#include "storm/utility/cstring.h"

#include <cstring>

#include "storm/exceptions/WrongFormatException.h"
#include "storm/utility/macros.h"
namespace storm {

namespace utility {

namespace cstring {

/*!
 *	Calls strtol() internally and checks if the new pointer is different
 *	from the original one, i.e. if str != *end. If they are the same, a
 *	storm::exceptions::WrongFormatException will be thrown.
 *	@param str String to parse
 *	@param end New pointer will be written there
 *	@return Result of strtol()
 */
uint_fast64_t checked_strtol(char const* str, char const** end) {
	uint_fast64_t res = strtol(str, const_cast<char**>(end), 10);
	if (str == *end) {
		STORM_LOG_ERROR("Error while parsing integer. Next input token is not a number.");
		STORM_LOG_ERROR("\tUpcoming input is: \"" << std::string(str, 0, 16) << "\"");
		throw storm::exceptions::WrongFormatException("Error while parsing integer. Next input token is not a number.");
	}
	return res;
}

/*!
 *	Calls strtod() internally and checks if the new pointer is different
 *	from the original one, i.e. if str != *end. If they are the same, a
 *	storm::exceptions::WrongFormatException will be thrown.
 *	@param str String to parse
 *	@param end New pointer will be written there
 *	@return Result of strtod()
 */
double checked_strtod(char const* str, char const** end) {
	double res = strtod(str, const_cast<char**>(end));
	if (str == *end) {
		STORM_LOG_ERROR("Error while parsing floating point. Next input token is not a number.");
		STORM_LOG_ERROR("\tUpcoming input is: \"" << std::string(str, 0, 16) << "\"");
		throw storm::exceptions::WrongFormatException("Error while parsing floating point. Next input token is not a number.");
	}
	return res;
}

/*!
 * Skips all numbers, letters and special characters.
 * Returns a pointer to the first char that is a whitespace.
 * @param buf The string buffer to operate on.
 * @return A pointer to the first whitespace character.
 */
char const* skipWord(char const* buf){
	while(!isspace(*buf) && *buf != '\0') buf++;
	return buf;
}

/*!
 *	Skips spaces, tabs, newlines and carriage returns. Returns a pointer
 *	to first char that is not a whitespace.
 *	@param buf The string buffer to operate on.
 *	@return	A pointer to the first non-whitespace character.
 */
char const* trimWhitespaces(char const* buf) {
	while (isspace(*buf)) buf++;
	return buf;
}

/*!
 * @brief Encapsulates the usage of function @strcspn to forward to the end of the line (next char is the newline character).
 */
char const* forwardToLineEnd(char const* buffer) {
	return buffer + strcspn(buffer, "\n\r\0");
}

/*!
 * @brief Encapsulates the usage of function @strchr to forward to the next line
 */
char const* forwardToNextLine(char const* buffer) {
	char const* lineEnd = forwardToLineEnd(buffer);
	while((*lineEnd == '\n') || (*lineEnd == '\r')) lineEnd++;
	return lineEnd;
}

} // namespace cstring

} // namespace utility

} // namespace storm