//#define CURL_STATICLIB

#include <stdlib.h>

#include <memory.h>

#include <curl/curl.h>

#ifdef USE_LIBXML

#include <libxml/parser.h>

#include <libxml/xpath.h>

#include <libxml/xpathInternals.h>

#endif

#define HEX_DIGITS "0123456789ABCDEF"

#define IS_QUOTED(x) (*x == '%' && strchr(HEX_DIGITS, *(x+1)) && strchr(HEX_DIGITS, *(x+2)))

#define WATCH_URL_BASE "http://www.nicovideo.jp/watch/"

typedef struct {

char* data; // response data from server

size_t size; // response size of data

} MEMFILE;

MEMFILE*

memfopen() {

MEMFILE* mf = (MEMFILE*) malloc(sizeof(MEMFILE));

mf->data = NULL;

mf->size = 0;

return mf;

}

void

memfclose(MEMFILE* mf) {

if (mf->data) free(mf->data);

free(mf);

}

size_t

memfwrite(char* ptr, size_t size, size_t nmemb, void* stream) {

MEMFILE* mf = (MEMFILE*) stream;

int block = size * nmemb;

if (!mf->data)

mf->data = (char*) malloc(block);

else

mf->data = (char*) realloc(mf->data, mf->size + block);

if (mf->data) {

memcpy(mf->data + mf->size, ptr, block);

mf->size += block;

}

return block;

}

char*

memfstrdup(MEMFILE* mf) {

char* buf = malloc(mf->size + 1);

memcpy(buf, mf->data, mf->size);

buf[mf->size] = 0;

return buf;

}

int

progress(void *clientp, double dltotal, double dlnow, double ultotal, double ulnow) {

double val;

if (dltotal == 0) dltotal = 1.0;

val = dlnow / dltotal * 100;

printf("\r[%s] %3.0f%% ", (char*) clientp, val);

fflush(stdout);

return 0;

}

int

main(int argc, char* argv[]) {

CURL* curl = NULL;

CURLcode res;

int status = 0;

char error[CURL_ERROR_SIZE];

char fname[256];

char line[256];

char cookie[2048];

char query[2048];

char* buf = NULL;

char* ptr = NULL;

char* tmp = NULL;

char* id;

FILE* fp = NULL;

MEMFILE* mf; // mem file

MEMFILE* hf; // mem file for header

// usage

if (argc != 2) {

fputs("usage: nicodown [video_id]\n", stderr);

goto leave;

}

if (!(ptr = getenv("HOME"))) {

#ifdef _WIN32

if (!(ptr = getenv("USERPROFILE"))) {

fprintf(stderr, "failed to get HOME directory\n");

goto leave;

}

#else

fprintf(stderr, "failed to get HOME directory\n");

goto leave;

#endif

}

sprintf(fname, "%s/.nicodownrc", ptr);

fp = fopen(fname, "r");

if (!fp || !fgets(line, sizeof(line), fp)) {

if (fp) fclose(fp);

fprintf(stderr, "failed to read ~/.nicodownrc\n");

goto leave;

}

fclose(fp);

tmp = strpbrk(line, "\r\n");

if (tmp) *tmp = 0;

ptr = strchr(line, ':');

if (!ptr) {

fprintf(stderr, "failed to parse ~/.nicodownrc\n");

goto leave;

}

*ptr++ = 0;

id = argv[1];

if (!strncmp(id, WATCH_URL_BASE, strlen(WATCH_URL_BASE))) {

id += strlen(WATCH_URL_BASE);

}

sprintf(query, "mail_tel=%s&password=%s&next_url=/watch/%s", line, ptr, id);

// default filename

sprintf(fname, "%s.flv", id);

curl = curl_easy_init();

curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0);

curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1);

curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, error);

curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, memfwrite);

