#include <stdlib.h>
#include <stdio.h>
#include <linux/limits.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <dirent.h>
#include <string.h>

#define BASE_DIR         "/tmp/chp"
#define INTERMEDIATE_DIR "/tmp/chp/intermediate"
#define COMPILE_DIR      "/tmp/chp/compiled"

#define BUFFER_SIZE      25565

char *replace_tag(char *str, int pos)
{
	// TODO

	char *new = malloc(strlen(str) + 256);
	memset(new, strlen(str) + 256, sizeof(char));
	
	strncat(new, str, pos);
}

void handle_file(char *filename)
{
	int filename_length = strlen(filename);

	if (strncmp(filename + filename_length - 4, ".chp", 4) != 0)
		return;

	char *intermediate_filename = strdup(filename);
	intermediate_filename[filename_length - 2] = '\0';


	FILE *input = fopen(filename, "r");
	FILE *output = fopen(intermediate_filename, "w");

	char buffer[BUFFER_SIZE], newbuffer[BUFFER_SIZE];
	
	while (fgets(buffer, BUFFER_SIZE, input) != NULL) {
		char *str = buffer, *pos;

		// TODO
		/*while ((pos = strstr(str, "<?c")) != NULL)
			str = replace_tag(str, pos - str);*/

		fputs(newbuffer, output);
	}

	free(intermediate_filename);
}

void read_directory(char *dirname)
{
	DIR *dir = opendir(dirname);
	if (!dir) return;

	struct dirent *entry;
	while ((entry = readdir(dir)) != NULL) {
		if (!strncmp(entry->d_name, ".", 1) || !strncmp(entry->d_name, "..", 2)) continue;

		int pathlength = strlen(dirname) + strlen(entry->d_name) + 2;
		char *pathname = malloc(pathlength);
		snprintf(pathname, pathlength, "%s/%s", dirname, entry->d_name);

		switch (entry->d_type) {
			case DT_REG:
				handle_file(pathname);
				break;
			case DT_DIR:
				read_directory(pathname);
				break;
		}

		free(pathname);
	}
}

int main(void)
{
	puts("Compiling..");

	mkdir(BASE_DIR, 0777);
	mkdir(INTERMEDIATE_DIR, 0777);
	mkdir(COMPILE_DIR, 0777);

	char current_dir[PATH_MAX];
	getcwd(current_dir, sizeof(current_dir));

	read_directory(current_dir);

	puts("Ready");

	return EXIT_SUCCESS;
}