/*
 * Copyright (C) 2009-2012 Geometer Plus <contact@geometerplus.com>
 *
 * 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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 */

#include "SQLiteDataReader.h"

shared_ptr<DBValue> SQLiteDataReader::makeDBValue(sqlite3_stmt *statement, std::size_t column) {
	if (column >= (std::size_t) sqlite3_column_count(statement)) {
		return 0;
	}
	const int type = sqlite3_column_type(statement, column);
	switch (type) {
		case SQLITE_INTEGER: return new DBIntValue(sqlite3_column_int(statement, column));
		case SQLITE_FLOAT:   return new DBRealValue(sqlite3_column_double(statement, column));
		case SQLITE_TEXT:    return new DBTextValue((const char *) sqlite3_column_text(statement, column));
		case SQLITE_NULL:    return DBValue::create(DBValue::DBNULL);
	}
	return 0;
}

SQLiteDataReader::SQLiteDataReader(SQLiteCommand &command) : 
	myCommand(command), 
	myCurrentStatement(0),
	myLocked(true) {
}

SQLiteDataReader::~SQLiteDataReader() {
	close();
}

bool SQLiteDataReader::next() {
	const std::vector<sqlite3_stmt *> &statements = myCommand.statements();
	while (true) {
		int res = sqlite3_step(statements[myCurrentStatement]);
		switch (res) {
		case SQLITE_OK:
			break;
		case SQLITE_ROW:
			return true;
		case SQLITE_DONE:
			if (++myCurrentStatement >= statements.size()) {
				return false;
			}
			break;
		default:
			myCommand.dumpError();
			return false;
		}
	}	
}

bool SQLiteDataReader::reset() {
	return myCommand.resetStatements();
}

void SQLiteDataReader::close() {
	if (myLocked) {
		reset();
		myCommand.unlock();
		myLocked = false;
	}
}

std::size_t SQLiteDataReader::columnsNumber() const {
	sqlite3_stmt *statement = currentStatement();
	return sqlite3_column_count(statement);
}

DBValue::ValueType SQLiteDataReader::type(std::size_t column) const {
	sqlite3_stmt *statement = currentStatement();
	if (column >= (std::size_t) sqlite3_column_count(statement)) {
		return DBValue::DBNULL;
	}
	const int type = sqlite3_column_type(statement, column);
	switch (type) {
	case SQLITE_INTEGER: return DBValue::DBINT;
	case SQLITE_FLOAT:   return DBValue::DBREAL;
	case SQLITE_TEXT:    return DBValue::DBTEXT;
	case SQLITE_NULL:    return DBValue::DBNULL;
	default:
		return DBValue::DBNULL;
	}
}

shared_ptr<DBValue> SQLiteDataReader::value(std::size_t column) const {
	sqlite3_stmt *statement = currentStatement();
	return makeDBValue(statement, column);
}

int SQLiteDataReader::intValue(std::size_t column) const {
	sqlite3_stmt *statement = currentStatement();
	if (column >= (std::size_t)sqlite3_column_count(statement) ||
			sqlite3_column_type(statement, column) != SQLITE_INTEGER) {
		return 0;
	}
	return sqlite3_column_int(statement, column);
}

double SQLiteDataReader::realValue(std::size_t column) const {
	sqlite3_stmt *statement = currentStatement();
	if (column >= (std::size_t)sqlite3_column_count(statement) ||
			sqlite3_column_type(statement, column) != SQLITE_FLOAT) {
		return 0;
	}
	return sqlite3_column_double(statement, column);
}

std::string SQLiteDataReader::textValue(std::size_t column, const std::string &defaultValue) const {
	sqlite3_stmt *statement = currentStatement();
	if (column < (std::size_t)sqlite3_column_count(statement) &&
			sqlite3_column_type(statement, column) == SQLITE_TEXT) {
		const char *result = (const char*)sqlite3_column_text(statement, column);
		if (result != 0) {
			return result;
		}
	}
	return defaultValue;
}