src/GuileHandler.h
branchv_0
changeset 33 e87c231afb77
parent 32 2354c9058fb6
child 34 6a16b36ab852
--- a/src/GuileHandler.h	Sat Jun 06 01:50:45 2020 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,321 +0,0 @@
-/**
- * Relational pipes
- * Copyright © 2019 František Kučera (Frantovo.cz, GlobalCode.info)
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, version 3 of the License.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
-#pragma once
-
-#include <memory>
-#include <string>
-#include <vector>
-#include <map>
-#include <iostream>
-#include <sstream>
-#include <locale>
-#include <codecvt>
-#include <regex>
-#include <assert.h>
-
-#include <libguile.h>
-
-#include <relpipe/reader/typedefs.h>
-#include <relpipe/reader/TypeId.h>
-#include <relpipe/reader/handlers/RelationalReaderValueHandler.h>
-#include <relpipe/reader/handlers/AttributeMetadata.h>
-
-#include <relpipe/writer/Factory.h>
-
-#include <relpipe/cli/RelpipeCLIException.h>
-
-#include "Configuration.h"
-#include "GuileException.h"
-
-namespace relpipe {
-namespace tr {
-namespace guile {
-
-using namespace std;
-using namespace relpipe;
-using namespace relpipe::reader;
-using namespace relpipe::reader::handlers;
-
-class GuileHandler : public RelationalReaderValueHandler {
-private:
-	std::wstring_convert<codecvt_utf8<wchar_t>> convertor; // TODO: support also other encodings or use always UTF-8 between C++ and Guile
-
-	Configuration configuration;
-	writer::RelationalWriter* relationalWriter;
-
-	RelationConfiguration* currentRelationConfiguration = nullptr;
-	vector<AttributeMetadata> currentReaderMetadata;
-	vector<writer::AttributeMetadata> currentWriterMetadata;
-	std::map<string_t, string_t> currenVariablesMapping;
-	integer_t currentAttributeIndex = 0;
-	boolean_t includeCurrentRecord = false;
-
-	void add(vector<AttributeMetadata>& readerAttributes, vector<writer::AttributeMetadata>& writerAttributes) {
-		for (AttributeMetadata readerAttributes : readerAttributes)
-			writerAttributes.push_back({
-				readerAttributes.getAttributeName(),
-				relationalWriter->toTypeId(readerAttributes.getTypeName())
-			});
-	}
-
-	void generateVariableMappings() {
-		currenVariablesMapping.clear();
-		for (AttributeMetadata m : currentReaderMetadata) currenVariablesMapping[m.getAttributeName()] = L"";
-		for (writer::AttributeMetadata m : currentWriterMetadata) currenVariablesMapping[m.attributeName] = L"";
-
-		for (std::pair<string_t, string_t> m : currenVariablesMapping) {
-			currenVariablesMapping[m.first] = escapeAwkVariableName(m.first);
-		}
-	}
-
-	/**
-	 * @param attributeName name from relational pipe
-	 * @return variable name in Guile
-	 */
-	string_t a2v(const string_t& attributeName) {
-		if (currenVariablesMapping.find(attributeName) != currenVariablesMapping.end()) return currenVariablesMapping[attributeName];
-		else throw GuileException(L"Unable to find value in currenVariablesMapping");
-	}
-
-	template <typename K, typename V> bool containsValue(std::map<K, V> map, V value) { // TODO: common function (Guile, AWK)
-		for (std::pair<K, V> p : map) if (p.second == value) return true;
-		return false;
-	}
-
-	string_t escapeAwkVariableName(const string_t& attributeName, bool addPrefix = true) {
-		std::wregex badCharacters(L"\\s");
-		string_t name = std::regex_replace(attributeName, badCharacters, L"-");
-
-		if (addPrefix) name = L"$" + name; // $ = standard attribute-variable prefix
-
-		if (containsValue(currenVariablesMapping, name)) return escapeAwkVariableName(L"$" + name, false); // $ = different prefix added to distinguish two attributes with ambiguous names
-		else return name;
-
-	}
-
-	void debugVariableMapping(const string_t& relationName) {
-		relationalWriter->startRelation(relationName + L".variableMapping",{
-			{L"attribute", writer::TypeId::STRING},
-			{L"variable", writer::TypeId::STRING},
-		}, true);
-
-		for (std::pair<string_t, string_t> m : currenVariablesMapping) {
-			relationalWriter->writeAttribute(m.first);
-			relationalWriter->writeAttribute(m.second);
