feat(API): [PF-3167] Add component-index.json API endpoint for MCP

src/pages/api/component-index.json.ts

@@ -0,0 +1,119 @@
+import type { APIRoute } from 'astro'
+import { getApiIndex } from '../../utils/apiIndex/get'
+import { removeSubsection } from '../../utils/case'
+import { getOutputDir } from '../../utils/getOutputDir'
+import { join } from 'path'
+import { readFile } from 'fs/promises'
+
+export const prerender = true
+
+interface ComponentEntry {
+  section: string
+  page: string
+  tabs: string[]
+  hasProps: boolean
+  hasCss: boolean
+  exampleCount: number
+}
+
+export interface ComponentIndex {
+  version: string
+  components: Record<string, ComponentEntry>
+}
+
+// "about-modal" → "AboutModal", "forms_checkbox" → "Checkbox"
+function pageToPascalCase(page: string): string {
+  return removeSubsection(page)
+    .split('-')
+    .map((word) => word.charAt(0).toUpperCase() + word.slice(1))
+    .join('')
+}
+
+export const GET: APIRoute = async () => {
+  try {
+    const index = await getApiIndex()
+
+    // props.json keys include both component names ("Alert") and their prop
+    // interfaces ("AlertProps"). Filter out the interface entries to get the
+    // set of component names that have prop documentation available.
+    let componentNamesWithProps = new Set<string>()
+    try {
+      const outputDir = await getOutputDir()
+      const propsFile = await readFile(join(outputDir, 'props.json'), 'utf-8')
+      const propsData = JSON.parse(propsFile)
+      const propsSuffixPattern = /Props/i
+      componentNamesWithProps = new Set(
+        Object.keys(propsData).filter((name) => !propsSuffixPattern.test(name)),
+      )
+    } catch (error) {
+      if ((error as NodeJS.ErrnoException).code !== 'ENOENT') {
+        throw error
+      }
+    }
+
+    if (index.versions.length === 0) {
+      throw new Error('API index contains no versions')
+    }
+
+    // Latest version is last in sorted array (e.g., ["v5", "v6"] → "v6")
+    const version = index.versions[index.versions.length - 1]
+    const sections = index.sections[version] || []
+
+    const components: Record<string, ComponentEntry> = {}
+
+    for (const section of sections) {
+      const pagesKey = `${version}::${section}`
+      const pages = index.pages[pagesKey] || []
+
+      for (const page of pages) {
+        const tabsKey = `${version}::${section}::${page}`
+        const tabs = index.tabs[tabsKey] || []
+
+        let exampleCount = 0
+        for (const tab of tabs) {
+          const examplesKey = `${tabsKey}::${tab}`
+          const examples = index.examples[examplesKey] || []
+          exampleCount += examples.length
+        }
+
+        const hasCss = tabsKey in index.css && index.css[tabsKey].length > 0
+
+        const pascalName = pageToPascalCase(page)
+        const hasProps = componentNamesWithProps.has(pascalName)
+
+        // Prefer the first occurrence when multiple sections produce the same
+        // PascalCase key (e.g., components/table vs extensions/data-view_table)
+        if (!components[pascalName]) {
+          components[pascalName] = {
+            section,
+            page,
+            tabs,
+            hasProps,
+            hasCss,
+            exampleCount,
+          }
+        }
+      }
+    }
+
+    const componentIndex: ComponentIndex = { version, components }
+
+    return new Response(JSON.stringify(componentIndex), {
+      status: 200,
+      headers: {
+        'Content-Type': 'application/json',
+      },
+    })
+  } catch (error) {
+    return new Response(
+      JSON.stringify({
+        error: 'Failed to generate component index',
+        details: error instanceof Error ? error.message : String(error),
+      }),
+      {
+        status: 500,
+        headers: { 'Content-Type': 'application/json' },
+      },
+    )
+  }
+}