#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <dirent.h>
#include <ctype.h>
#include <time.h>
#include <sys/stat.h>
#include "http.h"
#include "../defs.h"

#define SERVER_NAME "ubermicro_httpd"
#define SERVER_URL "http://www.puyan.org"
#define PROTOCOL "HTTP/1.1"
#define RFC1123FMT "%a, %d %b %Y %H:%M:%S GMT"

#ifdef _WIN32
#define S_ISDIR(a) (a & S_IFDIR) 
char lower(const char a);
int strcasecmp(const char *s1, const char *s2);
#endif

static void file_details( char* dir, char* name , FILE *socket_file);
static void send_error( int status, char* title, char* extra_header, char* text, FILE *socket_file );
static void send_headers( int status, char* title, char* extra_header, char* mime_type, off_t length, time_t mod, FILE *socket_file );
static char* get_mime_type( char* name );
static void strdecode( char* to, char* from );
static int hexit( char c );
static void strencode( char* to, size_t tosize, const char* from );

int parse_request(char *request, http_request *package) {
    if ( sscanf(request, "%[^ ] %[^ ] %[^ ]", package->method, package->path, package->protocol ) != 3 ) {
        return EXIT_FAILURE;
    } else {
        return EXIT_SUCCESS;
    }
    return EXIT_FAILURE; // Never Reached
}

void http_proto(int socket, char *request) {
    char idx[2000], location[2000];
    char *method, *path, *protocol;
    char* file;
    size_t len;
    int ich;
    struct stat sb;
    FILE* fp;
    FILE* socket_file;
    struct dirent **dl;
    int i, n;
    char *brkt;
    char *true_request;
    http_request request_package;

    VPRINTF(("\n\nStart http proc\n"));

    VPRINTF(("Full Request:\n%s\n", request));

    true_request=strtok_r(request,"\r", &brkt); 
 
    VPRINTF(("Request size: %d\n", strlen(request))); 
    VPRINTF(("Small Request: \n%s\n", true_request));
    VPRINTF(("1 error on line %d\n", __LINE__));
  
    socket_file = fdopen(socket, "w");
    fflush( socket_file );  //FIXME: May not be necessary, nothing written yet

    if(strlen(request) >= BUFFERSIZE) {
        send_error( 403, "Bad Request", (char*) 0, "No request found." , socket_file );
        goto complete;
    } 
 
    if (EXIT_FAILURE == parse_request(request, &request_package)) {
        send_error( 400, "Bad Request", (char*) 0, "Can't parse request." , socket_file );
        goto complete;
    } else {
        method   = request_package.method;
        path     = request_package.path;
        protocol = request_package.protocol;
    }

    VPRINTF(("Method: %s\n", method));
    VPRINTF(("Path: %s\n", path));
    VPRINTF(("Protocol: %s\n", protocol));
    VPRINTF(("2 error on line %d\n", __LINE__));
     
    if ( strcasecmp( method, "get" ) != 0 ) {
        send_error( 501, "Not Implemented", (char*) 0, "That method is not implemented." , socket_file );
        goto complete;
    }
    
    VPRINTF(("3 error on line %d\n", __LINE__));
    
    if ( path[0] != '/' ) {
        send_error( 400, "Bad Request", (char*) 0, "Bad filename." , socket_file );
        goto complete;
    }

    file = &(path[1]);
    strdecode( file, file );
  
    if ( file[0] == '\0' ) {
        file = "./";
    }
  
    len = strlen( file );

    VPRINTF(("4 error on line %d\n", __LINE__));

    if (   file[0] == '/' 
        || strcmp( file, ".." ) == 0 
        || strncmp( file, "../", 3 ) == 0 
        || strstr( file, "/../" ) != (char*) 0 
        || strcmp( &(file[len-3]), "/.." ) == 0 )
    {
        send_error( 400, "Bad Request", (char*) 0, "Illegal filename." , socket_file );
        goto complete;
    }
   
    if ( stat( file, &sb ) < 0 ) {
        send_error( 404, "Not Found", (char*) 0, "File not found." , socket_file );
        goto complete;
    }

    if ( S_ISDIR( sb.st_mode ) ) {
        if ( file[len-1] != '/' ) {
            snprintf(location, sizeof(location), "Location: %s/", path );            
            send_error( 302, "Found", location, "Directories must end with a slash." , socket_file );
            goto complete;
        }
        
        snprintf( idx, sizeof(idx), "%sindex.html", file );
    
        if ( stat( idx, &sb ) >= 0 )
        {
            file = idx;
            goto do_file; //asshole
        }
        