-		}
-	}
-
-	SCM toGuileSymbol(const string_t& name) {
-		return scm_string_to_symbol(scm_from_locale_string(convertor.to_bytes(name).c_str()));
-	}
-
-	/**
-	 * @param code guile source code e.g. (+ 1 2 3) or #t
-	 * @param defaultReturnValue is returned if code is empty
-	 * @return result of code execution or defaultReturnValue
-	 */
-	SCM evalGuileCode(const string_t& code, SCM defaultReturnValue = SCM_BOOL_F) {
-		if (code.size()) return scm_eval_string(toGuileValue(&code, typeid (string_t), TypeId::STRING));
-		else return defaultReturnValue;
-	}
-
-	SCM toGuileValue(const void* value, const std::type_info& typeInfo, TypeId type) {
-		switch (type) {
-			case TypeId::BOOLEAN:
-			{
-				assert(typeInfo == typeid (boolean_t));
-				auto* typedValue = static_cast<const boolean_t*> (value);
-				return *typedValue ? SCM_BOOL_T : SCM_BOOL_F;
-			}
-			case TypeId::INTEGER:
-			{
-				assert(typeInfo == typeid (integer_t));
-				auto* typedValue = static_cast<const integer_t*> (value);
-				return scm_from_int64(*typedValue);
-			}
-			case TypeId::STRING:
-			{
-				assert(typeInfo == typeid (string_t));
-				auto* typedValue = static_cast<const string_t*> (value);
-				return scm_from_locale_string(convertor.to_bytes(*typedValue).c_str());
-			}
-			default:
-				throw cli::RelpipeCLIException(L"Unsupported type in toGuileValue()", cli::CLI::EXIT_CODE_UNEXPECTED_ERROR);
-		}
-	}
-
-	void defineGuileVariable(const string_t& name, const void* value, const std::type_info& typeInfo, TypeId type) {
-		scm_define(toGuileSymbol(name), toGuileValue(value, typeInfo, type));
-	}
-
-	/**
-	 * TODO: use a common method
-	 */
-	bool parseBoolean(const string_t& value) {
-		if (value == L"true") return true;
-		else if (value == L"false") return false;
-		else throw relpipe::cli::RelpipeCLIException(L"Unable to parse boolean value: " + value + L" (expecting true or false)", relpipe::cli::CLI::EXIT_CODE_BAD_CLI_ARGUMENTS);
-	}
-
-	void defineGuileVariable(const DefinitionRecipe& definition) {
-		switch (relationalWriter->toTypeId(definition.type)) {
-			case writer::TypeId::BOOLEAN:
-			{
-				boolean_t value = parseBoolean(definition.value);
-				defineGuileVariable(definition.name, &value, typeid (value), TypeId::BOOLEAN);
-				break;
-			}
-			case writer::TypeId::INTEGER:
-			{
-				integer_t value = stol(definition.value);
-				defineGuileVariable(definition.name, &value, typeid (value), TypeId::INTEGER);
-				break;
-			}
-			case writer::TypeId::STRING:
-			{
-				defineGuileVariable(definition.name, &definition.value, typeid (definition.value), TypeId::STRING);
-				break;
-			}
-			default:
-				throw cli::RelpipeCLIException(L"Unsupported type in defineGuileVariable(): " + definition.type, cli::CLI::EXIT_CODE_UNEXPECTED_ERROR);
-		}
-	}
-
-	void undefineGuileVariable(const string_t& name) {
-		scm_define(toGuileSymbol(name), scm_make_undefined_variable()); // undefined != (define n)
-		// TODO: or use: scm_variable_unset_x() ?
-	}
-
-	void writeGuileValueToAttribute(const writer::AttributeMetadata& attribute) {
-		string_t variableName = a2v(attribute.attributeName);
-		SCM guileValue = scm_eval_string(toGuileValue(&variableName, typeid (variableName), TypeId::STRING));
-
-		switch (attribute.typeId) {
-			case writer::TypeId::BOOLEAN:
-			{
-				boolean_t value = scm_to_bool(guileValue);
-				return relationalWriter->writeAttribute(&value, typeid (value));
-			}
-			case writer::TypeId::INTEGER:
-			{
-				integer_t value = scm_to_int64(guileValue);
-				return relationalWriter->writeAttribute(&value, typeid (value));
-			}
-			case writer::TypeId::STRING:
-			{
-				char* ch = scm_to_locale_string(guileValue);
-				string_t value = convertor.from_bytes(ch);
-				free(ch);
-				return relationalWriter->writeAttribute(&value, typeid (value));
-			}
-			default:
-				throw cli::RelpipeCLIException(L"Unsupported type in writeGuileValueToAttribute()", cli::CLI::EXIT_CODE_UNEXPECTED_ERROR);
-		}
-	}
-
-	/**
-	 * Read from the Guile variables and write to relational output stream.
