From f69820e76e79e55e88a678818d35d57c2ea537bc Mon Sep 17 00:00:00 2001
From: YeonGyu-Kim <code.yeon.gyu@gmail.com>
Date: Sun, 15 Feb 2026 14:54:58 +0900
Subject: [PATCH] feat: implement SQLite backend for prependThinkingPart via
 HTTP PATCH

---
 .../storage/thinking-prepend.ts               | 63 ++++++++++++++++++-
 1 file changed, 61 insertions(+), 2 deletions(-)

diff --git a/src/hooks/session-recovery/storage/thinking-prepend.ts b/src/hooks/session-recovery/storage/thinking-prepend.ts
index 6ddffb06..c63a57fb 100644
--- a/src/hooks/session-recovery/storage/thinking-prepend.ts
+++ b/src/hooks/session-recovery/storage/thinking-prepend.ts
@@ -1,9 +1,13 @@
 import { existsSync, mkdirSync, writeFileSync } from "node:fs"
 import { join } from "node:path"
+import type { PluginInput } from "@opencode-ai/plugin"
 import { PART_STORAGE, THINKING_TYPES } from "../constants"
+import type { MessageData } from "../types"
 import { readMessages } from "./messages-reader"
 import { readParts } from "./parts-reader"
-import { log, isSqliteBackend } from "../../../shared"
+import { log, isSqliteBackend, patchPart } from "../../../shared"
+
+type OpencodeClient = PluginInput["client"]
 
 function findLastThinkingContent(sessionID: string, beforeMessageID: string): string {
   const messages = readMessages(sessionID)
@@ -33,7 +37,7 @@ function findLastThinkingContent(sessionID: string, beforeMessageID: string): st
 
 export function prependThinkingPart(sessionID: string, messageID: string): boolean {
   if (isSqliteBackend()) {
-    log("[session-recovery] Disabled on SQLite backend: prependThinkingPart")
+    log("[session-recovery] Disabled on SQLite backend: prependThinkingPart (use async variant)")
     return false
   }
 
@@ -62,3 +66,58 @@ export function prependThinkingPart(sessionID: string, messageID: string): boole
     return false
   }
 }
+
+async function findLastThinkingContentFromSDK(
+  client: OpencodeClient,
+  sessionID: string,
+  beforeMessageID: string
+): Promise<string> {
+  try {
+    const response = await client.session.messages({ path: { id: sessionID } })
+    const messages = (response.data ?? []) as MessageData[]
+
+    const currentIndex = messages.findIndex((m) => m.info?.id === beforeMessageID)
+    if (currentIndex === -1) return ""
+
+    for (let i = currentIndex - 1; i >= 0; i--) {
+      const msg = messages[i]
+      if (msg.info?.role !== "assistant") continue
+      if (!msg.parts) continue
+
+      for (const part of msg.parts) {
+        if (part.type && THINKING_TYPES.has(part.type)) {
+          const content = part.thinking || part.text
+          if (content && content.trim().length > 0) return content
+        }
+      }
+    }
+  } catch {
+    return ""
+  }
+  return ""
+}
+
+export async function prependThinkingPartAsync(
+  client: OpencodeClient,
+  sessionID: string,
+  messageID: string
+): Promise<boolean> {
+  const previousThinking = await findLastThinkingContentFromSDK(client, sessionID, messageID)
+
+  const partId = "prt_0000000000_thinking"
+  const part: Record<string, unknown> = {
+    id: partId,
+    sessionID,
+    messageID,
+    type: "thinking",
+    thinking: previousThinking || "[Continuing from previous reasoning]",
+    synthetic: true,
+  }
+
+  try {
+    return await patchPart(client, sessionID, messageID, partId, part)
+  } catch (error) {
+    log("[session-recovery] prependThinkingPartAsync failed", { error: String(error) })
+    return false
+  }
+}