// login

mf = memfopen();

hf = memfopen();

curl_easy_setopt(curl, CURLOPT_URL, "https://secure.nicovideo.jp/secure/login?site=niconico");

curl_easy_setopt(curl, CURLOPT_POST, 1);

curl_easy_setopt(curl, CURLOPT_POSTFIELDS, query);

curl_easy_setopt(curl, CURLOPT_WRITEDATA, mf);

curl_easy_setopt(curl, CURLOPT_HEADERDATA, hf);

curl_easy_setopt(curl, CURLOPT_HEADERFUNCTION, memfwrite);

res = curl_easy_perform(curl);

if (res != CURLE_OK) {

fputs(error, stderr);

memfclose(mf);

memfclose(hf);

goto leave;

}

// parse cookie

memset(cookie, 0, sizeof(cookie));

buf = memfstrdup(hf);

tmp = buf;

while (tmp = strstr(tmp, "Set-Cookie: ")) {

ptr = tmp;

tmp = strpbrk(ptr, "\r\n;");

if (tmp) *tmp = 0;

strcpy(cookie, ptr + 12);

if (strncmp(cookie, "user_session=user", 17) == 0) {

curl_easy_setopt(curl, CURLOPT_COOKIE, cookie);

break;

}

tmp++;

}

free(buf);

memfclose(mf);

memfclose(hf);

mf = memfopen();

hf = memfopen();

curl_easy_setopt(curl, CURLOPT_WRITEDATA, mf);

curl_easy_setopt(curl, CURLOPT_HEADERDATA, hf);

// redirect

sprintf(query, "http://www.nicovideo.jp/watch/%s", id);

curl_easy_setopt(curl, CURLOPT_URL, query);

curl_easy_setopt(curl, CURLOPT_POST, 0);

res = curl_easy_perform(curl);

if (res != CURLE_OK) {

fputs(error, stderr);

memfclose(mf);

memfclose(hf);

goto leave;

}

// parse cookie

buf = memfstrdup(hf);

ptr = NULL;

tmp = buf;

while (tmp = strstr(tmp, "Set-Cookie: ")) {

ptr = tmp + 12;

tmp = strpbrk(ptr, "\r\n;");

if (tmp) *tmp = 0;

strcat(cookie, ";");

strcat(cookie, ptr);

tmp++;

}

curl_easy_setopt(curl, CURLOPT_COOKIE, cookie);

free(buf);

// parse response body

buf = memfstrdup(mf);

if (buf && strstr(buf, "id=\"login_bar\"")) {

free(buf);

fprintf(stderr, "failed to login\n");

memfclose(mf);

memfclose(hf);

goto leave;

}

free(buf);

memfclose(hf);

memfclose(mf);

curl_easy_setopt(curl, CURLOPT_POSTFIELDS, NULL);

curl_easy_setopt(curl, CURLOPT_HEADERDATA, NULL);

curl_easy_setopt(curl, CURLOPT_HEADERFUNCTION, NULL);

curl_easy_setopt(curl, CURLOPT_WRITEDATA, NULL);

curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, NULL);

// get video query, and get filename

sprintf(query, "http://www.nicovideo.jp/api/getthumbinfo?v=%s", id);

mf = memfopen();

curl_easy_setopt(curl, CURLOPT_URL, query);

curl_easy_setopt(curl, CURLOPT_POST, 0);

curl_easy_setopt(curl, CURLOPT_WRITEDATA, mf);

curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, memfwrite);

res = curl_easy_perform(curl);

if (res != CURLE_OK) {

fputs(error, stderr);

memfclose(mf);

goto leave;

}

#ifdef USE_LIBXML

// parse title node

{

xmlDocPtr doc = NULL;

xmlXPathContextPtr xpathctx;

xmlXPathObjectPtr xpathobj;

doc = xmlParseMemory(mf->data, mf->size);

xpathctx = doc ? xmlXPathNewContext(doc) : NULL;

xpathobj = xpathctx ? xmlXPathEvalExpression((xmlChar*) "//title", xpathctx) : NULL;

if (xpathobj) {

int n;

xmlNodeSetPtr nodes = xpathobj->nodesetval;

for(n = 0; nodes && n < xmlXPathNodeSetGetLength(nodes); n++) {

xmlNodePtr node = nodes->nodeTab[n];

if(node->type != XML_ATTRIBUTE_NODE && node->type != XML_ELEMENT_NODE && node->type != XML_CDATA_SECTION_NODE) continue;

if (node->type == XML_CDATA_SECTION_NODE)

sprintf(fname, "%s.flv", (char*) node->content);

else

if (node->children)

sprintf(fname, "%s.flv", (char*) node->children->content);

break;

