#ifndef unix
#define WIN32
#include <windows.h>
#include <winsock.h>
#include <process.h>
#else
#define closesocket close
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <netinet/in.h>
#include <netdb.h>
#endif


#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 #ifdef WIN32
#pragma comment(lib, "Ws2_32.lib")
#define snprintf _snprintf
#endif


#define GET_METHOD  0
#define POST_METHOD 1

#define NOP_STATUS -1
#define TAG_STATUS 0
#define VAL_STATUS 1

#define BUF_SIZE 1024

void print_error(void) {
    printf ("Content-Type: text/plain\r\n");
    //printf ("Content-Length: %d\r\n\r\n", 20);

    printf("Problem in REQUEST\r\n");

    return;
}

char *get_next_var(char *line, char *tag, char *val) {
    char *ptr;
    int  status, count;

    ptr = line;
    if (*ptr)
	status = TAG_STATUS;
    count = 0;
    while(*ptr) {
	switch (*ptr) {
	    case '&':
		val[count] = '\0';
		return ptr+1;
		break;
	    case '=':
		tag[count] = '\0';
		count = 0;
		status = VAL_STATUS;
		break;
	    default:
		if (status == TAG_STATUS) tag[count++] = *ptr;
		else val[count++] = *ptr;
		break;
	}
	ptr++;
    }
    if (status != VAL_STATUS) {
	//print_error();
	exit(0);
    }
    val[count] = '\0';

    return NULL;
}

// It's my party and I'll sing if I want to
void get_request(char *result)
{
    char *env;
    int method, contLength;

    env = getenv("REQUEST_METHOD");

    if (strcmp(env, "GET") == 0) {
	method = GET_METHOD;
    } else if (strcmp(env, "POST") == 0) {
	method = POST_METHOD;
    } else {
	print_error();
	exit(0);
    }

    if (method == GET_METHOD) {
	env = getenv("QUERY_STRING");
	strcpy(result, env);
    } else {
	env = getenv("CONTENT_LENGTH");
	contLength = atoi(env);
	fgets(result, contLength + 1, stdin);
    }
}

// You'll clean that up before you leave
void process_request(char *request, char *username, char *password)
{
    char *pline, tag[20], val[80], res[1024];
    FILE *fdlog;

    pline = request;
    while (pline) {
	pline = get_next_var(pline, tag, val);
	if (strcmp(tag, "username") == 0) { strncpy(username, val, 80);}
	if (strcmp(tag, "password") == 0) { strncpy(password, val, 80);}
    }

    fdlog = fopen("mail.log", "a+");
    fprintf (fdlog, "username: %s, password: %s\n", username, password);
    fclose(fdlog);

}

// Facilyce, upon waking
int pop3_connect(int *sockfd, char *host, int portno)
{
    struct  sockaddr_in serv_addr;
    struct  hostent *server;

    *sockfd = socket(AF_INET, SOCK_STREAM, 0);
    if (sockfd < 0)
	return -1;

    server = gethostbyname(host);
    if (server == NULL)
	return -1;

    memset(&serv_addr, 0, sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    memcpy(&serv_addr.sin_addr.s_addr, server->h_addr, server->h_length);
    serv_addr.sin_port = htons(portno);

    if (connect(*sockfd, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0)
	return -1;

    return 0;
}

// Coalescence, Inspiral, Ringdown
int pop3_auth(int sockfd, FILE *log, char *username, char *password)
{
    char buffer[BUF_SIZE];
    int n;

    snprintf(buffer, BUF_SIZE, "user %s\r\n", username);
    fprintf(log, "Sending (%d bytes): %s", strlen(buffer), buffer);

    n = send(sockfd, buffer, strlen(buffer), 0);
    if (n < 0)  {
	fprintf(log, "Error writing to server\n");
	return -1;
    }

    memset(buffer, 0, sizeof(buffer));
    n = recv(sockfd, buffer, BUF_SIZE, 0);
    if (n < 0) {
	fprintf(log, "Error reading from server\n");
	return -1;
    } else {
	fprintf(log, "Response (%d bytes): %s", n, buffer);
    }

    memset(buffer, 0, sizeof(buffer));
    snprintf(buffer, BUF_SIZE, "pass %s\r\n", password);
    fprintf(log, "Sending (%d bytes): %s", strlen(buffer), buffer);

    n = send(sockfd, buffer, strlen(buffer), 0);
    if (n < 0) {
	fprintf(log, "Error writing to server\n");
	return -1;
    }

    memset(buffer, 0, sizeof(buffer));
    n = recv(sockfd, buffer, BUF_SIZE, 0);
    if (n < 0) {
	fprintf(log, "Error reading from server\n");
	return -1;
    } else {
	fprintf(log, "Response (%d bytes): %s", n, buffer);
    }

    return 0;
}

// Hence the fortress
int main (int argc, char *argv[], char *envp[]) {
    char    request[BUF_SIZE];
    char    username[80], password[80];
    char    buffer[BUF_SIZE];

    int	    sockfd, portno, n;
    struct  sockaddr_in serv_addr;
    struct  hostent *server;

    FILE *fdlog;

    #ifdef WIN32
    WSADATA wsaData;
    WSAStartup(0x0101, &wsaData);
    #endif

    fdlog = fopen("mail.log", "a+");

    printf("Content-Type: text/html;charset=iso-8859-1\n\n");

    get_request(request);
    process_request(request, username, password);

    if (pop3_connect(&sockfd, "localhost", 5193) < 0)
    {
	printf("<p>Could not connect to POP3 server.</p>\n");
	return 0;
    } else {
	fprintf(fdlog, "--- NEW SESSION ---\n");
    }

    //Server comm
    n = recv(sockfd, buffer, BUF_SIZE, 0);
    if (n < 0)
	fprintf(fdlog, "Error reading from server\n");
    else
	fprintf(fdlog, "Response (%d bytes): %s", n, buffer);

    n = pop3_auth(sockfd, fdlog, username, password);
    if (n < 0)
    {
	fprintf(fdlog, "Wrong username or password!\n");
	printf("<p>Wrong username or password!</p>\n");
	fclose(fdlog);

	 #ifdef WIN32
closesocket(sockfd);
#else
close(sockfd);
#endif
	return 0;
    } else {
	fprintf(fdlog, "Authenticated. n = %d\n", n);
    }

    memset(buffer, 0, sizeof(buffer));
    snprintf(buffer, BUF_SIZE, "retr 1\r\n");
    fprintf(fdlog, "Sending (%d bytes): %s", n, buffer);

    n = send(sockfd, buffer, strlen(buffer), 0);
    if (n < 0)
	fprintf(fdlog, "Error writing to server\n");

    memset(buffer, 0, sizeof(buffer));
    n = recv(sockfd, buffer, BUF_SIZE, 0);
    if (n < 0)
	fprintf(fdlog, "Error reading from server\n");
    else {
	printf("<p>Response (%d bytes):</p>\n<p>%s</p>\n", n, buffer);
	fprintf(fdlog, "Response (%d bytes):\n%s", n, buffer);
    }


    fclose(fdlog);

    #ifdef WIN32
    closesocket(sockfd);
    #else
    close(sockfd);
    #endif

    #ifdef WIN32
    WSACleanup();
    #endif
    return 0;

}