From f6e8100da143d522c90dc34fe0ae6c5107ad9c47 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E8=97=8D+85CD?= <50108258+kwaa@users.noreply.github.com>
Date: Tue, 26 Dec 2023 21:08:00 +0800
Subject: [PATCH] =?UTF-8?q?feat(remark-fff):=20=E2=9C=A8=20support=20neste?=
 =?UTF-8?q?d=20target?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .changeset/poor-glasses-deliver.md           |  9 +++
 packages/remark-fff/src/plugin.ts            | 64 ++++++++++++--------
 packages/remark-fff/src/types.ts             | 39 ++++--------
 packages/remark-fff/test/frontmatter.spec.ts | 23 +++++++
 4 files changed, 83 insertions(+), 52 deletions(-)
 create mode 100644 .changeset/poor-glasses-deliver.md

diff --git a/.changeset/poor-glasses-deliver.md b/.changeset/poor-glasses-deliver.md
new file mode 100644
index 0000000..7bf142c
--- /dev/null
+++ b/.changeset/poor-glasses-deliver.md
@@ -0,0 +1,9 @@
+---
+"remark-fff": patch
+"fff-flavored-frontmatter": patch
+"fff-transform-presets": patch
+"indiekit-preset-fff": patch
+"markdown-it-fff": patch
+---
+
+Version 1.2.0-alpha.1
diff --git a/packages/remark-fff/src/plugin.ts b/packages/remark-fff/src/plugin.ts
index b5b2e09..80b12f0 100644
--- a/packages/remark-fff/src/plugin.ts
+++ b/packages/remark-fff/src/plugin.ts
@@ -2,7 +2,7 @@ import type { Plugin, Transformer } from 'unified'
 
 import { strict, transform } from 'fff-flavored-frontmatter'
 
-import type { _Post, RemarkFFFOptions } from './types'
+import type { RemarkFFFOptions } from './types'
 
 /**
  * Remark plugin for auto-conversion other frontmatter variable formats to {@link https://fff.js.org | FFF Flavored Frontmatter}.
@@ -19,40 +19,52 @@ export const remarkFFF: Plugin<[RemarkFFFOptions]>
     },
   ): Transformer =>
     (_tree, file) => {
-    // make TS happy
-      const post: _Post = file as unknown as _Post
-      const fm = transform(
-        {
-          ...(options.target === 'mdsvex'
-            ? post.data.fm
-            : (options.target === 'astro'
-                ? post.data.astro.frontmatter
-                // eslint-disable-next-line unicorn/no-nested-ternary
-                : (options.target === 'nuxt'
-                    ? post.data
-                    : post.data))),
-        },
-        [
-          ...options.presets,
-          ...(options.strict ? [strict(options.strict)] : []),
-        ],
-      )
+      let targets: string[] | undefined
+
+      // Compatible with old target parameters before 1.2.
+      // TODO: remove in 1.3
       switch (options.target) {
         case 'mdsvex': {
-          file.data.fm = fm
+          targets = ['fm']
           break
         }
         case 'astro': {
-          file.data.astro = {
-            ...file.data.astro as object,
-            frontmatter: fm,
-          }
+          targets = ['astro', 'frontmatter']
           break
         }
         case 'nuxt': {
-          file.data = fm
+          targets = undefined
           break
         }
-        default: { file.data = fm }
+        default: {
+          targets = options.target
+        }
       }
+
+      let input = file.data as Record<string, unknown>
+      if (targets) {
+        for (const target of targets) {
+          try {
+            input = input[target] as Record<string, unknown>
+          }
+          catch {
+            input = {}
+          }
+        }
+      }
+
+      const output = transform(
+        input,
+        [
+          ...options.presets,
+          ...(options.strict ? [strict(options.strict)] : []),
+        ],
+      )
+
+      file.data = targets
+        ? {
+            ...file.data,
+            ...targets.reduceRight((output, key) => ({ [key]: output }), output),
+          }
+        : output
     }
diff --git a/packages/remark-fff/src/types.ts b/packages/remark-fff/src/types.ts
index 42f9174..1c844a5 100644
--- a/packages/remark-fff/src/types.ts
+++ b/packages/remark-fff/src/types.ts
@@ -1,5 +1,4 @@
 import type {
-  FFFFlavoredFrontmatter,
   FFFTransformPreset,
   StrictPresetOptions,
 } from 'fff-flavored-frontmatter'
@@ -11,30 +10,18 @@ import type {
 export interface RemarkFFFOptions {
   presets: FFFTransformPreset[]
   strict?: StrictPresetOptions
+  /**
+   * Replacement target for Remark FFF.
+   * @example
+   * ```ts
+   * // astro: file.data.astro.frontmatter
+   * const target = ['astro', 'frontmatter'] // file.data['astro']['frontmatter']
+   * // mdsvex: file.data.fm
+   * const target = ['fm'] // file.data['fm']
+   * // nuxt: file.data
+   * const target = undefined // file.data
+   * ```
+   */
   // eslint-disable-next-line @typescript-eslint/ban-types
-  target: 'astro' | 'mdsvex' | 'nuxt' | (string & {})
+  target?: 'astro' | 'mdsvex' | 'nuxt' | string[]
 }
-
-/**
- * Internal Post Data Type.
- * @internal
- */
-export type _Post =
-  | /** MDsveX */ {
-      data: {
-        astro: {
-          frontmatter: FFFFlavoredFrontmatter & Record<string, unknown>
-        }
-        fm: never
-      }
-      filename: never
-      path: string
-    }
-  | /** Astro */ {
-      data: {
-        astro: never
-        fm: FFFFlavoredFrontmatter & Record<string, unknown>
-      }
-      filename: string
-      path: never
-    }
diff --git a/packages/remark-fff/test/frontmatter.spec.ts b/packages/remark-fff/test/frontmatter.spec.ts
index 7936f67..95b8e7c 100644
--- a/packages/remark-fff/test/frontmatter.spec.ts
+++ b/packages/remark-fff/test/frontmatter.spec.ts
@@ -131,4 +131,27 @@ describe('remark-fff strict mode', () => {
       .processSync(file).data as { fm: FFFFlavoredFrontmatter }
     expect(fm.image).toEqual('https://fff.js.org/glowing_star.svg')
   })
+  it('custom nested target', () => {
+    const file = new VFile({
+      data: {
+        a: {
+          b: {
+            c: {
+              d: {
+                date: '2023-12-25',
+              },
+            },
+          },
+        },
+      },
+    })
+    const data = remark()
+      .use(remarkFrontmatter)
+      .use(remarkFFF, {
+        presets: [{ created: 'date' }],
+        target: ['a', 'b', 'c', 'd'],
+      })
+      .processSync(file).data as { a: { b: { c: { d: FFFFlavoredFrontmatter } } } }
+    expect(data.a.b.c.d.created).toEqual('2023-12-25')
+  })
 })