using Data.SeaHavenIndustries;
using Microsoft.EntityFrameworkCore;
using SeaHaven.DataServices.Interfaces;

namespace SeaHaven.DataServices.Implementation
{
    public class VendorDocumentDataService : IVendorDocumentDataService
    {
        private readonly ApplicationDbContext _context;

        public VendorDocumentDataService(ApplicationDbContext context)
        {
            _context = context;
        }

        // Completion-document queries/version semantics exclude uplift evidence so that
        // supporting evidence never participates in completion versioning or replacement.
        private const string CompletionPurpose = "Completion";

        public async Task<IReadOnlyList<string>> ListActiveContentTypesForWorkOrderAsync(
            int workOrderId,
            int? excludingDocumentId,
            CancellationToken cancellationToken)
        {
            // Uplift evidence also records the latest completion id in ReplacesDocumentId, so only
            // a newer completion version supersedes a document.
            return await _context.VendorCompletionDocuments
                .AsNoTracking()
                .Where(document => document.WorkOrderId == workOrderId
                    && (document.IsDeleted == null || document.IsDeleted == false)
                    && (excludingDocumentId == null || document.Id != excludingDocumentId)
                    && !_context.VendorCompletionDocuments.Any(newer =>
                        newer.ReplacesDocumentId == document.Id
                        && newer.Purpose == CompletionPurpose
                        && (newer.IsDeleted == null || newer.IsDeleted == false)))
                .Select(document => document.ContentType)
                .ToListAsync(cancellationToken);
        }

        public async Task<IReadOnlyList<string>> ListActiveWorkOrderAttachmentUrlsAsync(
            int workOrderId,
            CancellationToken cancellationToken)
        {
            return await _context.workOrderAttachments
                .AsNoTracking()
                .Where(attachment => attachment.WorkorderId == workOrderId
                    && attachment.IsDeleted != true
                    && attachment.Attachments != null)
                .Select(attachment => attachment.Attachments!)
                .ToListAsync(cancellationToken);
        }

        public Task<VendorCompletionDocument?> GetLatestForDispatchAsync(int dispatchId, CancellationToken cancellationToken)
        {
            return _context.VendorCompletionDocuments
                .Where(document => document.DispatchId == dispatchId
                    && document.Purpose == CompletionPurpose)
                .OrderByDescending(document => document.Version)
                .FirstOrDefaultAsync(cancellationToken);
        }

        public Task<VendorCompletionDocument?> GetForVendorDispatchAsync(int documentId, int dispatchId, int vendorId, CancellationToken cancellationToken)
        {
            return _context.VendorCompletionDocuments
                .FirstOrDefaultAsync(document => document.Id == documentId
                    && document.DispatchId == dispatchId
                    && document.VendorId == vendorId
                    && document.Purpose == CompletionPurpose
                    && (document.IsDeleted == null || document.IsDeleted == false), cancellationToken);
        }

        public Task<VendorCompletionDocument?> GetMetadataForVendorDispatchAsync(int documentId, int dispatchId, int vendorId, CancellationToken cancellationToken)
        {
            return _context.VendorCompletionDocuments
                .AsNoTracking()
                .FirstOrDefaultAsync(document => document.Id == documentId
                    && document.DispatchId == dispatchId
                    && document.VendorId == vendorId
                    && (document.IsDeleted == null || document.IsDeleted == false), cancellationToken);
        }

        public Task<List<VendorCompletionDocument>> ListForVendorDispatchAsync(int dispatchId, int vendorId, CancellationToken cancellationToken)
        {
            return _context.VendorCompletionDocuments
                .Where(document => document.DispatchId == dispatchId
                    && document.VendorId == vendorId
                    && document.Purpose == CompletionPurpose
                    && (document.IsDeleted == null || document.IsDeleted == false))
                .OrderByDescending(document => document.Version)
                .ToListAsync(cancellationToken);
        }

        // SH-101: an uplift request > current requires a same-vendor, same-dispatch,
        // nondeleted UpliftEvidence document whose scan passed. This lookup enforces all of those.
        public Task<VendorCompletionDocument?> GetUpliftEvidenceAsync(int documentId, int dispatchId, int vendorId, CancellationToken cancellationToken)
        {
            return _context.VendorCompletionDocuments
                .FirstOrDefaultAsync(document => document.Id == documentId
                    && document.DispatchId == dispatchId
                    && document.VendorId == vendorId
                    && document.Purpose == "UpliftEvidence"
                    && document.ScanStatus == "Passed"
                    && (document.IsDeleted == null || document.IsDeleted == false), cancellationToken);
        }

        public async Task AddAsync(VendorCompletionDocument document, CancellationToken cancellationToken)
        {
            await _context.VendorCompletionDocuments.AddAsync(document, cancellationToken);
        }

        public Task SaveChangesAsync(CancellationToken cancellationToken)
        {
            return _context.SaveChangesAsync(cancellationToken);
        }
    }
}