Add ability to retrieve specific page versions and nodes with ?version=XX param

app/models/VersionedModel.js

@@ -11,6 +11,28 @@ class VersionedModel extends Model {
         }
     }
 
+    __is_version_instantation = false
+    __version_base = undefined
+    __version_data = undefined
+
+    is_a_version() {
+        return this.__is_version_instantation
+    }
+
+    version_base() {
+        return this.__version_base
+    }
+
+    raw_version_data() {
+        return this.__version_data
+    }
+
+    __initialize_version(base, data = {}) {
+        this.__is_version_instantation = true
+        this.__version_base = base
+        this.__version_data = data
+    }
+
     async version_save(message = undefined, user_id = undefined) {
         await this.new_version(message, user_id)
         return this.save()
@@ -44,6 +66,43 @@ class VersionedModel extends Model {
         delete data.version_archive
         return data
     }
+
+    async get_version_data(version_num = undefined) {
+        if ( typeof version_num === 'undefined' ) {
+            return await this.cast_to_version_data()
+        } else {
+            return this.version_archive.find(data => Number(data.version_num) === Number(version_num))
+        }
+    }
+
+    has_version(version_num = undefined) {
+        return !!this.version_archive.find(data => {
+            return Number(data.version_num) === Number(version_num)
+        })
+    }
+
+    toJSON() {
+        const data = {...this}
+        delete data.__version_data
+        delete data.__version_base
+        delete data.__is_version_instantation
+        delete data.version_archive
+
+        if ( this.is_a_version() ) {
+            data.version_message = this.__version_data.version_message
+            data.version_user_id = this.__version_data.version_user_id
+        }
+
+        return data
+    }
+
+    async as_version(version_num = undefined) {
+        const data = await this.get_version_data(version_num)
+        console.log('as version data', data, version_num)
+        const inst = new this.constructor(data)
+        inst.__initialize_version(this, data)
+        return inst
+    }
 }
 
 module.exports = exports = VersionedModel

app/models/api/Page.model.js

@@ -115,8 +115,35 @@ class Page extends VersionedModel {
 
 	get nodes() {
 		const Node = this.models.get("api:Node")
-		return this.has_many(Node, "NodeIds", "UUID")
+		const node_promise = this.has_many(Node, "NodeIds", "UUID")
+		if ( this.is_a_version() ) {
+			// return the nodes for this version!
+			return (async () => {
+				const nodes = await node_promise
+				const version_data = this.raw_version_data()
+				const return_nodes = []
+				if ( version_data?.node_version_nums ) {
+					const node_x_version_num = {}
+					for ( const item of version_data.node_version_nums ) {
+						node_x_version_num[item.NodeId] = item.version_num
+					}
+
+					for ( const node of nodes ) {
+						if ( node_x_version_num[node.UUID] ) {
+							return_nodes.push(await node.as_version(node_x_version_num[node.UUID]))
+						} else {
+							return_nodes.push(node)
+						}
+					}
+				}
+
+				return return_nodes
+			})()
+		} else {
+			return node_promise
+		}
 	}
+
 	get childPages() {
 		const Page = this.models.get("api:Page")
 		return this.has_many(Page, "ChildPageIds", "UUID")