-	 */
-	void writeCurrentRecord() {
-		for (auto attribute : currentWriterMetadata) writeGuileValueToAttribute(attribute);
-	}
-
-	void writeMoreRecords() {
-		while (scm_to_bool(evalGuileCode(currentRelationConfiguration->guileHasMoreRecords, SCM_BOOL_F))) writeCurrentRecord();
-	}
-
-public:
-
-	GuileHandler(writer::RelationalWriter* relationalWriter, Configuration& configuration) : relationalWriter(relationalWriter), configuration(configuration) {
-	}
-
-	void startRelation(string_t name, vector<AttributeMetadata> attributes) override {
-		if (currentRelationConfiguration) {
-			evalGuileCode(currentRelationConfiguration->guileAfterRecords);
-			writeMoreRecords();
-			for (DefinitionRecipe definition : currentRelationConfiguration->definitions) undefineGuileVariable(definition.name);
-		}
-		for (auto attribute : currentReaderMetadata) undefineGuileVariable(attribute.getAttributeName());
-
-		for (DefinitionRecipe definition : configuration.definitions) defineGuileVariable(definition);
-
-		currentRelationConfiguration = nullptr;
-		for (int i = 0; i < configuration.relationConfigurations.size(); i++) {
-			if (regex_match(name, wregex(configuration.relationConfigurations[i].relation))) {
-				currentRelationConfiguration = &configuration.relationConfigurations[i];
-				for (DefinitionRecipe definition : currentRelationConfiguration->definitions) defineGuileVariable(definition);
-				break; // it there are multiple matches, only the first configuration is used
-			}
-		}
-
-		currentReaderMetadata = attributes;
-		// TODO: move to a reusable method (or use same metadata on both reader and writer side?)
-		currentWriterMetadata.clear();
-		if (currentRelationConfiguration && currentRelationConfiguration->writerMetadata.size()) {
-			if (currentRelationConfiguration->inputAttributesPrepend) add(currentReaderMetadata, currentWriterMetadata);
-			currentWriterMetadata.insert(currentWriterMetadata.end(), currentRelationConfiguration->writerMetadata.begin(), currentRelationConfiguration->writerMetadata.end());
-			if (currentRelationConfiguration->inputAttributesAppend) add(currentReaderMetadata, currentWriterMetadata);
-		} else {
-			add(currentReaderMetadata, currentWriterMetadata);
-		}
-
-		generateVariableMappings();
-
-		if (currentRelationConfiguration && currentRelationConfiguration->debugVariableMapping) debugVariableMapping(name);
-
-		if (!currentRelationConfiguration || !currentRelationConfiguration->drop) relationalWriter->startRelation(name, currentWriterMetadata, true);
-
-		if (currentRelationConfiguration) {
-			// TODO: better variable name, object, function?
-			defineGuileVariable(L"relpipe-relation-name", &name, typeid (name), TypeId::STRING);
-			evalGuileCode(currentRelationConfiguration->guileBeforeRecords);
-		}
-	}
-
-	void attribute(const void* value, const std::type_info& type) override {
-		if (currentRelationConfiguration) {
-			defineGuileVariable(a2v(currentReaderMetadata[currentAttributeIndex].getAttributeName()), value, type, currentReaderMetadata[currentAttributeIndex].getTypeId());
-
-			currentAttributeIndex++;
-
-			// TODO: > 0 ?:
-			if (currentAttributeIndex > 0 && currentAttributeIndex % currentReaderMetadata.size() == 0) {
-				evalGuileCode(currentRelationConfiguration->guileForEach);
-				includeCurrentRecord = scm_to_bool(evalGuileCode(currentRelationConfiguration->guileWhere, SCM_BOOL_T));
-				if (includeCurrentRecord && !currentRelationConfiguration->drop) writeCurrentRecord();
-				includeCurrentRecord = false;
-				writeMoreRecords();
-			}
-
-			currentAttributeIndex = currentAttributeIndex % currentReaderMetadata.size();
-		} else {
-			relationalWriter->writeAttribute(value, type);
-		}
-	}
-
-	void endOfPipe() {
-		if (currentRelationConfiguration) {
-			evalGuileCode(currentRelationConfiguration->guileAfterRecords);
-			writeMoreRecords();
-		}
-	}
-
-};
-
-}
-}
-}