}

}

if (xpathobj ) xmlXPathFreeObject(xpathobj);

if (xpathctx) xmlXPathFreeContext(xpathctx);

if (doc) xmlFreeDoc(doc);

}

#else

buf = memfstrdup(mf);

ptr = buf ? strstr(buf, "<title>") : NULL;

if (ptr) {

ptr += 7;

tmp = strstr(ptr, "</title>");

if (*tmp) {

*tmp = 0;

sprintf(fname, "%s.flv", ptr);

}

}

if (buf) free(buf);

#endif

memfclose(mf);

#ifdef _WIN32

{

UINT codePage;

size_t wcssize;

wchar_t* wcsstr;

size_t mbssize;

char* mbsstr;

codePage = CP_UTF8;

wcssize = MultiByteToWideChar(codePage, 0, fname, -1, NULL, 0);

wcsstr = (wchar_t*) malloc(sizeof(wchar_t) * (wcssize + 1));

wcssize = MultiByteToWideChar(codePage, 0, fname, -1, wcsstr, wcssize + 1);

wcsstr[wcssize] = 0;

codePage = GetACP();

mbssize = WideCharToMultiByte(codePage, 0, (LPCWSTR) wcsstr,-1,NULL,0,NULL,NULL);

mbsstr = (char*) malloc(mbssize+1);

mbssize = WideCharToMultiByte(codePage, 0, (LPCWSTR) wcsstr, -1, mbsstr, mbssize, NULL, NULL);

mbsstr[mbssize] = 0;

strcpy(fname, mbsstr);

free(mbsstr);

free(wcsstr);

}

#endif

// get video query

sprintf(query, "http://flapi.nicovideo.jp/api/getflv?v=%s", id);

mf = memfopen();

curl_easy_setopt(curl, CURLOPT_URL, query);

curl_easy_setopt(curl, CURLOPT_POST, 0);

curl_easy_setopt(curl, CURLOPT_WRITEDATA, mf);

curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, memfwrite);

res = curl_easy_perform(curl);

if (res != CURLE_OK) {

fputs(error, stderr);

memfclose(mf);

goto leave;

}

buf = memfstrdup(mf);

ptr = strstr(buf, "url=");

if (!ptr) {

if (buf) free(buf);

fprintf(stderr, "failed to get video info\n");

memfclose(mf);

goto leave;

}

tmp = strstr(ptr, "&");

if (tmp) *tmp = 0;

tmp = ptr;

while(*tmp) {

if (IS_QUOTED(tmp)) {

unsigned int num = 0;

sscanf(tmp+1, "%02x", &num);

*tmp = (char)num;

strcpy(tmp + 1, tmp + 3);

}

tmp++;

}

strcpy(query, ptr + 4);

printf("URL: %s\n", query);

free(buf);

memfclose(mf);

// sanitize filename

ptr = fname;

while (*ptr) {

if (strchr("\\/|:<>\"?*", *ptr)) *ptr = '_';

ptr++;

}

// download video

fp = fopen(fname, "wb");

if (!fp) {

fprintf(stderr, "failed to open file: %s\n", fname);

goto leave;

}

curl_easy_setopt(curl, CURLOPT_URL, query);

curl_easy_setopt(curl, CURLOPT_POST, 0);

curl_easy_setopt(curl, CURLOPT_WRITEDATA, fp);

curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, fwrite);

curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 0);

curl_easy_setopt(curl, CURLOPT_PROGRESSFUNCTION, progress);

curl_easy_setopt(curl, CURLOPT_PROGRESSDATA, (void*)fname);

curl_easy_setopt(curl, CURLOPT_BUFFERSIZE, BUFSIZ);

/* curl_easy_setopt(curl, CURLOPT_VERBOSE, 1); */

res = curl_easy_perform(curl);

fclose(fp);

if (res != CURLE_OK) {

fputs(error, stderr);

goto leave;

}

leave:

if (curl) curl_easy_cleanup(curl);

printf("\n");

return 0;

}