trip, games: [UUID: RichGame]) async throws -> URL {
        let data = try await pdfGenerator.generatePDF(for: trip, games: games)

        let fileName = "\(trip.name.replacingOccurrences(of: " ", with: "_"))_\(Date().timeIntervalSince1970).pdf"
        let url = FileManager.default.temporaryDirectory.appendingPathComponent(fileName)

        try data.write(to: url)
        return url
    }

    func shareTrip(_ trip: Trip) -> URL? {
        // Generate a shareable deep link
        // In production, this would create a proper share URL
        let baseURL = "sportstime://trip/"
        return URL(string: baseURL + trip.id.uuidString)
    }
}