using LCU.Library.Internal.DispatcherModels.Enums;
using System.Collections.Generic;
namespace LCU.Api.Internal.Dispatcher.Services.DispatcherOperationServices;

public class IngestionService : IIngestionService
{
    private readonly IJobService _jobService;
    private readonly IWorkItemService _workItemService;
    private readonly IJobErrorRecipientService _jobErrorRecipientService;
    private readonly IJobTagService _jobTagService;

    public IngestionService(IJobService jobService,
                            IWorkItemService workItemService,
                            IJobErrorRecipientService jobErrorRecipientService,
                            IJobTagService jobTagService)
    {
        _jobService = jobService;
        _workItemService = workItemService;
        _jobErrorRecipientService = jobErrorRecipientService;
        _jobTagService = jobTagService;
    }

    public async Task HandleIngestionRequest(Job request)
    {
        try
        {
            ArgumentNullException.ThrowIfNull(request);
            var result = await PerformIngestion(request);

            if (!result)
            {
                throw new ServiceException("Failure to PerformIngestion.");
            }
        }
        catch (Exception exception)
        {
            Log.Error(exception, $"Failed to perform execution.");
            throw new ServiceException($"Failed to perform ingestion.");
        }
    }

    public async Task<bool> PerformIngestion(Job request)
    {
        try
        {
            if (request.IsNewJob)
            {
                return await SaveNewRequest(request);
            }

            return await UpdateRequest(request);
        }
        catch (Exception ex)
        {
            Log.Information(ex, $"Failed to perform ingestion.");
            return false;
        }
    }

    public async Task<bool> SaveNewRequest(Job request)
    {
        request = await _jobService.SaveAsync(request);
        if (request == null)
        {
            return false;
        }

        var updatedWorkItems = await _workItemService.PopulateActionFieldsAndUpdateList(request.WorkItems);
        if (updatedWorkItems == null)
        {
            return false;
        }

        return true;
    }

    public async Task<bool> UpdateRequest(Job request)
    {
        var existingJob = await _jobService.GetByIdAsync(request.JobId);

        await UpdateRequestWorkItems(request, existingJob);
        UpdateRequestErrorRecipients(request, existingJob);
        await UpdateRequestJobTags(request, existingJob);
        request.JobStatus = (request.NextRunTime == null && request.CronSchedule == null) ? JobStatus.Inactive : existingJob.JobStatus;

        var updatedJob = await _jobService.UpdateAsync(request);
        if (updatedJob == null)
        {
            return false;
        }

        return true;
    }

    public async Task UpdateRequestWorkItems(Job request, Job existingJob)
    {
        var removedWorkItems = existingJob.WorkItems.Where(wi =>
                                                     !request.WorkItems.Any(newWI =>
                                                              newWI.WorkItemId == wi.WorkItemId)).ToList();
        await _workItemService.DeleteList(removedWorkItems);

        var newWorkItems = request.WorkItems.Where(wi => wi.IsNewWorkItem).ToList();
        _workItemService.SaveList(newWorkItems);

        var updatedWorkItems = await _workItemService.PopulateActionFieldsAndUpdateList(request.WorkItems);
        if (updatedWorkItems == null)
        {
            throw new Exception($"WorkItem Error while Populating Action Fields and updating.");
        }
    }

    public void UpdateRequestErrorRecipients(Job request, Job existingJob)
    {
        var removedJobErrorRecipients = existingJob.JobErrorRecipients.Where(recipient =>
                                                     !request.JobErrorRecipients.Any(newRecipient =>
                                                              newRecipient.Recipient == recipient.Recipient)).ToList();
        _jobErrorRecipientService.DeleteList(removedJobErrorRecipients);

        var newJobErrorRecipients = new List<JobErrorRecipient>();
        foreach (var recipient in request.JobErrorRecipients)
        {
            var jobErrorRecipient = existingJob.JobErrorRecipients.FirstOrDefault(existing =>
                                            existing.Recipient == recipient.Recipient);

            if (jobErrorRecipient == null)
            {
                newJobErrorRecipients.Add(recipient);
            }
        }

        _jobErrorRecipientService.SaveList(newJobErrorRecipients);
    }

    public async Task UpdateRequestJobTags(Job request, Job existingJob)
    {
        var removedJobTags = existingJob.JobTags.Where(tag =>
                                              !request.JobTags.Any(jobTags =>
                                                       jobTags.TagId == tag.TagId)).ToList();

        foreach (var tag in removedJobTags)
        {
            await _jobTagService.Delete(tag.JobTagId);
        }

        var newJobTags = new List<JobTag>();
        foreach (var tag in request.JobTags)
        {
            var existingTag = existingJob.JobTags.FirstOrDefault(existing =>
                                            existing.TagId == tag.TagId);

            if (existingTag == null)
            {
                newJobTags.Add(tag);
                var result = await _jobTagService.SaveAsync(tag);
            }

        }
    }
}