refactor: create layout service to handle more explicit layout actions

Creates a new service `LayoutService` that will be used for more fine
grained explicit operations on the layout configurations.
Adds basic operations for pages in a layout.

commit-id:d6447eac

backend/src/Designer/Infrastructure/GitRepository/AltinnAppGitRepository.cs

@@ -359,6 +359,16 @@ public void DeleteTexts(string languageCode)
             }
         }
 
+        public async Task CreatePageLayoutFile(string layoutSetId, string pageId)
+        {
+            JsonObject defaultPageLayout = new()
+            {
+                ["$schema"] = LayoutSchemaUrl,
+                ["data"] = new JsonObject { ["layout"] = new JsonArray([]) }
+            };
+            await WriteObjectByRelativePathAsync(Path.Combine(LayoutsFolderName, layoutSetId, $"{LayoutsInSetFolderName}/{pageId}.json"), defaultPageLayout);
+        }
+
         /// <summary>
         /// Returns all the layouts for a specific layout set
         /// </summary>

backend/src/Designer/Infrastructure/ServiceRegistration.cs

@@ -76,6 +76,7 @@ public static IServiceCollection RegisterServiceImplementations(this IServiceCol
             services.AddTransient<IInstanceService, InstanceService>();
             services.AddTransient<IProcessModelingService, ProcessModelingService>();
             services.AddTransient<IImagesService, ImagesService>();
+            services.AddTransient<ILayoutService, LayoutService>();
             services.RegisterDatamodeling(configuration);
 
             return services;

backend/src/Designer/Models/Dto/Page.cs

@@ -0,0 +1,9 @@
+using System.Text.Json.Serialization;
+
+namespace Altinn.Studio.Designer.Models.Dto;
+
+public class Page
+{
+    [JsonPropertyName("id")]
+    public string id { get; set; }
+}

backend/src/Designer/Models/Dto/Pages.cs

@@ -0,0 +1,10 @@
+using System.Collections.Generic;
+using System.Text.Json.Serialization;
+
+namespace Altinn.Studio.Designer.Models.Dto;
+
+public class Pages
+{
+    [JsonPropertyName("pages")]
+    public List<Page> pages { get; set; }
+}

