feat(server.py): add InsertTextFileContentsHandler for inserting content in text files

fix(test_server.py): update tool count in test to reflect new InsertTextFileContentsHandler addition

Author: tumfwkm

src/mcp_text_editor/server.py

@@ -521,12 +521,105 @@ async def run_tool(self, arguments: Dict[str, Any]) -> Sequence[TextContent]:
             raise RuntimeError(f"Error processing request: {str(e)}") from e
 
 
+class InsertTextFileContentsHandler:
+    """Handler for inserting content before or after a specific line in a text file."""
+
+    name = "insert_text_file_contents"
+    description = "Insert content before or after a specific line in a text file. Uses hash-based validation for concurrency control."
+
+    def __init__(self):
+        self.editor = TextEditor()
+
+    def get_tool_description(self) -> Tool:
+        """Get the tool description."""
+        return Tool(
+            name=self.name,
+            description=self.description,
+            inputSchema={
+                "type": "object",
+                "properties": {
+                    "path": {
+                        "type": "string",
+                        "description": "Path to the text file. File path must be absolute.",
+                    },
+                    "file_hash": {
+                        "type": "string",
+                        "description": "Hash of the file contents for concurrency control",
+                    },
+                    "contents": {
+                        "type": "string",
+                        "description": "Content to insert",
+                    },
+                    "before": {
+                        "type": "integer",
+                        "description": "Line number before which to insert content (mutually exclusive with 'after')",
+                    },
+                    "after": {
+                        "type": "integer",
+                        "description": "Line number after which to insert content (mutually exclusive with 'before')",
+                    },
+                    "encoding": {
+                        "type": "string",
+                        "description": "Text encoding (default: 'utf-8')",
+                        "default": "utf-8",
+                    },
+                },
+                "required": ["path", "file_hash", "contents"],
+            },
+        )
+
+    async def run_tool(self, arguments: Dict[str, Any]) -> Sequence[TextContent]:
+        """Execute the tool with given arguments."""
+        try:
+            if "path" not in arguments:
+                raise RuntimeError("Missing required argument: path")
+            if "file_hash" not in arguments:
+                raise RuntimeError("Missing required argument: file_hash")
+            if "contents" not in arguments:
+                raise RuntimeError("Missing required argument: contents")
+
+            file_path = arguments["path"]
+            if not os.path.isabs(file_path):
+                raise RuntimeError(f"File path must be absolute: {file_path}")
+
+            # Check if exactly one of before/after is specified
+            if ("before" in arguments) == ("after" in arguments):
+                raise RuntimeError(
+                    "Exactly one of 'before' or 'after' must be specified"
+                )
+
+            line_number = (
+                arguments.get("before")
+                if "before" in arguments
+                else arguments.get("after")
+            )
+            is_before = "before" in arguments
+            encoding = arguments.get("encoding", "utf-8")
+
+            result = await self.editor.insert_text_file_contents(
+                file_path=file_path,
+                file_hash=arguments["file_hash"],
+                contents=arguments["contents"],
+                before=is_before,
+                line_number=line_number,
+                encoding=encoding,
+            )
+
+            return [TextContent(type="text", text=json.dumps(result, indent=2))]
+
+        except Exception as e:
+            logger.error(f"Error processing request: {str(e)}")
+            logger.error(traceback.format_exc())
+            raise RuntimeError(f"Error processing request: {str(e)}") from e
+
+
 # Initialize tool handlers
 get_contents_handler = GetTextFileContentsHandler()
 edit_contents_handler = EditTextFileContentsHandler()
 create_file_handler = CreateTextFileHandler()
 append_file_handler = AppendTextFileContentsHandler()
 delete_contents_handler = DeleteTextFileContentsHandler()
+insert_file_handler = InsertTextFileContentsHandler()
 
 
 @app.list_tools()
@@ -538,6 +631,7 @@ async def list_tools() -> List[Tool]:
         create_file_handler.get_tool_description(),
         append_file_handler.get_tool_description(),
         delete_contents_handler.get_tool_description(),
+        insert_file_handler.get_tool_description(),
     ]
 
 
@@ -556,6 +650,8 @@ async def call_tool(name: str, arguments: Any) -> Sequence[TextContent]:
             return await append_file_handler.run_tool(arguments)
         elif name == delete_contents_handler.name:
             return await delete_contents_handler.run_tool(arguments)
+        elif name == insert_file_handler.name:
+            return await insert_file_handler.run_tool(arguments)
         else:
             raise ValueError(f"Unknown tool: {name}")
     except ValueError: