Enhance array properties with item type metadata and nested structures

src/lib/blueprint.ts

@@ -254,11 +254,66 @@ interface RecordProperty extends BaseProperty {
   jsonType: 'object'
 }
 
-interface ListProperty extends BaseProperty {
+interface BaseListProperty extends BaseProperty {
   format: 'list'
   jsonType: 'array'
+  itemFormat: string
 }
 
+interface StringListProperty extends BaseListProperty {
+  itemFormat: 'string'
+}
+
+interface NumberListProperty extends BaseListProperty {
+  itemFormat: 'number'
+}
+
+interface BooleanListProperty extends BaseListProperty {
+  itemFormat: 'boolean'
+}
+
+interface DatetimeListProperty extends BaseListProperty {
+  itemFormat: 'datetime'
+}
+
+interface IdListProperty extends BaseListProperty {
+  itemFormat: 'id'
+}
+
+interface EnumListProperty extends BaseListProperty {
+  itemFormat: 'enum'
+  itemEnumValues: EnumValue[]
+}
+
+interface ObjectListProperty extends BaseListProperty {
+  itemFormat: 'object'
+  itemProperties: Property[]
+}
+
+interface RecordListProperty extends BaseListProperty {
+  itemFormat: 'record'
+}
+
+interface DiscriminatedListProperty extends BaseListProperty {
+  itemFormat: 'discriminated_object'
+  discriminator: string
+  variants: Array<{
+    properties: Property[]
+    description: BaseProperty['description']
+  }>
+}
+
+type ListProperty =
+  | StringListProperty
+  | NumberListProperty
+  | BooleanListProperty
+  | DatetimeListProperty
+  | IdListProperty
+  | EnumListProperty
+  | ObjectListProperty
+  | RecordListProperty
+  | DiscriminatedListProperty
+
 interface BooleanProperty extends BaseProperty {
   format: 'boolean'
   jsonType: 'boolean'
@@ -1142,8 +1197,94 @@ const createProperty = (
       return { ...baseProperty, format: 'string', jsonType: 'string' }
     case 'boolean':
       return { ...baseProperty, format: 'boolean', jsonType: 'boolean' }
-    case 'array':
-      return { ...baseProperty, format: 'list', jsonType: 'array' }
+    case 'array': {
+      function createListProperty<T extends BaseListProperty>(
+        format: string,
+        extraProps = {},
+      ): T {
+        const baseListProps = {
+          ...baseProperty,
+          format: 'list' as const,
+          jsonType: 'array' as const,
+          itemFormat: format,
+          ...extraProps,
+        }
+
+        return baseListProps as T
+      }
+
+      const fallbackListProperty =
+        createListProperty<RecordListProperty>('record')
+
+      if (prop.items == null) {
+        return fallbackListProperty
+      }
+
+      if ('oneOf' in prop.items) {
+        if (!prop.items.oneOf.every((schema) => schema.type === 'object')) {
+          return fallbackListProperty
+        }
+
+        if (prop.items.discriminator?.propertyName == null) {
+          throw new Error(
+            `Missing discriminator property name for ${name} in ${parentPaths.join('.')}`,
+          )
+        }
+
+        return createListProperty<DiscriminatedListProperty>(
+          'discriminated_object',
+          {
+            discriminator: prop.items.discriminator.propertyName,
+            variants: prop.items.oneOf.map((schema) => ({
+              properties: createProperties(schema.properties ?? {}, [
+                ...parentPaths,
+                name,
+              ]),
+              description: schema.description ?? '',
+            })),
+          },
+        )
+      }
+
+      const itemProperty = createProperty('item', prop.items, [
+        ...parentPaths,
+        name,
+      ])
+
+      switch (itemProperty.format) {
+        case 'string':
+          return createListProperty<StringListProperty>('string')
+
+        case 'number':
+          return createListProperty<NumberListProperty>('number')
+
+        case 'boolean':
+          return createListProperty<BooleanListProperty>('boolean')
+
+        case 'datetime':
+          return createListProperty<DatetimeListProperty>('datetime')
+
+        case 'id':
+          return createListProperty<IdListProperty>('id')
+
+        case 'enum':
+          return createListProperty<EnumListProperty>('enum', {
+            itemEnumValues: itemProperty.values,
+          })
+
+        case 'object':
+          return createListProperty<ObjectListProperty>('object', {
+            itemProperties: itemProperty.properties,
+          })
+
+        case 'record':
+          return createListProperty<RecordListProperty>('record')
+
+        default:
+          return fallbackListProperty
+      }
+    }
+
     case 'object':
       if (prop.properties !== undefined) {
         return {

src/lib/openapi/types.ts

@@ -95,6 +95,9 @@ export interface OpenapiSchema {
   >
   oneOf?: OpenapiSchema[]
   allOf?: OpenapiSchema[]
+  discriminator?: {
+    propertyName: string
+  }
 }
 
 export interface OpenapiComponents {

test/snapshots/blueprint.test.ts.md

@@ -411,6 +411,7 @@ Generated by [AVA](https://avajs.dev).
               isDeprecated: false,
               isDraft: false,
               isUndocumented: false,
+              itemFormat: 'string',
               jsonType: 'array',
               name: 'array_prop',
               undocumentedMessage: '',
@@ -1618,6 +1619,7 @@ Generated by [AVA](https://avajs.dev).
               isDeprecated: false,
               isDraft: false,
               isUndocumented: false,
+              itemFormat: 'string',
               jsonType: 'array',
               name: 'array_prop',
               undocumentedMessage: '',