using System.Text.Json;
using FictionArchive.Service.ReportingService.Models.Database;
using FictionArchive.Service.Shared.MassTransit.Contracts;
using MassTransit;

namespace FictionArchive.Service.ReportingService.Services.Consumers;

public class JobStateChangedEventConsumer : IConsumer<JobStateChangedEvent>
{
    private readonly ReportingServiceDbContext _dbContext;
    private readonly ILogger<JobStateChangedEventConsumer> _logger;

    public JobStateChangedEventConsumer(
        ReportingServiceDbContext dbContext,
        ILogger<JobStateChangedEventConsumer> logger)
    {
        _dbContext = dbContext;
        _logger = logger;
    }

    public async Task Consume(ConsumeContext<JobStateChangedEvent> context)
    {
        var @event = context.Message;

        var job = await _dbContext.Jobs.FindAsync(@event.JobId);

        if (job == null)
        {
            job = new Job
            {
                Id = @event.JobId,
                JobType = @event.JobType,
                Status = @event.ToState,
                CreatedTime = @event.Timestamp,
                UpdatedTime = @event.Timestamp,
                Metadata = @event.Metadata != null
                    ? JsonSerializer.SerializeToDocument(@event.Metadata)
                    : null
            };
            _dbContext.Jobs.Add(job);
        }
        else
        {
            job.Status = @event.ToState;
            job.UpdatedTime = @event.Timestamp;

            if (@event.Error != null)
            {
                job.ErrorMessage = @event.Error;
            }

            if (@event.ToState is "Completed" or "Failed")
            {
                job.CompletedTime = @event.Timestamp;
            }
        }

        var historyEntry = new JobHistoryEntry
        {
            JobId = @event.JobId,
            FromState = @event.FromState,
            ToState = @event.ToState,
            Message = @event.Message,
            Error = @event.Error,
            Timestamp = @event.Timestamp
        };
        _dbContext.JobHistoryEntries.Add(historyEntry);

        await _dbContext.SaveChangesAsync();

        _logger.LogDebug("Recorded job state change: {JobId} {FromState} -> {ToState}",
            @event.JobId, @event.FromState, @event.ToState);
    }
}