reorganize lsp code

1 files changed, 329 insertions, 0 deletions

diff --git a/lsp-parse.c b/lsp-parse.c
new file mode 100644
index 0000000..6167cc8
--- /dev/null
+++ b/lsp-parse.c
@@ -0,0 +1,329 @@
+static WarnUnusedResult bool lsp_expect_type(LSP *lsp, JSONValue value, JSONValueType type, const char *what) {
+	if (value.type != type) {
+		lsp_set_error(lsp, "Expected %s for %s, got %s",
+			json_type_to_str(type),
+			what,
+			json_type_to_str(value.type));
+		return false;
+	}
+	return true;
+}
+
+static WarnUnusedResult bool lsp_expect_object(LSP *lsp, JSONValue value, const char *what) {
+	return lsp_expect_type(lsp, value, JSON_OBJECT, what);
+}
+
+static WarnUnusedResult bool lsp_expect_array(LSP *lsp, JSONValue value, const char *what) {
+	return lsp_expect_type(lsp, value, JSON_ARRAY, what);
+}
+
+static WarnUnusedResult bool lsp_expect_string(LSP *lsp, JSONValue value, const char *what) {
+	return lsp_expect_type(lsp, value, JSON_STRING, what);
+}
+
+static WarnUnusedResult bool lsp_expect_number(LSP *lsp, JSONValue value, const char *what) {
+	return lsp_expect_type(lsp, value, JSON_NUMBER, what);
+}
+
+static LSPString lsp_response_add_json_string(LSPResponse *response, const JSON *json, JSONString string) {
+	u32 offset = arr_len(response->string_data);
+	arr_set_len(response->string_data, offset + string.len + 1);
+	json_string_get(json, string, response->string_data + offset, string.len + 1);
+	return (LSPString){
+		.offset = offset
+	};
+}
+
+static int completion_qsort_cmp(void *context, const void *av, const void *bv) {
+	const LSPResponse *response = context;
+	const LSPCompletionItem *a = av, *b = bv;
+	const char *a_sort_text = lsp_response_string(response, a->sort_text);
+	const char *b_sort_text = lsp_response_string(response, b->sort_text);
+	int sort_text_cmp = strcmp(a_sort_text, b_sort_text);
+	if (sort_text_cmp != 0)
+		return sort_text_cmp;
+	// for some reason, rust-analyzer outputs identical sortTexts
+	// i have no clue what that means.
+	// the LSP "specification" is not very specific.
+	// we'll sort by label in this case.
+	// this is what VSCode seems to do.
+	// i hate microsofot.
+	const char *a_label = lsp_response_string(response, a->label);
+	const char *b_label = lsp_response_string(response, b->label);
+	return strcmp(a_label, b_label);
+}
+
+static bool parse_position(LSP *lsp, const JSON *json, JSONValue pos_value, LSPPosition *pos) {
+	if (!lsp_expect_object(lsp, pos_value, "document position"))
+		return false;
+	JSONObject pos_object = pos_value.val.object;
+	JSONValue line = json_object_get(json, pos_object, "line");
+	JSONValue character = json_object_get(json, pos_object, "character");
+	if (!lsp_expect_number(lsp, line, "document line number")
+		|| !lsp_expect_number(lsp, character, "document column number"))
+		return false;
+	pos->line = (u32)line.val.number;
+	pos->character = (u32)line.val.number;
+	return true;
+}
+
+static bool parse_range(LSP *lsp, const JSON *json, JSONValue range_value, LSPRange *range) {
+	if (!lsp_expect_object(lsp, range_value, "document range"))
+		return false;
+	JSONObject range_object = range_value.val.object;
+	JSONValue start = json_object_get(json, range_object, "start");
+	JSONValue end = json_object_get(json, range_object, "end");
+	return parse_position(lsp, json, start, &range->start)
+		&& parse_position(lsp, json, end, &range->end);
+}
+
+static bool parse_completion(LSP *lsp, const JSON *json, LSPResponse *response) {
+	// deal with textDocument/completion response.
