#include "String.h"
#include <cstring>
#include <cstdlib>

String::String(const char* str)
	: str(strdup(str))
	, len(strlen(str))
{
}

String::String(const String& other)
	: str(strdup(other.str))
	, len(other.len)
{
}

const String& String::operator=(const String& other)
{
	if ( this != &other )
	{
		free(str);
		str = strdup(other.str);
		len = other.len;
	}
	return *this;
}


String::~String()
{
	free(str);
}

String operator+(const String& s1, const String& s2)
{
	String::length_t result_length = s1.len + s2.len;
	String result(result_length + 1);
	strcpy(result.str, s1.str);
	strcpy(result.str + s1.len, s2.str);
	result.len = result_length;
	return result;
}

String String::operator+(char ch) const
{
	length_t result_length = len + 1;
	String result(result_length + 1);
	strcpy(result.str, str);
	result.str[len] = ch;
	result.str[result_length] = '\0';
	result.len = result_length;
	return result;
}

String::String(length_t capacity)
	: str( (char*) malloc(capacity * sizeof(char)) )
	, len(0)
{
	*str = '\0';
}

String String::operator()(length_t pos, length_t len) const
{
	len = len > 0 ? len : this->len - pos;
	String result(len);
	strncpy(result.str, str, len);
	result.len = len;
	return result;
}

std::ostream& operator<<(std::ostream& output, const String& str)
{
	return output << str.c_str();
}