        /* IMPORTANT */
        send_headers( 200, "Ok", (char*) 0, "text/html", -1, sb.st_mtime , socket_file ); 
        
        fprintf(socket_file, 
                "<html><head><title>Index of %s</title></head>\n<body bgcolor=\"lightblue\"><h4>Index of %s</h4>\n<pre>\n", 
                file, file 
               );

        n = scandir( file, &dl, NULL, alphasort ); /* IMPORTANT */
        
        if ( n < 0 ) {
              perror( "scandir" );
        } else {
            for ( i = 0; i < n; ++i ) {
                /* IMPORTANT */
                file_details( file, dl[i]->d_name, socket_file );
                free(dl[i]);         
                /* the guy that wrote this was a n00b */
            }
           free(dl);                /* Must kill this guy */
        }
    

        fprintf(socket_file,  
            "</pre>\n<hr>\n<address><a href=\"%s\">%s</a></address>\n</body></html>\n", 
            SERVER_URL, SERVER_NAME 
           );
    } else {
        do_file:
        fp = fopen( file, "r" );
    
        if ( fp == (FILE*) 0 ) {
            send_error( 403, "Forbidden", (char*) 0, "File is protected.", socket_file );
            goto complete;
        }
    
        /* IMPORTANT */
        send_headers( 200, "Ok", (char*) 0, get_mime_type( file ), sb.st_size, sb.st_mtime , socket_file );

        while (fp && ( ich = getc( fp ) ) != EOF ) {
            fprintf(socket_file,"%c", ich );
        }

        if (fp) fclose(fp);
    }

    complete: //because this guy wrote terrible code, goto is necessary

    fflush( socket_file ); 

    fclose(socket_file);  
}


static void file_details( char* dir, char* name, FILE *socket_file )
{
    static char encoded_name[1000];
    static char path[2000];
    struct stat sb;
    char timestr[16];

    strencode( encoded_name, sizeof(encoded_name), name );
    snprintf( path, sizeof(path), "%s/%s", dir, name );
  
    #ifdef _WIN32
    if ( stat( path, &sb ) < 0 ) {
    #else
    if ( lstat( path, &sb ) < 0 ) {
    #endif
    fprintf(socket_file, "<a href=\"%s\">%-32.32s</a>    ???\n", encoded_name, name );
    } else {
        strftime(timestr, sizeof(timestr), 
                 "%d%b%Y %H:%M", localtime( &sb.st_mtime ) 
                );
        fprintf(socket_file, 
                "<a href=\"%s\">%-32.32s</a>    %15s %14lld\n", encoded_name, 
                name, timestr, (int64_t) sb.st_size 
               );
    }
}


static void send_error( int status, char* title, char* extra_header, char* text, FILE *socket_file )
{
    send_headers( status, title, extra_header, "text/html", -1, -1, socket_file );
    
    fprintf(socket_file,  
            "<html><head><title>%d %s</title></head>\n<body bgcolor=\"#cc9999\"><h4>%d %s</h4>\n", 
            status, title, status, title 
           );
    
    fprintf(socket_file, "%s\n", text );
    fprintf(socket_file, "<hr>\n<address><a href=\"%s\">%s</a></address>\n", SERVER_URL, SERVER_NAME);
    //fprintf(socket_file, "<img src=\"/pwner.jpg\">\n"); 
    fprintf(socket_file, "</body></html>\n");
    
    fflush( socket_file );  //flush socket
}


static void send_headers( int status, char* title, char* extra_header, char* mime_type, off_t length, time_t mod , FILE *socket_file)
{
    time_t now;
    char timebuf[100];

    fprintf(socket_file, "%s %d %s\015\012", PROTOCOL, status, title );
    fprintf(socket_file, "Server: %s\015\012", SERVER_NAME );
    
    now = time( (time_t*) 0 );
    
    strftime( timebuf, sizeof(timebuf), RFC1123FMT, gmtime( &now ) );
    fprintf(socket_file, "Date: %s\015\012", timebuf );
    
