cateditor store: ensure a skeleton catalog to simplify code

cateditor/src/pages/editor/store/index.js

@@ -6,9 +6,13 @@ import { paginateModels, sectionTitle, extendModelFromMaterial } from '@/paginat
 
 Vue.use(Vuex)
 
+function skeletonCatalog() {
+  return { sections: [] }
+}
+
 export const store = new Vuex.Store({
   state: {
-    catalog: null,
+    catalog: skeletonCatalog(),
     materials: {},
     selectedSectionID: null,
     selectedModelID: null,
@@ -26,39 +30,23 @@ export const store = new Vuex.Store({
     },
 
     sections: state => {
-      if (state.catalog != null) {
       return state.catalog.sections
-      } else {
-        return null
-      }
     },
 
     section: state => id => {
-      if (state.catalog && id) {
       return state.catalog.sections.find(s => s.id === id)
-      } else {
-        return null
-      }
     },
 
     nextSectionID: state => {
-      if (state.catalog != null) {
       let id = 0
       for (let section of state.catalog.sections) {
         id = Math.max(id, section.id)
       }
       return id + 1
-      } else {
-        return -1
-      }
     },
 
     selectedSection: (state, getters) => {
-      if (state.catalog && state.selectedSectionID) {
       return getters.section(state.selectedSectionID)
-      } else {
-        return null
-      }
     },
 
     selectedModel: (state, getters) => {
@@ -104,20 +92,8 @@ export const store = new Vuex.Store({
       return getters.material(state.selectedMaterialID)
     },
 
-    catalogSections: state => {
-      if (state.catalog != null) {
-        return state.catalog.sections
-      } else {
-        return null
-      }
-    },
-
     catalogProperty: state => key => {
-      if (state.catalog != null) {
       return state.catalog[key]
-      } else {
-        return null
-      }
     },
 
     //
@@ -212,7 +188,11 @@ export const store = new Vuex.Store({
     },
 
     setCatalog(state, cat) {
+      if (cat !== null) {
         state.catalog = cat
+      } else {
+        state.catalog = skeletonCatalog()
+      }
     },
 
     setLoadingCatalog(state, value) {
@@ -228,10 +208,7 @@ export const store = new Vuex.Store({
     },
 
     setCatalogProperty(state, { key, value }) {
-      console.log('mutation set prop', key, value)
-      if (state.catalog) {
       state.catalog[key] = value
-      }
     },
 
   },
@@ -350,11 +327,6 @@ export const store = new Vuex.Store({
     },
 
     addMaterialToCatalog({ commit, getters, state }, material) {
-      if (!state.catalog) {
-        console.log('no catalog to add materials to')
-        return
-      }
-
       // ensure material, not just id
       if (typeof material === 'string' || typeof material === 'number') {
         material = getters.material(material)
@@ -432,7 +404,7 @@ export const store = new Vuex.Store({
     },
 
     newCatalog({ commit }) {
-      commit('setCatalog', {})
+      commit('setCatalog', skeletonCatalog())
     },
 
     async fetchProducts({ commit, dispatch }, text) {
@@ -478,13 +450,13 @@ export const store = new Vuex.Store({
           commit('setCatalog', response.data.catalog)
         } else {
           console.log('no catalog')
-          commit('setCatalog', null)
+          commit('newCatalog')
         }
         commit('setLoadingCatalog', false)
       } catch (error) {
         // TODO set loading error property
         console.error('error loading catalog: ', error)
-        commit('setCatalog', null)
+        commit('newCatalog')
         commit('setLoadingCatalog', false)
       }
     },
@@ -500,7 +472,7 @@ export const store = new Vuex.Store({
             commit('setCatalog', response.data)
           } else {
             console.error('no catalog returned from save!')
-            commit('setCatalog', null)
+            commit('newCatalog')
           }
           commit('setSavingCatalog', false)
         })