persist prompt drafts per session

src/components/prompt-input.tsx

@@ -2,13 +2,12 @@ import { createSignal, Show, onMount, For, onCleanup, createEffect, on, untrack
 import UnifiedPicker from "./unified-picker"
 import { addToHistory, getHistory } from "../stores/message-history"
 import { getAttachments, addAttachment, clearAttachments, removeAttachment } from "../stores/attachments"
-import { getPromptValue, setPromptValue, clearPromptValue } from "../stores/prompt-state"
 import { createFileAttachment, createTextAttachment, createAgentAttachment } from "../types/attachment"
 import type { Attachment } from "../types/attachment"
 import Kbd from "./kbd"
 import HintRow from "./hint-row"
 import { getActiveInstance } from "../stores/instances"
-import { agents } from "../stores/sessions"
+import { agents, getSessionDraftPrompt, setSessionDraftPrompt, clearSessionDraftPrompt } from "../stores/sessions"
 
 interface PromptInputProps {
   instanceId: string
@@ -57,11 +56,11 @@ export default function PromptInput(props: PromptInputProps) {
 
   const setPrompt = (value: string) => {
     setPromptInternal(value)
-    setPromptValue(props.instanceId, props.sessionId, value)
+    setSessionDraftPrompt(props.instanceId, props.sessionId, value)
   }
 
   const clearPrompt = () => {
-    clearPromptValue(props.instanceId, props.sessionId)
+    clearSessionDraftPrompt(props.instanceId, props.sessionId)
     setPromptInternal("")
   }
 
@@ -116,14 +115,14 @@ export default function PromptInput(props: PromptInputProps) {
         const sessionId = props.sessionId
 
         onCleanup(() => {
-          setPromptValue(instanceId, sessionId, prompt())
+          setSessionDraftPrompt(instanceId, sessionId, prompt())
         })
 
-        const storedPrompt = getPromptValue(instanceId, sessionId)
+        const storedPrompt = getSessionDraftPrompt(instanceId, sessionId)
         const currentAttachments = untrack(() => getAttachments(instanceId, sessionId))
 
         setPromptInternal(storedPrompt)
-        setPromptValue(instanceId, sessionId, storedPrompt)
+        setSessionDraftPrompt(instanceId, sessionId, storedPrompt)
         setHistoryIndex(-1)
         setIgnoredAtPositions(new Set<number>())
         setShowPicker(false)
@@ -134,9 +133,8 @@ export default function PromptInput(props: PromptInputProps) {
         queueMicrotask(() => {
           adjustTextareaHeight(textareaRef)
         })
-      },
+      }
-      { defer: true },
+    )
-    ),
   )
 
   function handleRemoveAttachment(attachmentId: string) {

src/stores/instances.ts

@@ -2,7 +2,13 @@ import { createSignal } from "solid-js"
 import type { Instance, LogEntry } from "../types/instance"
 import { sdkManager } from "../lib/sdk-manager"
 import { sseManager } from "../lib/sse-manager"
-import { fetchSessions, fetchAgents, fetchProviders, removeSessionIndexes } from "./sessions"
+import {
+  fetchSessions,
+  fetchAgents,
+  fetchProviders,
+  removeSessionIndexes,
+  clearInstanceDraftPrompts,
+} from "./sessions"
 import { preferences, updateLastUsedBinary } from "./preferences"
 
 const [instances, setInstances] = createSignal<Map<string, Instance>>(new Map())
@@ -69,8 +75,9 @@ function removeInstance(id: string) {
     setActiveInstanceId(null)
   }
 
-  // Clean up session indexes for removed instance
+  // Clean up session indexes and drafts for removed instance
   removeSessionIndexes(id)
+  clearInstanceDraftPrompts(id)
 }
 
 async function createInstance(folder: string, binaryPath?: string): Promise<string> {

