From e22fc330c85414c0881613894f1eb4194d37c67e Mon Sep 17 00:00:00 2001
From: purocean <purocean@gmail.com>
Date: Sat, 13 Nov 2021 10:31:52 +0800
Subject: [PATCH] feat(macro): add `$include` to include other document
 fragments

---
 src/renderer/plugins/markdown-macro.ts | 99 +++++++++++++++++++-------
 1 file changed, 74 insertions(+), 25 deletions(-)

diff --git a/src/renderer/plugins/markdown-macro.ts b/src/renderer/plugins/markdown-macro.ts
index 9678cbe3..cb490f23 100644
--- a/src/renderer/plugins/markdown-macro.ts
+++ b/src/renderer/plugins/markdown-macro.ts
@@ -1,40 +1,44 @@
+import frontMatter from 'front-matter'
 import type { Plugin } from '@fe/context'
 import { render } from '@fe/services/view'
+import { readFile } from '@fe/support/api'
+import type { Doc } from '@fe/types'
 import { getLogger, md5 } from '@fe/utils'
+import { dirname, resolve } from '@fe/utils/path'
 
-const logger = getLogger('macro')
+type Result = { __macroResult: true, vars?: Record<string, any>, toString: () => string }
+type Expression = { id: string, match: string, exp: string, vars: Record<string, any> }
+
+const logger = getLogger('plugin-macro')
 
 const AsyncFunction = Object.getPrototypeOf(async () => 0).constructor
-let macroCache: Record<string, Record<string, string>> = {}
+let macroCache: Record<string, Record<string, Result>> = {}
 
 function checkMacroResult (result: any) {
-  if (typeof result === 'object' ||
+  if (
+    result === null ||
     typeof result === 'function' ||
     typeof result === 'symbol' ||
-    typeof result === 'undefined'
+    typeof result === 'undefined' ||
+    (typeof result === 'object' && (!result.__macroResult))
   ) {
     throw new Error('Macro result type error.')
   }
 }
 
-function macro (match: string, vars: Record<string, any>, cache: Record<string, string>) {
-  const expression = match
-    .substring(2, match.length - 2)
-    .trim()
-    .replace(/(?:=\\>|<\\=)/g, x => x.replace('\\', ''))
+function macro (expression: Expression, cache: Record<string, Result>): Result {
+  logger.debug('macro', expression)
 
-  const id = md5(expression)
-
-  logger.debug(id, expression, vars)
+  const { id, match, exp, vars } = expression
 
   // async expression result cache
   if (id in cache) {
     return cache[id]
   }
 
-  const FunctionConstructor = expression.startsWith('await') ? AsyncFunction : Function
+  const FunctionConstructor = exp.startsWith('await') ? AsyncFunction : Function
 
-  const fun = new FunctionConstructor('vars', `with (vars) { return ${expression}; }`)
+  const fun = new FunctionConstructor('vars', `with (vars) { return ${exp}; }`)
 
   const result = fun(vars)
 
@@ -43,20 +47,20 @@ function macro (match: string, vars: Record<string, any>, cache: Record<string,
       checkMacroResult(res)
       return res
     }).catch(e => {
-      logger.error(id, e)
+      logger.error('macro', id, e)
       return match
     }).then(res => {
       cache[id] = res
-      logger.debug('async', id, 'rerender')
+      logger.debug('macro', 'async', id, 'rerender')
       render()
     })
 
-    return 'macro is running……'
+    return { __macroResult: true, toString: () => 'macro is running……' }
   }
 
   checkMacroResult(result)
 
-  return '' + result
+  return result
 }
 
 function lineCount (str: string) {
@@ -72,9 +76,36 @@ function lineCount (str: string) {
   return s
 }
 
+async function include (belongDoc: Doc | undefined | null, path: string): Promise<Result> {
+  if (!belongDoc) {
+    throw new Error('Current document is null')
+  }
+
+  try {
+    const absolutePath = resolve(dirname(belongDoc.path), path)
+    const { content } = await readFile({ repo: belongDoc.repo, path: absolutePath })
+    const fm = frontMatter(content)
+
+    // merge front-matter attributes to current document vars.
+    const vars = {}
+    if (fm.attributes && typeof fm.attributes === 'object') {
+      Object.assign(vars, fm.attributes)
+    }
+
+    return { __macroResult: true, vars, toString: () => fm.body }
+  } catch (error: any) {
+    return error.message
+  }
+}
+
 export default {
   name: 'markdown-macro',
   register: ctx => {
+    // clear cache after view refresh
+    ctx.registerHook('VIEW_BEFORE_REFRESH', () => {
+      macroCache = {}
+    })
+
     ctx.markdown.registerPlugin(md => {
       md.core.ruler.after('normalize', 'macro', (state) => {
         const env = state.env || {}
@@ -84,13 +115,14 @@ export default {
         }
 
         const file = env.file || {}
-        const vars = {
+        const vars: Record<string, any> = {
+          $include: include.bind(null, file),
           $ctx: ctx,
           $doc: {
             basename: file.name ? file.name.substring(0, file.name.lastIndexOf('.')) : '',
             ...ctx.lib.lodash.pick(env.file, 'name', 'repo', 'path', 'content', 'status')
           },
-          ...env.attributes
+          ...env.attributes,
         }
 
         if (!env.macroLines) {
@@ -106,14 +138,31 @@ export default {
         let posOffset = 0
         state.src = state.src.replace(reg, (match, matchPos) => {
           try {
-            const result = macro(match, vars, macroCache[cacheKey])
+            console.log('xxx', match, { ...vars })
+
+            const exp = match
+              .substring(2, match.length - 2)
+              .trim()
+              .replace(/(?:=\\>|<\\=)/g, x => x.replace('\\', ''))
+
+            const id = md5(exp)
+
+            const expression = { id, match, exp, vars }
+            const result = macro(expression, macroCache[cacheKey])
+
+            if (result && result.__macroResult && result.vars) {
+              Object.assign(vars, result.vars)
+            }
+
+            // result maybe string or other type.
+            const resultStr = '' + result
 
             const matchLine = lineCount(match)
-            const resultLine = lineCount(result)
+            const resultLine = lineCount(resultStr)
 
             if (resultLine !== matchLine) {
               const currentLineOffset = (matchLine - resultLine)
-              const currentPosOffset = (match.length - result.length)
+              const currentPosOffset = (match.length - resultStr.length)
               lineOffset += currentLineOffset
               posOffset += currentPosOffset
               env.macroLines.push({
@@ -125,11 +174,11 @@ export default {
                 currentPosOffset,
                 currentLineOffset,
                 matchLength: match.length,
-                resultLength: result.length,
+                resultLength: resultStr.length,
               })
             }
 
-            return result
+            return resultStr
           } catch (error) {}
 
           return match