#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include <assert.h>
#include "replace.h"

char *__replace(char *str);

int main(int argc, char *argv[])
{
        struct stat buf;
        char *source_string;
        char *target_string;
        int infd;
        int outfd;
        int len;

        if (argc != 3)
        {
                printf("Usage: html2text soruce target\n");
                return 1;
        }

        infd = open(argv[1], O_RDONLY);
        assert(infd >= 0);

        stat(argv[1], &buf);
        len = buf.st_size;

        if (len > 0)
        {
                source_string = (char *)malloc(sizeof(char) * len + 1); // +1은 '\0'을 위한 공간
                read(infd, source_string, len);
                source_string[len] = '\0';

                target_string = __replace(source_string);

                outfd = open(argv[2], O_CREAT|O_WRONLY, 0x666);
                assert(outfd >= 0);

                write(outfd, target_string, strlen(target_string));
                close(outfd);

                free(source_string);
                free(target_string);
        }

        close(infd);
}

char* __replace(char* str)
{
        string rep_str = str;
        __replace_with(rep_str, "&lt;", "<");
        __replace_with(rep_str, "&gt;", ">");
        __replace_with(rep_str, "&amp;", "&");
        __replace_with(rep_str, "&quot;", "\"");
        __replace_with(rep_str, "&reg;", "");
        __replace_with(rep_str, "&copy;", "");
        __replace_with(rep_str, "&ensp;", "");
        __replace_with(rep_str, "&emsp;", "");
        __replace_with(rep_str, "&nbsp;", "");
        __replace_with(rep_str, "&endash;", "");
        __replace_with(rep_str, "&emdash;", "");
        __replace_with(rep_str, "  ", "");
        __replace_with(rep_str, "\n\n", "");
        __replace_with(rep_str, "\n\n", "");

        return strdup(rep_str.c_str());
}

#ifndef __REPLACE_H_
#define __REPLACE_H_

#include <string>

#ifdef __cplusplus
extern "C"
{
#endif

static void __replace_with(string& org, string key, string target)
{
        int start;
        start = 0;
        while(start < org.size())
        {
                if((start = org.find(key, start)) == string::npos)
                        break;
                org.replace(start, key.size(), target);
        }
}

#ifdef __cplusplus
}
#endif

#endif