shoc-backend/SeaHaven.Services/Implementation/WorkOrderMediaService.cs

using Data.SeaHavenIndustries;
using Data.SeaHavenIndustries.Enums;
using SeaHaven.DataServices.Interfaces;
using SeaHaven.Services.DTOs;
using SeaHaven.Services.Exceptions;
using SeaHaven.Services.Helpers;
using SeaHaven.Services.Interfaces;

namespace SeaHaven.Services.Implementation
{
    public class WorkOrderMediaService : IWorkOrderMediaService
    {
        private readonly IWorkOrderMediaDataService _mediaData;
        private readonly IWorkOrderDetailDataService _detailData;
        private readonly IWorkOrderAuditService _auditService;

        public WorkOrderMediaService(
            IWorkOrderMediaDataService mediaData,
            IWorkOrderDetailDataService detailData,
            IWorkOrderAuditService auditService)
        {
            _mediaData = mediaData;
            _detailData = detailData;
            _auditService = auditService;
        }

        public async Task<IReadOnlyList<WorkOrderMediaFileDto>?> GetMediaAsync(
            int workOrderId,
            CancellationToken cancellationToken = default)
        {
            if (!await _detailData.ExistsAsync(workOrderId))
                return null;

            var workOrder = await _detailData.GetWorkOrderForMediaAsync(workOrderId);
            if (workOrder == null)
                return null;

            var attachments = await _detailData.GetAttachmentsAsync(workOrderId);
            return WorkOrderMediaProjection.ProjectAll(workOrder, attachments);
        }

        public async Task EnsureCanMutateMediaAsync(
            int workOrderId,
            string? actorId,
            CancellationToken cancellationToken = default)
        {
            EnsureAuthenticatedActor(actorId);
            await GetMutableWorkOrderAsync(workOrderId, cancellationToken);
        }

        public async Task<WorkOrderMediaFileDto> AddMediaAsync(
            int workOrderId,
            WorkOrderMediaCategory? category,
            string fileUrl,
            string? actorId,
            CancellationToken cancellationToken = default)
        {
            EnsureAuthenticatedActor(actorId);

            var resolvedCategory = category ?? WorkOrderMediaCategory.Extra;
            var workOrder = await GetMutableWorkOrderAsync(workOrderId, cancellationToken);

            if (resolvedCategory == WorkOrderMediaCategory.Completion)
            {
                throw new WorkOrderBoardValidationException(
                    "UseCompletionDocEndpoint",
                    "Completion documents must be uploaded via POST /api/workorders/{id}/completion-doc.");
            }

            if (resolvedCategory == WorkOrderMediaCategory.Before)
            {
                var oldBefore = workOrder.BeforPhotoAttachment;
                workOrder.BeforPhotoAttachment = fileUrl;
                await _auditService.StageFieldChangedAsync(
                    workOrderId, "BeforPhotoAttachment", oldBefore, fileUrl, actorId);
                await _mediaData.SaveAsync(cancellationToken);
                return new WorkOrderMediaFileDto
                {
                    Id = -1,
                    Category = resolvedCategory,
                    Url = fileUrl,
                    IsLegacy = true
                };
            }

            if (resolvedCategory == WorkOrderMediaCategory.After)
            {
                var oldAfter = workOrder.AfterPhotoAttachment;
                workOrder.AfterPhotoAttachment = fileUrl;
                await _auditService.StageFieldChangedAsync(
                    workOrderId, "AfterPhotoAttachment", oldAfter, fileUrl, actorId);
                await _mediaData.SaveAsync(cancellationToken);
                return new WorkOrderMediaFileDto
                {
                    Id = -2,
                    Category = resolvedCategory,
                    Url = fileUrl,
                    IsLegacy = true
                };
            }

            var attachment = new WorkOrderAttachments
            {
                WorkorderId = workOrderId,
                Attachments = fileUrl,
                Category = category.HasValue ? resolvedCategory : null,
                CreatedDate = DateTime.UtcNow,
                createdby = actorId
            };

            _mediaData.TrackAttachment(attachment);
            await _auditService.StageFieldChangedAsync(
                workOrderId,
                "MediaCategory",
                null,
                FormatMediaAuditValue(null, (attachment.Category ?? WorkOrderMediaCategory.Extra).ToString()),
                actorId);
            await _mediaData.SaveAsync(cancellationToken);

            return new WorkOrderMediaFileDto
            {
                Id = attachment.Id,
                Category = attachment.Category ?? WorkOrderMediaCategory.Extra,
                Url = fileUrl,
                UploadedAt = attachment.CreatedDate?.ToUniversalTime().ToString("o"),
                IsLegacy = false
            };
        }

        public async Task<WorkOrderMediaFileDto> UpdateMediaCategoryAsync(
            int workOrderId,
            int mediaId,
            WorkOrderMediaCategory category,
            string? workOrderVersion,
            string? actorId,
            CancellationToken cancellationToken = default)
        {
            EnsureAuthenticatedActor(actorId);

            if (mediaId <= 0)
                throw new WorkOrderBoardValidationException("InvalidMedia", "Legacy media cannot be categorized via this endpoint.");

            if (category == WorkOrderMediaCategory.Completion)
            {
                throw new WorkOrderBoardValidationException(
                    "UseCompletionDocEndpoint",
                    "Completion documents must be uploaded via POST /api/workorders/{id}/completion-doc.");
            }

            var workOrder = await GetMutableWorkOrderAsync(workOrderId, cancellationToken);
            ApplyExpectedVersion(workOrder, workOrderVersion);

