using System.Text.Json;
using Microsoft.Extensions.Caching.Memory;
using Microsoft.Extensions.Options;
using ProofOfConcept.Models;
using Pushover;
using SzakatsA.Result;

namespace ProofOfConcept.Services;

public interface IMessageProcessor
{
    Task ProcessMessage(string vin, string field, string value);
}

public class MessageProcessor : IMessageProcessor
{
    private readonly ILogger<MessageProcessor> logger;
    private MessageProcessorConfiguration configuration;

    private readonly IMemoryCache memoryCache;
    private readonly ZoneDeterminatorService zoneDeterminatorService;

    private readonly TeslaState teslaState;
    private readonly ParkingState parkingState;

    private readonly PushoverClient pushApi;
    
    public MessageProcessor(ILogger<MessageProcessor> logger, IOptions<MessageProcessorConfiguration> options, IMemoryCache memoryCache, ZoneDeterminatorService zoneDeterminatorService)
    {
        this.logger = logger;
        this.configuration = options.Value;

        this.memoryCache = memoryCache;
        this.zoneDeterminatorService = zoneDeterminatorService;
        
        this.teslaState = new TeslaState();
        this.parkingState = new ParkingState();
        
        this.pushApi = new PushoverClient(this.configuration.PushoverAPIKey);
    }
    
    public async Task ProcessMessage(string vin, string field, string value)
    {
        this.logger.LogTrace("Processing {Field} = {Value} for {VIN}...", field, value, vin);

        string[] validGears = [ "P", "R", "N", "D", "SNA" ];
        if (field == "gear" && validGears.Contains(value))
            this.teslaState.Gear = value;
        
        else if (field == "locked" && bool.TryParse(value, out bool locked))
            this.teslaState.Locked = locked;
        
        else if (field == "driverseatoccupied" && bool.TryParse(value, out bool driverSeatOccupied))
            this.teslaState.DriverSeatOccupied = driverSeatOccupied;
        
        else if (field == "location")
        {
            try
            {
                using var doc = JsonDocument.Parse(value);
                var root = doc.RootElement;

                this.teslaState.Latitude = root.GetProperty("latitude").GetDouble();
                this.teslaState.Longitude = root.GetProperty("longitude").GetDouble();
            }
            catch (Exception e)
            {
                this.logger.LogError("Invalid location data: {LocationValue}", value);
            }
        }

        this.logger.LogTrace("State updated");

        if (this.teslaState is { Gear: "P", Locked: true, DriverSeatOccupied: false })
            this.parkingState.SetCarParked();
        else
            this.parkingState.SetCarMoved();
        
        if (this.parkingState is { ParkingInProgress: false, CarParked: true })
            await StartParkingAsync(vin);
        
        else if (this.parkingState.ParkingInProgress && (this.teslaState.Gear != "P" || this.teslaState.DriverSeatOccupied || !this.teslaState.Locked))
            await StopParkingAsync(vin);
    }
    
    private async Task StartParkingAsync(string vin)
    {
        //Get parking zone
        Result<string> zoneLookupResult = await this.zoneDeterminatorService.DetermineZoneCodeAsync(this.teslaState.Latitude, this.teslaState.Longitude);
        bool sendNotification = this.configuration.VinNotifications.TryGetValue(vin, out string? pushoverToken);
        
        if (zoneLookupResult.IsSuccessful)
        {
            if (String.IsNullOrWhiteSpace(zoneLookupResult.Value))
            {
                // Push not a parking zone
                if (sendNotification)
                    this.pushApi.Send(pushoverToken, new PushoverMessage
                    {
                        Title = "Nem parkolózóna",
                        Message = $"Megálltál nem parkoló zónában, a GPS szerint: {this.teslaState.Latitude},{this.teslaState.Longitude}",
                        Priority = Priority.Normal,
                        Timestamp = DateTimeOffset.Now.ToLocalTime().ToString(),
                   });
                this.logger.LogInformation("Parking started in non-parking zone for {VIN}", vin);
            }

            // Push parking started in zone
            this.parkingState.SetParkingStarted();
            if (sendNotification)
                this.pushApi.Send(pushoverToken, new PushoverMessage
                {
                    Title = $"Parkolás elindult: {zoneLookupResult.Value}",
                    Message = $"Megálltál egy parkolási zónában, a GPS szerint: {this.teslaState.Latitude},{this.teslaState.Longitude}" + Environment.NewLine +
                              $"A zónatérkép szerint ez a {zoneLookupResult.Value} jelű zóna",
                    Priority = Priority.Normal,
                    Timestamp = DateTimeOffset.Now.ToLocalTime().ToString(),
                });
            this.logger.LogInformation("Parking started for {VIN}", vin);
        }
        else
            this.logger.LogError(zoneLookupResult.Exception, "Can't start parking: error while determining parking zone");
    }

    private async Task StopParkingAsync(string vin)
    {
        // Push parking stopped
        this.parkingState.SetParkingStopped();
        if (this.configuration.VinNotifications.TryGetValue(vin, out string? pushoverToken))
            this.pushApi.Send(pushoverToken, new PushoverMessage
            {
                Title = $"Parkolás leállt ({DateTimeOffset.Now.Subtract(this.parkingState.ParkingStartedAt!.Value).ToElapsed()})",
                Message = $"A {this.parkingState.ParkingStartedAt?.ToString("yyyy-MM-dd HH:mm")} -kor indult parkolásod leállt",
                Priority = Priority.Normal,
                Timestamp = DateTimeOffset.Now.ToLocalTime().ToString(),
            });
        this.logger.LogInformation("Parking stopped for {VIN}", vin);
    }
}

public class MessageProcessorConfiguration
{
    public string PushoverAPIKey { get; set; } = "acr9fqxafqeqjpr4apryh17m4ak24b";
    public Dictionary<string, string> VinNotifications { get; set; } = new Dictionary<string, string>() { { "5YJ3E7EB7KF291652", "u2ouaqqu5gd9f1bq3rmrtwriumaffu"} /*Zoli*/ };
}

file static class DateTimeOffsetExtensions
{
    public static string ToElapsed(this TimeSpan ts)
    {
        var parts = new List<string>();

        if (ts.Days > 0)
            parts.Add($"{ts.Days} nap");
        if (ts.Hours > 0)
            parts.Add($"{ts.Hours} óra");
        if (ts.Minutes > 0)
            parts.Add($"{ts.Minutes} perc");

        return string.Join(", ", parts);
    }
}