    if ( extra_header != (char*) 0 ) {
        fprintf(socket_file, "%s\015\012", extra_header );
    }
    if ( mime_type != (char*) 0 ) {
        fprintf(socket_file, "Content-Type: %s\015\012", mime_type );
    }
    if ( length >= 0 ) {
        fprintf(socket_file, "Content-Length: %lld\015\012", (int64_t) length );
    }
    if ( mod != (time_t) -1 )
    {
        strftime( timebuf, sizeof(timebuf), RFC1123FMT, gmtime( &mod ) );
        fprintf(socket_file, "Last-Modified: %s\015\012", timebuf );
    }
    fprintf(socket_file, "Connection: close\015\012" );
    fprintf(socket_file, "\015\012" );
}


static char* get_mime_type( char* name )
{
    char* dot;

    dot = strrchr( name, '.' );
    
    if ( dot == (char*) 0 )
        return "text/plain; charset=iso-8859-1";
    
    if ( strcmp( dot, ".html" ) == 0 || strcmp( dot, ".htm" ) == 0 )
        return "text/html; charset=iso-8859-1";
    
    if ( strcmp( dot, ".jpg" ) == 0 || strcmp( dot, ".jpeg" ) == 0 )
        return "image/jpeg";
    
    if ( strcmp( dot, ".gif" ) == 0 )
        return "image/gif";
    
    if ( strcmp( dot, ".png" ) == 0 )
        return "image/png";
    
    if ( strcmp( dot, ".css" ) == 0 )
        return "text/css";
    
    if ( strcmp( dot, ".au" ) == 0 )
        return "audio/basic";
    
    if ( strcmp( dot, ".wav" ) == 0 )
        return "audio/wav";
    
    if ( strcmp( dot, ".avi" ) == 0 )
        return "video/x-msvideo";
    
    if ( strcmp( dot, ".mov" ) == 0 || strcmp( dot, ".qt" ) == 0 )
        return "video/quicktime";
    
    if ( strcmp( dot, ".mpeg" ) == 0 || strcmp( dot, ".mpe" ) == 0 )
        return "video/mpeg";
    
    if ( strcmp( dot, ".vrml" ) == 0 || strcmp( dot, ".wrl" ) == 0 )
        return "model/vrml";
    
    if ( strcmp( dot, ".midi" ) == 0 || strcmp( dot, ".mid" ) == 0 )
        return "audio/midi";
    
    if ( strcmp( dot, ".mp3" ) == 0 )
        return "audio/mpeg";
    
    if ( strcmp( dot, ".m4a" ) == 0 )
        return "audio/mp4";
    
    if ( strcmp( dot, ".pdf" ) == 0 )
        return "application/pdf";
    
    if ( strcmp( dot, ".ogg" ) == 0 )
        return "application/ogg";
    
    if ( strcmp( dot, ".pac" ) == 0 )
        return "application/x-ns-proxy-autoconfig";
    
    return "text/plain; charset=iso-8859-1";
}


static void strdecode( char* to, char* from )
{
  for ( ; *from != '\0'; ++to, ++from )
  {
  if ( from[0] == '%' && isxdigit( from[1] ) && isxdigit( from[2] ) )
  {
  *to = hexit( from[1] ) * 16 + hexit( from[2] );
  from += 2;
  }
  else
  *to = *from;
  }
  *to = '\0';
}


static int hexit( char c )
{
    if ( c >= '0' && c <= '9' )
        return c - '0';
    
    if ( c >= 'a' && c <= 'f' )
        return c - 'a' + 10;
    
    if ( c >= 'A' && c <= 'F' )
        return c - 'A' + 10;
    
    //default
    return 0;    /* shouldn't happen, we're guarded by isxdigit() */
}


static void strencode( char* to, size_t tosize, const char* from )
{
    int tolen;

    for ( tolen = 0; *from != '\0' && tolen + 4 < tosize; ++from )
    {
        if ( isalnum(*from) || strchr( "/_.-~", *from ) != (char*) 0 )
        {
            *to = *from;
            ++to;
            ++tolen;
        } else {
            sprintf( to, "%%%02x", (int) *from & 0xff );
            to += 3;
            tolen += 3;
        }
    }

    *to = '\0';
}

#ifdef _WIN32

char lower(const char a) {
    if (!isalpha(a)) return a;

    if (!(a < 'z' && a > 'a')) {
        return a+32;
    } else {
        return a;
    }
}

/* strcasecmp is not ANSI */
int strcasecmp(const char *s1, const char *s2){
    size_t i;
    
    for(i=0;; i++){
        if(!(lower(*(s1+i)) == lower(*(s2+i)) ) ) {
            return *(s1+i) - *(s2+i);
        }
        if(*(s1+i) == '\0'){
            return 0;
        }
    }

    return 0;
}

#endif