+	// result: CompletionItem[] | CompletionList | null
+	LSPResponseCompletion *completion = &response->data.completion;
+	
+	JSONValue result = json_get(json, "result");
+	JSONValue items_value = {0};
+	switch (result.type) {
+	case JSON_NULL:
+		// no completions
+		return true;
+	case JSON_ARRAY:
+		items_value = result;
+		break;
+	case JSON_OBJECT:
+		items_value = json_object_get(json, result.val.object, "items");
+		break;
+	default:
+		lsp_set_error(lsp, "Weird result type for textDocument/completion response: %s.", json_type_to_str(result.type));
+		break;		
+	}
+		
+	if (!lsp_expect_array(lsp, items_value, "completion list"))
+		return false;
+	
+	JSONArray items = items_value.val.array;
+	
+	arr_set_len(completion->items, items.len);
+	
+	for (u32 i = 0; i < items.len; ++i) {
+		LSPCompletionItem *item = &completion->items[i];
+		
+		JSONValue item_value = json_array_get(json, items, i);
+		if (!lsp_expect_object(lsp, item_value, "completion list"))
+			return false;
+		JSONObject item_object = item_value.val.object;
+		
+		JSONValue label_value = json_object_get(json, item_object, "label");
+		if (!lsp_expect_string(lsp, label_value, "completion label"))
+			return false;
+		JSONString label = label_value.val.string;
+		item->label = lsp_response_add_json_string(response, json, label);
+		
+		// defaults
+		item->sort_text = item->label;
+		item->filter_text = item->label;
+		item->text_edit = (LSPTextEdit) {
+			.type = LSP_TEXT_EDIT_PLAIN,
+			.at_cursor = true,
+			.range = {0},
+			.new_text = item->label
+		};
+		
+		JSONValue sort_text_value = json_object_get(json, item_object, "sortText");
+		if (sort_text_value.type == JSON_STRING) {
+			// LSP allows using a different string for sorting.
+			item->sort_text = lsp_response_add_json_string(response,
+				json, sort_text_value.val.string);
+		}
+		
+		JSONValue filter_text_value = json_object_get(json, item_object, "filterText");
+		if (filter_text_value.type == JSON_STRING) {
+			// LSP allows using a different string for filtering.
+			item->filter_text = lsp_response_add_json_string(response,
+				json, filter_text_value.val.string);
+		}
+		
+		JSONValue text_type_value = json_object_get(json, item_object, "insertTextFormat");
+		if (text_type_value.type == JSON_NUMBER) {
+			double type = text_type_value.val.number;
+			if (type != LSP_TEXT_EDIT_PLAIN && type != LSP_TEXT_EDIT_SNIPPET) {
+				lsp_set_error(lsp, "Bad InsertTextFormat: %g", type);
+				return false;
+			}
+			item->text_edit.type = (LSPTextEditType)type;
+		}
+		
+		// @TODO: detail
+		
+		// @TODO(eventually): additionalTextEdits
+		//  (try to find a case where this comes up)
+		
+		// what should happen when this completion is selected?
+		JSONValue text_edit_value = json_object_get(json, item_object, "textEdit");
+		if (text_edit_value.type == JSON_OBJECT) {
+			JSONObject text_edit = text_edit_value.val.object;
+			item->text_edit.at_cursor = false;
+			
+			JSONValue range = json_object_get(json, text_edit, "range");
+			if (!parse_range(lsp, json, range, &item->text_edit.range))
+				return false;
+				
+			JSONValue new_text_value = json_object_get(json, text_edit, "newText");
+			if (!lsp_expect_string(lsp, new_text_value, "completion newText"))
+				return false;
+			item->text_edit.new_text = lsp_response_add_json_string(response,
+				json, new_text_value.val.string);
+		} else {
+			// not using textEdit. check insertText.