            var attachment = await _mediaData.GetTrackedAttachmentAsync(mediaId, workOrderId, cancellationToken);
            if (attachment == null)
                throw new WorkOrderBoardValidationException("NotFound", "Media not found.");

            var priorCategory = (attachment.Category ?? WorkOrderMediaCategory.Extra).ToString();

            if (category == WorkOrderMediaCategory.Before || category == WorkOrderMediaCategory.After)
            {
                var url = attachment.Attachments ?? "";
                if (category == WorkOrderMediaCategory.Before)
                    workOrder.BeforPhotoAttachment = url;
                else
                    workOrder.AfterPhotoAttachment = url;

                attachment.IsDeleted = true;
                attachment.DeletionTime = DateTime.UtcNow;
                attachment.DeleterUserId = actorId;

                await _auditService.StageFieldChangedAsync(
                    workOrderId,
                    "MediaCategory",
                    FormatMediaAuditValue(mediaId, priorCategory),
                    FormatMediaAuditValue(mediaId, category.ToString()),
                    actorId);
                await _mediaData.SaveAsync(cancellationToken);

                return new WorkOrderMediaFileDto
                {
                    Id = category == WorkOrderMediaCategory.Before ? -1 : -2,
                    Category = category,
                    Url = url,
                    IsLegacy = true
                };
            }

            attachment.Category = category;
            _mediaData.MarkWorkOrderModified(workOrder);
            await _auditService.StageFieldChangedAsync(
                workOrderId,
                "MediaCategory",
                FormatMediaAuditValue(mediaId, priorCategory),
                FormatMediaAuditValue(mediaId, category.ToString()),
                actorId);
            await _mediaData.SaveAsync(cancellationToken);

            return new WorkOrderMediaFileDto
            {
                Id = attachment.Id,
                Category = attachment.Category ?? WorkOrderMediaCategory.Extra,
                Url = attachment.Attachments ?? "",
                UploadedAt = attachment.CreatedDate?.ToUniversalTime().ToString("o"),
                IsLegacy = false
            };
        }

        public async Task DeleteMediaAsync(
            int workOrderId,
            int mediaId,
            string? workOrderVersion,
            string? actorId,
            CancellationToken cancellationToken = default)
        {
            EnsureAuthenticatedActor(actorId);

            if (mediaId <= 0)
                throw new WorkOrderBoardValidationException("InvalidMedia", "Legacy media cannot be deleted via this endpoint.");

            var workOrder = await GetMutableWorkOrderAsync(workOrderId, cancellationToken);
            ApplyExpectedVersion(workOrder, workOrderVersion);

            var attachment = await _mediaData.GetTrackedAttachmentAsync(mediaId, workOrderId, cancellationToken);
            if (attachment == null)
                throw new WorkOrderBoardValidationException("NotFound", "Media not found.");

            var priorCategory = (attachment.Category ?? WorkOrderMediaCategory.Extra).ToString();
            attachment.IsDeleted = true;
            attachment.DeletionTime = DateTime.UtcNow;
            attachment.DeleterUserId = actorId;
            _mediaData.MarkWorkOrderModified(workOrder);

            await _auditService.StageFieldChangedAsync(
                workOrderId,
                "MediaCategory",
                FormatMediaAuditValue(mediaId, priorCategory),
                FormatMediaAuditValue(mediaId, "Deleted"),
                actorId);
            await _mediaData.SaveAsync(cancellationToken);
        }

        private async Task<WorkOrder> GetMutableWorkOrderAsync(int workOrderId, CancellationToken cancellationToken)
        {
            if (!await _detailData.ExistsAsync(workOrderId))
                throw new WorkOrderBoardValidationException("NotFound", "Work order not found.");

            var workOrder = await _mediaData.GetTrackedWorkOrderAsync(workOrderId, cancellationToken);
            if (workOrder == null)
                throw new WorkOrderBoardValidationException("NotFound", "Work order not found.");

            if (WorkOrderBoardMutationRules.IsReadOnly(workOrder.LifecycleStatus))
                throw new WorkOrderBoardValidationException("ReadOnly", "Work order is read-only in its current status.");

            return workOrder;
        }

        private void ApplyExpectedVersion(WorkOrder workOrder, string? workOrderVersion)
        {
            var expected = ParseRowVersion(workOrderVersion);
            if (expected == null)
                throw new WorkOrderBoardValidationException("WorkOrderVersionRequired", "workOrderVersion is required.");

            if (workOrder.RowVersion == null || !workOrder.RowVersion.AsSpan().SequenceEqual(expected))
                throw new WorkOrderBoardValidationException("ConcurrencyConflict", "Work order was modified. Refresh and retry.");

            _mediaData.SetExpectedWorkOrderVersion(workOrder, expected);
        }

        private static void EnsureAuthenticatedActor(string? actorId)
        {
            if (string.IsNullOrWhiteSpace(actorId))
                throw new WorkOrderBoardValidationException("Forbidden", "You are not allowed to mutate work order media.");
        }

        private static byte[]? ParseRowVersion(string? base64)
        {
            if (string.IsNullOrWhiteSpace(base64))
                return null;

            try
            {
                return Convert.FromBase64String(base64);
            }
            catch (FormatException)
            {
                throw new WorkOrderBoardValidationException("InvalidRowVersion", "Invalid workOrderVersion format.");
            }
        }

        private static string FormatMediaAuditValue(int? mediaId, string category)
            => mediaId.HasValue ? $"{mediaId.Value}:{category}" : category;
    }
}