#include <cstddef>
#include <ostream>
#include <string>
#include <iostream>
#include <fstream>
#include <cstring>

static int get_text(const char *path, std::string &text)
{
	std::ifstream	file(path);

	if (!file.is_open())
	{
		std::cerr << "sed: file error" << std::endl;
		return (1);
	}
	std::getline(file, text, '\0');
	file.close();
	return (0);
}

static std::string	replace_text(const char *text, const char *text_to_replace, const std::string &replacement_text)
{
	size_t		i;
	size_t		len;
	std::string	out;

	len = std::strlen(text_to_replace);
	i = 0;
	while (text[i] != '\0')
	{
		if (len != 0 && std::strncmp(text + i, text_to_replace, len) == 0)
		{
			out += replacement_text;
			i += len;
		}
		else
		{
			out += text[i];
			i++;
		}
	}
	return (out);
}

int main(int ac, char **av)
{
	std::string text;
	std::string replaced;

	if (!(ac >= 4))
	{
		std::cerr << "Sed: missing argument" << std::endl
			<< "syntax: ./sed file text_to_replace replacement_text" << std::endl;
		return (1);
	}
	if (get_text(av[1], text))
		return (2);
	replaced = replace_text(text.c_str(), av[2], av[3]);
	std::ofstream	file((std::string(av[1]) + std::string(".replace")).c_str());
	if (!file.is_open())
	{
		std::cerr << "sed: file error" << std::endl;
		return (1);
	}
	file << replaced << std::endl;
}