#include "String.h"

#include <cassert>

String::String()
{
	str[0] = '\0';
}


String::String(char c)
{
	str[0] = c;
	str[1] = '\0';
}

String::String(const char c_arr[])
{
	int i = 0;
	for (i = 0; i < STRING_SIZE; i++)
	{
		if (c_arr[i] == '\0')
			break;
		str[i] = c_arr[i];
		
	}
	str[i] = '\0';
}


int String::length() const
{
	/*
	int len = 0;


	while (str[len] != '\0')
	{
		len++;
	}

	return len;
	*/
	int i;
	for (i = 0; i < STRING_SIZE; i++)
	{
		if (str[i] == '\0')
			break;
	}

	return i;
}

char String::operator[](int index) const // accessor, getter
{
	// if (index>=0 && index<length())
	assert(index >= 0 && index < length());
	
	return str[index];
}

char& String::operator[](int index) // mutator, setter
{
	// if (index>=0 && index<length())
	assert(index >= 0 && index < length());
	return str[index];
}

String& String::operator+=(const String& str2)
{
	int len = length();

	int i=0;
	while (str2.str[i] != '\0')			// bug here: str2[i] --> str2.str[i]
	{
		str[len + i] = str2.str[i];
		i++;
		if (len + i >= capacity())
			break;
	}
	str[len + i] = '\0';

	return *this;
}

bool String::operator==(const String& str2) const
{
	int len1 = length();
	int len2 = str2.length();
	if (len1 != len2)
		return false;
	int i;
	for (i = 0; i < len1; i++)
	{
		if (str[i] != str2.str[i])
			return false;
	}

	return true;
}

// whether current string object is a substring of str2
bool String::operator<=(const String& str2) const
{
	int len1 = length();
	int len2 = str2.length();

	if (len1 >= len2)
		return false;

	for (int i = 0; i <= len2 - len1; i++)
	{
		if (substr(i, i + len1 - 1) == (*this))
			return true;
	}

	return false;
}

// whether current string object is strictly a substring of str2
bool String::operator<(const String& str2) const
{
	return (*this <= str2 && !(*this == str2));
}

String String::substr(int start, int end) const
{
	if (start < 0)
		start = 0;
	if (start > length())
		return String();
	if (start > end)
		return String();
	if (end >= length())
		end = length() - 1;

	String rlt;
	int i;
	for (i = start; i <= end; i++)
	{
		rlt.str[i - start] = str[i];
	}
	rlt.str[i - start] = '\0';

	return rlt;
}

int String::findchar(int start, char c)
{
	if (start < 0)
		start = 0;
	if (start > length() - 1)
		return -1;

	int i;
	int len = length();
	for (i = start; i < len; i++)
	{
		if (str[i] == c)
			return i;
	}

	return -1;
}

std::ostream& operator<<(std::ostream& out, String& s)
{
	out << s.str;
	return out;
}
std::istream& operator>>(std::istream& in, String& s)
{
	char c;
	int i = 0;
	while (!in.eof())
	{
		in >> c;
		s.str[i] = c;
		i++;
	}
	s.str[i] = '\0';

	return in;
}

int main()
{
	String s1('a');
	String s2("abc");

	std::cout << s1 << std::endl;
	std::cout << s2 << std::endl;

	std::cout << s2[1] << std::endl;

	s1 += s2;
	std::cout << s1 << std::endl;

	String s4 = s1.substr(0, 1);
	std::cout << s4 << std::endl;

}