Merge pull request #19988 from brave/ai-chat-prompt-abstraction

AI Chat: refactor prompt building and engine calling to EngineConsumer implementations

Author: petemill

browser/ui/webui/ai_chat/ai_chat_ui_page_handler.cc

@@ -81,22 +81,10 @@ void AIChatUIPageHandler::SetClientPage(
 
 void AIChatUIPageHandler::SubmitHumanConversationEntry(
     const std::string& input) {
-  // TODO(nullhook): Avoid copy
-  std::string input_copy = input;
-
-  // Prevent indirect prompt injections being sent to the AI model.
-  // TODO(nullhook): Abstract prompt injection cleanups to a central place
-  base::ReplaceSubstringsAfterOffset(&input_copy, 0, ai_chat::kHumanPrompt, "");
-  base::ReplaceSubstringsAfterOffset(&input_copy, 0, ai_chat::kAIPrompt, "");
-  base::ReplaceSubstringsAfterOffset(&input_copy, 0, "<article>", "");
-  base::ReplaceSubstringsAfterOffset(&input_copy, 0, "</article>", "");
-  base::ReplaceSubstringsAfterOffset(&input_copy, 0, "<history>", "");
-  base::ReplaceSubstringsAfterOffset(&input_copy, 0, "</history>", "");
-  base::ReplaceSubstringsAfterOffset(&input_copy, 0, "<question>", "");
-  base::ReplaceSubstringsAfterOffset(&input_copy, 0, "</question>", "");
-
+  mojom::ConversationTurn turn = {CharacterType::HUMAN,
+                                  ConversationTurnVisibility::VISIBLE, input};
   active_chat_tab_helper_->MakeAPIRequestWithConversationHistoryUpdate(
-      {CharacterType::HUMAN, ConversationTurnVisibility::VISIBLE, input_copy});
+      std::move(turn));
 }
 
 void AIChatUIPageHandler::GetConversationHistory(

components/ai_chat/browser/BUILD.gn

@@ -13,14 +13,19 @@ if (is_official_build) {
 
 static_library("browser") {
   sources = [
-    "ai_chat_api.cc",
-    "ai_chat_api.h",
     "ai_chat_metrics.cc",
     "ai_chat_metrics.h",
     "ai_chat_tab_helper.cc",
     "ai_chat_tab_helper.h",
     "constants.cc",
     "constants.h",
+    "engine/engine_consumer.h",
+    "engine/engine_consumer_claude.cc",
+    "engine/engine_consumer_claude.h",
+    "engine/engine_consumer_llama.cc",
+    "engine/engine_consumer_llama.h",
+    "engine/remote_completion_client.cc",
+    "engine/remote_completion_client.h",
     "page_content_fetcher.cc",
     "page_content_fetcher.h",
   ]

components/ai_chat/browser/DEPS

@@ -3,5 +3,6 @@ include_rules = [
   "+services/data_decoder/public",
   "+services/network/public",
   "+services/service_manager/public",
+  "+absl/types/optional.h",
   "+ui",
 ]