+			JSONValue insert_text_value = json_object_get(json, item_object, "insertText");
+			if (insert_text_value.type == JSON_STRING) {
+				// string which will be inserted if this completion is selected
+				item->text_edit.new_text = lsp_response_add_json_string(response,
+					json, insert_text_value.val.string);
+			}
+		}
+		
+	}
+	
+	qsort_with_context(completion->items, items.len, sizeof *completion->items,
+		completion_qsort_cmp, response);
+	
+	return true;
+}
+
+static bool parse_server2client_request(LSP *lsp, JSON *json, LSPRequest *request) {
+	JSONValue method_value = json_get(json, "method");
+	if (!lsp_expect_string(lsp, method_value, "request method"))
+		return false;
+	
+	char method[64] = {0};
+	json_string_get(json, method_value.val.string, method, sizeof method);
+	
+	if (streq(method, "window/showMessage")) {
+		request->type = LSP_REQUEST_SHOW_MESSAGE;
+		goto window_message;
+	} else if (streq(method, "window/logMessage")) {
+		request->type = LSP_REQUEST_LOG_MESSAGE;
+		window_message:;
+		JSONValue type = json_get(json, "params.type");
+		JSONValue message = json_get(json, "params.message");
+		if (!lsp_expect_number(lsp, type, "MessageType"))
+			return false;
+		if (!lsp_expect_string(lsp, message, "message string"))
+			return false;
+		
+		int mtype = (int)type.val.number;
+		if (mtype < 1 || mtype > 4) {
+			lsp_set_error(lsp, "Bad MessageType: %g", type.val.number);
+			return false;
+		}
+		
+		LSPRequestMessage *m = &request->data.message;
+		m->type = (LSPWindowMessageType)mtype;
+		m->message = json_string_get_alloc(json, message.val.string);
+		return true;
+	} else if (str_has_prefix(method, "$/")) {
+		// we can safely ignore this
+	} else {
+		lsp_set_error(lsp, "Unrecognized request method: %s", method);
+	}
+	return false;
+}
+
+
+static void process_message(LSP *lsp, JSON *json) {
+		
+	#if 0
+	printf("\x1b[3m");
+	json_debug_print(json);
+	printf("\x1b[0m\n");
+	#endif
+	JSONValue id_value = json_get(json, "id");
+	
+	// get the request associated with this (if any)
+	LSPRequest response_to = {0};
+	if (id_value.type == JSON_NUMBER) {
+		u64 id = (u64)id_value.val.number;
+		arr_foreach_ptr(lsp->requests_sent, LSPRequest, req) {
+			if (req->id == id) {
+				response_to = *req;
+				arr_remove(lsp->requests_sent, (u32)(req - lsp->requests_sent));
+				break;
+			}
+		}
+	}
+	
+	JSONValue error = json_get(json, "error.message");
+	if (error.type == JSON_STRING) {
+		char err[256] = {0};
+		json_string_get(json, error.val.string, err, sizeof err);;
+		
+		if (streq(err, "waiting for cargo metadata or cargo check")) {
+			// fine. be that way. i'll resend the goddamn request.
+			// i'll keep bombarding you with requests.
+			// maybe next time you should abide by the standard and only send an initialize response when youre actually ready to handle my requests. fuck you.
+			if (response_to.type) {
+				lsp_send_request(lsp, &response_to);
+				// don't free
+				memset(&response_to, 0, sizeof response_to);
+			}
+		} else {
+			lsp_set_error(lsp, "%s", err);
+		}
+		goto ret;
+	}
+	
+	JSONValue result = json_get(json, "result");
+	if (result.type != JSON_UNDEFINED) {
+		if (response_to.type == LSP_REQUEST_INITIALIZE) {
+			// it's the response to our initialize request!
+			// let's send back an "initialized" request (notification) because apparently
+			// that's something we need to do.
+			LSPRequest initialized = {
+				.type = LSP_REQUEST_INITIALIZED,
+				.data = {0},
+			};
+			write_request(lsp, &initialized);
+			// we can now send requests which have nothing to do with initialization
+			lsp->initialized = true;
+		} else {
+			LSPResponse response = {0};
+			bool success = false;
+			response.request = response_to;
+			switch (response_to.type) {
+			case LSP_REQUEST_COMPLETION:
+				success = parse_completion(lsp, json, &response);
+				break;
+			default:
+				// it's some response we don't care about
+				break;
+			}
+			if (success) {
+				SDL_LockMutex(lsp->messages_mutex);
+				LSPMessage *message = arr_addp(lsp->messages);
+				message->type = LSP_RESPONSE;
+				message->u.response = response;
+				SDL_UnlockMutex(lsp->messages_mutex);
+				response_to.type = 0; // don't free
+			} else {
+				lsp_response_free(&response);
+			}
+		}
+	} else if (json_has(json, "method")) {
+		LSPRequest request = {0};
+		if (parse_server2client_request(lsp, json, &request)) {
+			SDL_LockMutex(lsp->messages_mutex);
+			LSPMessage *message = arr_addp(lsp->messages);
+			message->type = LSP_REQUEST;
+			message->u.request = request;
+			SDL_UnlockMutex(lsp->messages_mutex);
+		}
+	} else {
+		lsp_set_error(lsp, "Bad message from server (no result, no method).");
+	}
+	ret:
+	lsp_request_free(&response_to);
+	json_free(json);
+	
+}