src/stores/prompt-state.ts

@@ -1,34 +0,0 @@
-import { createSignal } from "solid-js"
-
-function getSessionKey(instanceId: string, sessionId: string): string {
-  return `${instanceId}:${sessionId}`
-}
-
-const [prompts, setPrompts] = createSignal<Map<string, string>>(new Map())
-
-export function getPromptValue(instanceId: string, sessionId: string): string {
-  const key = getSessionKey(instanceId, sessionId)
-  return prompts().get(key) || ""
-}
-
-export function setPromptValue(instanceId: string, sessionId: string, value: string) {
-  const key = getSessionKey(instanceId, sessionId)
-  setPrompts((prev) => {
-    const next = new Map(prev)
-    if (value.length === 0) {
-      next.delete(key)
-    } else {
-      next.set(key, value)
-    }
-    return next
-  })
-}
-
-export function clearPromptValue(instanceId: string, sessionId: string) {
-  const key = getSessionKey(instanceId, sessionId)
-  setPrompts((prev) => {
-    const next = new Map(prev)
-    next.delete(key)
-    return next
-  })
-}

src/stores/sessions.ts

@@ -25,6 +25,74 @@ const [activeSessionId, setActiveSessionId] = createSignal<Map<string, string>>(
 const [activeParentSessionId, setActiveParentSessionId] = createSignal<Map<string, string>>(new Map())
 const [agents, setAgents] = createSignal<Map<string, Agent[]>>(new Map())
 const [providers, setProviders] = createSignal<Map<string, Provider[]>>(new Map())
+const [sessionDraftPrompts, setSessionDraftPrompts] = createSignal<Map<string, string>>(new Map())
+
+function getDraftKey(instanceId: string, sessionId: string): string {
+  return `${instanceId}:${sessionId}`
+}
+
+function getSessionDraftPrompt(instanceId: string, sessionId: string): string {
+  if (!instanceId || !sessionId) return ""
+  const key = getDraftKey(instanceId, sessionId)
+  return sessionDraftPrompts().get(key) ?? ""
+}
+
+function setSessionDraftPrompt(instanceId: string, sessionId: string, value: string) {
+  const key = getDraftKey(instanceId, sessionId)
+  setSessionDraftPrompts((prev) => {
+    const next = new Map(prev)
+    if (!value) {
+      next.delete(key)
+    } else {
+      next.set(key, value)
+    }
+    return next
+  })
+}
+
+function clearSessionDraftPrompt(instanceId: string, sessionId: string) {
+  const key = getDraftKey(instanceId, sessionId)
+  setSessionDraftPrompts((prev) => {
+    if (!prev.has(key)) return prev
+    const next = new Map(prev)
+    next.delete(key)
+    return next
+  })
+}
+
+function clearInstanceDraftPrompts(instanceId: string) {
+  if (!instanceId) return
+  setSessionDraftPrompts((prev) => {
+    let changed = false
+    const next = new Map(prev)
+    const prefix = `${instanceId}:`
+    for (const key of Array.from(next.keys())) {
+      if (key.startsWith(prefix)) {
+        next.delete(key)
+        changed = true
+      }
+    }
+    return changed ? next : prev
+  })
+}
+
+function pruneDraftPrompts(instanceId: string, validSessionIds: Set<string>) {
+  setSessionDraftPrompts((prev) => {
+    let changed = false
+    const next = new Map(prev)
+    const prefix = `${instanceId}:`
+    for (const key of Array.from(next.keys())) {
+      if (key.startsWith(prefix)) {
+        const sessionId = key.slice(prefix.length)
+        if (!validSessionIds.has(sessionId)) {
+          next.delete(key)
+          changed = true
+        }
+      }
+    }
+    return changed ? next : prev
+  })
+}
 
 const [loading, setLoading] = createSignal({
   fetchingSessions: new Map<string, boolean>(),
@@ -323,6 +391,8 @@ async function fetchSessions(instanceId: string): Promise<void> {
       next.set(instanceId, sessionMap)
       return next
     })
+
+    pruneDraftPrompts(instanceId, new Set(sessionMap.keys()))
   } catch (error) {
     console.error("Failed to fetch sessions:", error)
     throw error
@@ -736,6 +806,8 @@ async function deleteSession(instanceId: string, sessionId: string): Promise<voi
       return next
     })
 
+    clearSessionDraftPrompt(instanceId, sessionId)
+
     // Remove session info entry
     setSessionInfoByInstance((prev) => {
       const next = new Map(prev)
@@ -1788,4 +1860,8 @@ export {
   updateSessionModel,
   getDefaultModel,
   removeSessionIndexes,
+  getSessionDraftPrompt,
+  setSessionDraftPrompt,
+  clearSessionDraftPrompt,
+  clearInstanceDraftPrompts,
 }