refactor: MCP層をmcpc APIベースに刷新

- 独自JSON-RPC処理をmcpcへ置き換え
- 各MCPツールを個別ソースへ分離
- 共通コンテキストと登録処理を整理
- mcpc互換修正と統合テストを更新

1 files changed, 134 insertions, 0 deletions

diff --git a/src/mcp/tools/search_messages.c b/src/mcp/tools/search_messages.c
new file mode 100644
index 0000000..166c167
--- /dev/null
+++ b/src/mcp/tools/search_messages.c
@@ -0,0 +1,134 @@
+#include "mcp/tools/common/registry.h"
+
+#include "mcp/tools/common/common.h"
+#include "mcp/tools/common/context.h"
+
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "base/allocator.h"
+
+typedef struct result_item
+{
+  const tiny_store_entry_t *entry;
+  double score;
+} result_item_t;
+
+static int
+compare_results(const void *left, const void *right)
+{
+  const result_item_t *a = left;
+  const result_item_t *b = right;
+  if (a->score > b->score)
+    {
+      return -1;
+    }
+  if (a->score < b->score)
+    {
+      return 1;
+    }
+  if (a->entry->message.timestamp_ms > b->entry->message.timestamp_ms)
+    {
+      return -1;
+    }
+  if (a->entry->message.timestamp_ms < b->entry->message.timestamp_ms)
+    {
+      return 1;
+    }
+  return strcmp(a->entry->message.message_id, b->entry->message.message_id);
+}
+
+static void
+call_search_messages(const mcpc_tool_t *tool, mcpc_ucbr_t *result)
+{
+  tiny_mcp_tools_context_t *context = tiny_mcp_tools_context_current();
+  char *query = tiny_mcp_tool_get_string(tool, "query", TINY_QUERY_MAX);
+  char *session = tiny_mcp_tool_get_string(tool, "session_id", TINY_SESSION_ID_MAX);
+  int32_t requested_limit = 0;
+  size_t limit, index, count = 0, candidate_count = 0, *candidates = NULL;
+  result_item_t *items = NULL;
+  tiny_json_buffer_t json;
+  bool valid
+      = context && query && query[0] && session
+        && mcpc_tool_get_tpropval_i32(tool, (const char8_t *)"limit", &requested_limit) == MCPC_EC_0
+        && requested_limit >= 1 && requested_limit <= 100;
+  if (!valid)
+    {
+      tiny_mcp_tool_add_error(result, "VALIDATION_ERROR", "query or limit is invalid");
+    }
+  else
+    {
+      limit = (size_t)requested_limit;
+      if (!context->search_index)
+        {
+          context->search_index = tiny_mcp_tools_build_search_index(context->store);
+        }
+      if (!context->search_index
+          || !tiny_search_index_candidates(
+              context->search_index, query, &candidates, &candidate_count))
+        {
+          tiny_mcp_tool_add_error(result, "INTERNAL_ERROR", "search index allocation failed");
+        }
+      else
+        {
+          items = malloc((candidate_count + 1) * sizeof(*items));
+          if (!items)
+            {
+              tiny_mcp_tool_add_error(result, "INTERNAL_ERROR", "out of memory");
+            }
+          else
+            {
+              for (index = 0; index < candidate_count; ++index)
+                {
+                  const tiny_store_entry_t *entry
+                      = tiny_store_entry(context->store, candidates[index]);
+                  double score;
+                  if (!entry || entry->deleted
+                      || (session[0] && strcmp(entry->message.session_id, session) != 0))
+                    {
+                      continue;
+                    }
+                  score = tiny_search_score(query, &entry->message);
+                  if (score > 0)
+                    {
+                      items[count].entry = entry;
+                      items[count++].score = score;
+                    }
+                }
+              qsort(items, count, sizeof(*items), compare_results);
+              if (count > limit)
+                {
+                  count = limit;
+                }
+              tiny_json_init(&json);
+              tiny_json_raw(&json, "{\"results\":[");
+              for (index = 0; index < count; ++index)
+                {
+                  if (index)
+                    {
+                      tiny_json_raw(&json, ",");
+                    }
+                  tiny_mcp_tool_append_message(&json, &items[index].entry->message);
+                }
+              tiny_json_raw(&json, "]}");
+              tiny_mcp_tool_add_json(result, &json);
+              tiny_json_free(&json);
+            }
+        }
+    }
+  free(items);
+  free(candidates);
+  free(query);
+  free(session);
+}
+
+bool
+tiny_mcp_register_search_messages(mcpc_server_t *server)
+{
+  mcpc_tool_t *tool = tiny_mcp_tool_new("search_messages", "Search messages", call_search_messages);
+  return tool && tiny_mcp_tool_add_property(tool, "query", "Search text", MCPC_U8STR)
+         && tiny_mcp_tool_add_property(tool, "session_id", "Session ID; empty for all", MCPC_U8STR)
+         && tiny_mcp_tool_add_property(tool, "limit", "Result limit from 1 to 100", MCPC_I32)
+         && mcpc_server_add_tool(server, tool) == MCPC_EC_0;
+}