Persist session color to transcript for resume support

Patch saveAgentColor to expose it via globalThis, then call it
from the INJECTION via queueMicrotask so the env-based color
is written to the session transcript. On resume,
computeStandaloneAgentContext reads agentColor from the log
and restores the prompt bar color automatically.

Author: VitalyOstanin

src/patches/sessionColor.test.ts

@@ -1,5 +1,10 @@
 import { describe, it, expect } from 'vitest';
-import { writeSessionColor } from './sessionColor';
+import { writeSessionColor, patchSaveAgentColor } from './sessionColor';
+
+const makeSaveAgentColor = () =>
+  ';async function Mr$(H,$,q){let K=q??sT(H);' +
+  'if(Hv(K,{type:"agent-color",agentColor:$,sessionId:H}),H===V$())' +
+  'WA().currentSessionAgentColor=$;c("tengu_agent_color_set",{})}';
 
 const makeCLIState = () =>
   'effortValue:oR(w.effort),' +
@@ -12,37 +17,41 @@ const makeDefaultState = () =>
 const makeBoth = () =>
   'first{' + makeDefaultState() + 'second{' + makeCLIState();
 
+const makeFullFile = () => makeBoth() + makeSaveAgentColor();
+
 describe('sessionColor', () => {
   describe('writeSessionColor', () => {
-    it('should inject into CLI initialState', () => {
-      const result = writeSessionColor(makeCLIState());
+    it('should inject into CLI initialState and patch saveAgentColor', () => {
+      const result = writeSessionColor(makeFullFile());
       expect(result).not.toBeNull();
       expect(result).toContain('TWEAKCC_SESSION_COLOR');
       expect(result).toContain('{name:"",color:__c}');
+      expect(result).toContain('__tweakccSaveAgentColor');
     });
 
     it('should inject into default app state', () => {
-      const result = writeSessionColor(makeDefaultState());
+      const input = makeDefaultState() + makeSaveAgentColor();
+      const result = writeSessionColor(input);
       expect(result).not.toBeNull();
       expect(result).toContain('TWEAKCC_SESSION_COLOR');
     });
 
-    it('should patch both locations when both present', () => {
-      const result = writeSessionColor(makeBoth())!;
+    it('should patch both initialState locations', () => {
+      const result = writeSessionColor(makeFullFile())!;
       expect(result).not.toBeNull();
       const count = (result.match(/TWEAKCC_SESSION_COLOR/g) || []).length;
       expect(count).toBe(2);
     });
 
     it('should validate color against allowed list', () => {
-      const result = writeSessionColor(makeCLIState())!;
+      const result = writeSessionColor(makeFullFile())!;
       expect(result).toContain('.includes(__c)');
       expect(result).toContain('"green"');
       expect(result).toContain('"cyan"');
     });
 
     it('should be idempotent', () => {
-      const first = writeSessionColor(makeBoth())!;
+      const first = writeSessionColor(makeFullFile())!;
       const second = writeSessionColor(first)!;
       expect(second).toBe(first);
     });
@@ -51,5 +60,37 @@ describe('sessionColor', () => {
       const result = writeSessionColor('not a valid file');
       expect(result).toBeNull();
     });
+
+    it('should schedule color save via queueMicrotask', () => {
+      const result = writeSessionColor(makeFullFile())!;
+      expect(result).toContain('queueMicrotask');
+      expect(result).toContain('__tweakccSaveAgentColor');
+    });
+
+    it('should expose saveAgentColor on globalThis', () => {
+      const result = writeSessionColor(makeFullFile())!;
+      expect(result).toContain(
+        'globalThis.__tweakccSaveAgentColor=(c)=>Mr$(V$(),c)'
+      );
+    });
+  });
+
+  describe('patchSaveAgentColor', () => {
+    it('should find and patch saveAgentColor', () => {
+      const result = patchSaveAgentColor(makeSaveAgentColor());
+      expect(result).not.toBeNull();
+      expect(result).toContain('globalThis.__tweakccSaveAgentColor');
+    });
+
+    it('should return null when pattern not found', () => {
+      const result = patchSaveAgentColor('no match here');
+      expect(result).toBeNull();
+    });
+
+    it('should preserve original function', () => {
+      const result = patchSaveAgentColor(makeSaveAgentColor())!;
+      expect(result).toContain('async function Mr$');
+      expect(result).toContain('type:"agent-color"');
+    });
   });
 });

src/patches/sessionColor.ts

@@ -16,9 +16,11 @@ const INJECTION =
   `,standaloneAgentContext:` +
   `(()=>{` +
   `let __c=process.env.TWEAKCC_SESSION_COLOR;` +
-  `return __c&&${JSON.stringify(VALID_COLORS)}.includes(__c)` +
-  `?{name:"",color:__c}` +
-  `:void 0` +
+  `if(!__c||!${JSON.stringify(VALID_COLORS)}.includes(__c))return void 0;` +
+  `queueMicrotask(()=>{` +
+  `if(globalThis.__tweakccSaveAgentColor)globalThis.__tweakccSaveAgentColor(__c)` +
+  `});` +
+  `return{name:"",color:__c}` +
   `})()`;
 
 export const writeSessionColor = (oldFile: string): string | null => {
@@ -64,5 +66,52 @@ export const writeSessionColor = (oldFile: string): string | null => {
     return null;
   }
 
+  const saveColorResult = patchSaveAgentColor(result);
+  if (!saveColorResult) {
+    debug('patch: sessionColor: failed to patch saveAgentColor');
+    return null;
+  }
+
+  return saveColorResult;
+};
+
+export const patchSaveAgentColor = (oldFile: string): string | null => {
+  const pattern = new RegExp(
+    '([,;{}])' +
+      '(async function ([$\\w]+)' +
+      '\\(([$\\w]+),([$\\w]+),([$\\w]+)\\)' +
+      '\\{let [$\\w]+=\\6\\?\\?[$\\w]+\\(\\4\\);' +
+      'if\\([$\\w]+\\([$\\w]+,' +
+      '\\{type:"agent-color",agentColor:\\5,sessionId:\\4\\}\\),' +
+      '\\4===([$\\w]+)\\(\\)\\))'
+  );
+  const match = oldFile.match(pattern);
+  if (!match || match.index === undefined) {
+    return null;
+  }
+
+  const delimiter = match[1];
+  const funcBody = match[2];
+  const funcName = match[3];
+  const getSessionIdName = match[7];
+
+  const replacement =
+    `${delimiter}globalThis.__tweakccSaveAgentColor=` +
+    `(c)=>${funcName}(${getSessionIdName}(),c);` +
+    funcBody;
+
+  const result =
+    oldFile.slice(0, match.index) +
+    replacement +
+    oldFile.slice(match.index + match[0].length);
+
+  showDiff(
+    oldFile,
+    result,
+    replacement,
+    match.index,
+    match.index + match[0].length
+  );
+
   return result;
 };