backend/src/Designer/Services/Implementation/LayoutService.cs

@@ -0,0 +1,85 @@
+using System.Linq;
+using System.Text.Json.Nodes;
+using System.Threading.Tasks;
+using Altinn.Studio.Designer.Infrastructure.GitRepository;
+using Altinn.Studio.Designer.Models;
+using Altinn.Studio.Designer.Models.Dto;
+using Altinn.Studio.Designer.Services.Interfaces;
+
+namespace Altinn.Studio.Designer.Services.Implementation
+{
+    public class LayoutService(IAltinnGitRepositoryFactory altinnGitRepositoryFactory) : ILayoutService
+    {
+        private static Pages getPagesFromSettings(JsonNode settings)
+        {
+            Pages pages = new()
+            {
+                pages = []
+            };
+
+            JsonNode pagesNode = settings["pages"];
+            JsonArray pagesArray = pagesNode["order"] as JsonArray;
+            foreach (JsonNode pageNode in pagesArray)
+            {
+                string pageId = pageNode.GetValue<string>();
+                pages.pages.Add(new Page { id = pageId });
+            }
+
+            return pages;
+        }
+
+        public async Task<Pages> getPagesByLayoutId(AltinnRepoEditingContext editingContext, string layoutSetId)
+        {
+            AltinnAppGitRepository appRepository = altinnGitRepositoryFactory.GetAltinnAppGitRepository(editingContext.Org, editingContext.Repo, editingContext.Developer);
+            JsonNode jsonNode = await appRepository.GetLayoutSettingsAndCreateNewIfNotFound(layoutSetId);
+            Pages pages = getPagesFromSettings(jsonNode);
+            return pages;
+        }
+
+        public async Task<Page> getPageById(AltinnRepoEditingContext editingContext, string layoutSetId, string pageId)
+        {
+            AltinnAppGitRepository appRepository = altinnGitRepositoryFactory.GetAltinnAppGitRepository(editingContext.Org, editingContext.Repo, editingContext.Developer);
+            JsonNode jsonNode = await appRepository.GetLayoutSettingsAndCreateNewIfNotFound(layoutSetId);
+            Pages pages = getPagesFromSettings(jsonNode);
+            return pages.pages.Find(page => page.id == pageId) ?? null;
+        }
+
+        public async Task createPage(AltinnRepoEditingContext editingContext, string layoutSetId, string pageId)
+        {
+            AltinnAppGitRepository appRepository = altinnGitRepositoryFactory.GetAltinnAppGitRepository(editingContext.Org, editingContext.Repo, editingContext.Developer);
+
+            await appRepository.CreatePageLayoutFile(layoutSetId, pageId);
+
+            JsonNode jsonNode = await appRepository.GetLayoutSettingsAndCreateNewIfNotFound(layoutSetId);
+            (jsonNode["pages"]["order"] as JsonArray).Add(pageId);
+            await appRepository.SaveLayoutSettings(layoutSetId, jsonNode);
+        }
+
+        public async Task deletePage(AltinnRepoEditingContext editingContext, string layoutSetId, string pageId)
+        {
+            AltinnAppGitRepository appRepository = altinnGitRepositoryFactory.GetAltinnAppGitRepository(editingContext.Org, editingContext.Repo, editingContext.Developer);
+
+            appRepository.DeleteLayout(layoutSetId, pageId);
+
+            JsonNode jsonNode = await appRepository.GetLayoutSettingsAndCreateNewIfNotFound(layoutSetId);
+            JsonArray orderArray = jsonNode["pages"]["order"] as JsonArray;
+            JsonNode orderPage = orderArray.First(node => node.GetValue<string>().Equals(pageId));
+            orderArray.Remove(orderPage);
+            await appRepository.SaveLayoutSettings(layoutSetId, jsonNode);
+        }
+
+        public async Task updatePage(AltinnRepoEditingContext editingContext, string layoutSetId, string pageId, Page page)
+        {
+            AltinnAppGitRepository appRepository = altinnGitRepositoryFactory.GetAltinnAppGitRepository(editingContext.Org, editingContext.Repo, editingContext.Developer);
+
+            appRepository.UpdateFormLayoutName(layoutSetId, pageId, page.id);
+
+            JsonNode jsonNode = await appRepository.GetLayoutSettingsAndCreateNewIfNotFound(layoutSetId);
+            JsonArray orderArray = jsonNode["pages"]["order"] as JsonArray;
+            JsonNode orderPage = orderArray.First(node => node.GetValue<string>().Equals(pageId));
+            int pageIndex = orderArray.IndexOf(orderPage);
+            orderArray[pageIndex] = page.id;
+            await appRepository.SaveLayoutSettings(layoutSetId, jsonNode);
+        }
+    }
+}

backend/src/Designer/Services/Interfaces/ILayoutService.cs

@@ -0,0 +1,17 @@
+
+using System.Threading.Tasks;
+using Altinn.Studio.Designer.Models;
+using Altinn.Studio.Designer.Models.Dto;
+
+namespace Altinn.Studio.Designer.Services.Interfaces
+{
+    public interface ILayoutService
+    {
+        public Task<Pages> getPagesByLayoutId(AltinnRepoEditingContext editingContext, string layoutSetId);
+        public Task<Page> getPageById(AltinnRepoEditingContext editingContext, string layoutSetId, string pageId);
+
+        public Task createPage(AltinnRepoEditingContext editingContext, string layoutSetId, string pageId);
+        public Task deletePage(AltinnRepoEditingContext editingContext, string layoutSetId, string pageId);
+        public Task updatePage(AltinnRepoEditingContext editingContext, string layoutSetId, string pageId, Page page);
+    }
+}