#include <stdio.h>
#include <string.h>

#ifdef WIN32
#include <windows.h>
#else
#include <sys/stat.h>
#include <sys/types.h>
#endif

#include <zip.h>

#define BUF_SIZE    128

#ifndef MAX_PATH
#define MAX_PATH    2048
#endif

const char pathsep = 
#ifdef WIN32
    '\\';
#else
    '/';
#endif


int makedir(const char *dir)
{
#ifdef WIN32
    return mkdir(dir);
#else
    return mkdir(dir, 0755);
#endif
}

void gen_full_filename(const char *basedir, const char *file, char *dest, size_t destsize)
{
int i;
#ifdef WIN32
char *fix;
#endif

    if(basedir == NULL)
        strncpy(dest, file, destsize);
    else if(file == NULL)
        strncpy(dest, basedir, destsize);
    else {
        if(basedir[strlen(basedir)-1] == '/' || basedir[strlen(basedir)-1] == '\\')
            snprintf(dest, destsize, "%s%s", basedir, file);
        else
            snprintf(dest, destsize, "%s%c%s", basedir, pathsep, file);
    }

#ifdef WIN32
    fix = strchr(dest, '/');
    while(fix != NULL) {
        *fix = '\\';
        fix = strchr(dest, '/');
    }
#endif

}

void ensure_directory(const char *base, const char *filename)
{
char *onedir;
char *fulldir;
char *tmp;

    if(filename == NULL || base == NULL) return;
    if(strlen(filename) == 0) return;

    onedir = (char *)malloc((strlen(filename)+1)*sizeof(char));
    fulldir = (char *)malloc((strlen(filename)+strlen(base)+2)*sizeof(char));
    
    strcpy(onedir, filename);
    tmp = onedir;
    
    tmp = strchr(onedir, pathsep);    
#ifdef WIN32
    if(tmp == NULL)
        tmp = strchr(onedir, '/');
#endif
    
    while(tmp != NULL) {
    
        *tmp = '\0';
        
        gen_full_filename(base, onedir, fulldir, (strlen(filename)+strlen(base)+2));
        makedir(fulldir);
    
        *tmp = pathsep;
        tmp++;
#ifdef WIN32
        if(strchr(tmp, pathsep)  == NULL)
            tmp = strchr(tmp, '/');
        else
            tmp = strchr(tmp, pathsep);
#else
        tmp = strchr(tmp, pathsep); 
#endif
    }
    
    free(onedir);
    free(fulldir);
}

int unzip_file(const char *filename, const char *directory, const char *index_of_files_file)
{
struct zip *za;
struct zip_file *zf;
struct zip_stat sb;

char buf[BUF_SIZE];
int err, i;
size_t this_read, total_read;

char fullfile[MAX_PATH];
FILE *fp;
FILE *fp_index;

    za = zip_open(filename, 0, &err);
    if (za == NULL) {
        return -1;
    }
    
    if(index_of_files_file != NULL) 
        fp_index = fopen(index_of_files_file, "w");
    else
        fp_index = NULL;

    for(i=0; i < zip_get_num_entries(za,0); i++) {
        if (zip_stat_index(za, i, 0, &sb) == 0) {
            gen_full_filename(directory, sb.name, fullfile, MAX_PATH);
            
            if(fullfile[strlen(fullfile)-1] == pathsep) {
            
                makedir(fullfile);
            
            } else {
            
                ensure_directory(directory, sb.name);
            
                zf = zip_fopen_index(za, i, 0);
                fp = fopen(fullfile, "wb");
                if(zf != NULL && fp != NULL) {
                
                    total_read = 0;
                    while(total_read < sb.size) {
                        this_read = zip_fread(zf, buf, BUF_SIZE);
                        fwrite(buf, sizeof(char), this_read, fp);
                        total_read += this_read;
                    }
                
                    if(fp_index != NULL)
                        fprintf(fp_index, "%s\n", fullfile);
                }
                
                if(zf != NULL)
                    zip_fclose(zf);
                    
                if(fp != NULL)
                    fclose(fp);
            }   
                
        }
    }
    
    zip_close(za);
    
    if(fp_index != NULL)
        fclose(fp_index);
    
    return 1;
}