From 71d53095fbe46b594d51ab906d690a3227b47371 Mon Sep 17 00:00:00 2001
From: cha0s <git@cha0s.io>
Date: Fri, 8 Apr 2022 17:15:23 -0500
Subject: [PATCH] feat: undo/redo

---
 build/flecks.yml                              |  2 +-
 packages/core/src/index.js                    | 32 +++++++++----
 .../src/server/packets/decorators/action.js   | 45 ++++++++++++++++++-
 packages/core/src/server/start-flush.js       | 16 ++++---
 4 files changed, 77 insertions(+), 18 deletions(-)

diff --git a/build/flecks.yml b/build/flecks.yml
index 7c3e78e..e6cf9d0 100644
--- a/build/flecks.yml
+++ b/build/flecks.yml
@@ -51,8 +51,8 @@
     show: false
   quitOnClosed: false
   window:
-    - '@persea/core'
     - '...'
+    - '@persea/core'
 '@flecks/governor': {}
 '@flecks/react':
   providers:
diff --git a/packages/core/src/index.js b/packages/core/src/index.js
index daa1e5a..8a2fda6 100644
--- a/packages/core/src/index.js
+++ b/packages/core/src/index.js
@@ -1,4 +1,9 @@
-import {patchJsonResource, replaceResource} from '@avocado/resource/persea';
+import {
+  patchJsonResource,
+  redo,
+  replaceResource,
+  undo,
+} from '@avocado/resource/persea';
 import {Hooks} from '@flecks/core';
 
 import Persea from './components/persea';
@@ -17,14 +22,23 @@ export default {
     '@flecks/react.roots': () => Persea,
     '@flecks/redux.effects': (flecks) => {
       const withSocket = (fn) => (...args) => fn(...args.concat(flecks.get('$flecks/socket.socket')));
-      return {
-        [patchJsonResource]: withSocket((store, action, socket) => {
-          socket.send(['Action', action]);
-        }),
-        [replaceResource]: withSocket((store, action, socket) => {
-          socket.send(['Action', action]);
-        }),
-      };
+      return Object.fromEntries(
+        [
+          patchJsonResource,
+          redo,
+          replaceResource,
+          undo,
+        ]
+          .map((action) => [
+            action,
+            withSocket((store, action, socket) => {
+              if (action.meta?.isRemote) {
+                return;
+              }
+              socket.send(['Action', action]);
+            }),
+          ]),
+      );
     },
     '@flecks/redux.slices': () => ({
       project,
diff --git a/packages/core/src/server/packets/decorators/action.js b/packages/core/src/server/packets/decorators/action.js
index 26708a4..56a017d 100644
--- a/packages/core/src/server/packets/decorators/action.js
+++ b/packages/core/src/server/packets/decorators/action.js
@@ -1,4 +1,13 @@
-import {patchJsonResource, replaceResource} from '@avocado/resource/persea';
+import {readFile, writeFile} from 'fs/promises';
+import {join} from 'path';
+
+import {
+  patchJsonResource,
+  redo,
+  replaceResource,
+  undo,
+} from '@avocado/resource/persea';
+import {applyPatch, compare} from 'fast-json-patch';
 
 export default (Action, flecks) => class ProjectAction extends Action {
 
@@ -9,10 +18,44 @@ export default (Action, flecks) => class ProjectAction extends Action {
         flecks.get('$persea/core.patches').push(payload);
         break;
       }
+      case redo.toString(): {
+        const {project, uri} = payload;
+        const path = join(process.cwd(), 'projects', project, uri);
+        const {toBuffer, fromBuffer} = flecks.get('$avocado/resource/persea.controllers')
+          .find(({matcher}) => uri.match(matcher));
+        const buffer = await readFile(path);
+        const json = fromBuffer(buffer, flecks);
+        if (json.history?.redo?.length) {
+          const patch = json.history.redo[json.history.redo.length - 1];
+          socket.send(['Action', patchJsonResource({patch, project, uri}, true)]);
+          applyPatch(json, patch);
+          json.history.undo.push(compare(json, fromBuffer(buffer, flecks)));
+          json.history.redo.pop();
+          await writeFile(path, toBuffer(json, flecks));
+        }
+        break;
+      }
       case replaceResource.toString(): {
         flecks.get('$persea/core.replacements').push(payload);
         break;
       }
+      case undo.toString(): {
+        const {project, uri} = payload;
+        const path = join(process.cwd(), 'projects', project, uri);
+        const {toBuffer, fromBuffer} = flecks.get('$avocado/resource/persea.controllers')
+          .find(({matcher}) => uri.match(matcher));
+        const buffer = await readFile(path);
+        const json = fromBuffer(buffer, flecks);
+        if (json.history?.undo?.length) {
+          const patch = json.history.undo[json.history.undo.length - 1];
+          socket.send(['Action', patchJsonResource({patch, project, uri}, true)]);
+          applyPatch(json, patch);
+          json.history.redo.push(compare(json, fromBuffer(buffer, flecks)));
+          json.history.undo.pop();
+          await writeFile(path, toBuffer(json, flecks));
+        }
+        break;
+      }
       default:
     }
     return super.respond(packet, socket);
diff --git a/packages/core/src/server/start-flush.js b/packages/core/src/server/start-flush.js
index 75f2e24..528beda 100644
--- a/packages/core/src/server/start-flush.js
+++ b/packages/core/src/server/start-flush.js
@@ -1,11 +1,7 @@
-import fs from 'fs';
+import {readFile, writeFile} from 'fs/promises';
 import {join} from 'path';
-import {promisify} from 'util';
 
-import {applyPatch} from 'fast-json-patch';
-
-const readFile = promisify(fs.readFile);
-const writeFile = promisify(fs.writeFile);
+import {applyPatch, compare} from 'fast-json-patch';
 
 const startFlush = (flecks) => {
   const flushPatches = async () => {
@@ -21,6 +17,7 @@ const startFlush = (flecks) => {
           patching[path] = new Promise((resolve) => {
             readFile(path).then((buffer) => {
               resolve({
+                fromBuffer,
                 toBuffer,
                 json: fromBuffer(buffer, flecks),
               });
@@ -34,7 +31,12 @@ const startFlush = (flecks) => {
       await Promise.all(
         Object.entries(patching)
           .map(async ([path, promise]) => {
-            const {toBuffer, json} = await promise;
+            const {fromBuffer, toBuffer, json} = await promise;
+            const buffer = await readFile(path);
+            const undo = compare(json, fromBuffer(buffer, flecks));
+            json.history = json.history || {redo: [], undo: []};
+            json.history.redo = [];
+            json.history.undo.push(undo);
             return writeFile(path, toBuffer(json, flecks));
           }),
       );