#include <net/if.h>
#include <sys/ioctl.h>
#include <string.h>
#include <dlfcn.h>
#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <wchar.h>

#include <windows.h>
#include <iphlpapi.h>
#include <setupapi.h>
#include <devguid.h>
#include <pthread.h>

#include "osdep.h"
#include "tap-win32/common.h"

#define BUFSIZE 0x3E8000

struct CV_Header {
        unsigned int TickCount; // GetTickCount() / 1000 at time of packet
        unsigned int Micros;    // Microsecond counter at time of packet
        /* The following might be backwards, unsure */
        int PacketSize;         // Full packet size?
        int SliceSize;          // Truncated packet size?
        int Unknown;            // Not sure what this is.
};

struct CV_Header2 {
        char ErrorFlag;   // ErrorFlag & 1 = CRC error
        char Unknown2[6]; // Unknown
        char Power;       // Power
        char Unknown3[6]; // Unknown
};

struct cstate {
	char		cs_param[256];
	int		cs_ioctls;
	struct ifreq	cs_ifreq;
	char		cs_guid[256];
	HKEY		cs_key;
	int		cs_chan;
	volatile int	cs_restarting;
	void		*cs_lib;
	pthread_mutex_t	cs_mtx;
	int		cs_debug;

	char		(__cdecl *cs_F1)(int Code);
	char		(__cdecl *cs_F2)(void);
	char		(__cdecl *cs_T1)(int Size, unsigned char *Buffer);
	char		(__cdecl *cs_CC)(int Channel);
	char		(__cdecl *cs_S1)(int Channel);
	int		(__cdecl *cs_S5)(unsigned char *Buffer, int Length);
	int		(__cdecl *cs_GN)(wchar_t *);
	int		(*cs_SC)(int band);
} _cs;

static struct cstate *get_cs(void)
{
	return &_cs;
}

static int print_error(char *fmt, ...)
{
	va_list ap;

	va_start(ap, fmt);
	vprintf(fmt, ap);
	va_end(ap);
	printf("\n");

	return -1;
}

static void print_debug(char *fmt, ...)
{
	struct cstate *cs = get_cs();
	va_list ap;

	if (!cs->cs_debug)
		return;

	va_start(ap, fmt);
	vprintf(fmt, ap);
	va_end(ap);
	printf("\n");
}

static int do_init_lib(struct cstate *cs)
{
	/* init */
        if (!cs->cs_F1(BUFSIZE))
		return print_error("F1");
       
       	/* start monitor */
        if (!cs->cs_S1(cs->cs_chan))
		return print_error("S1");

	/* change chan */
	if (!cs->cs_CC(cs->cs_chan))
		return print_error("CC");

	return 0;
}

static int init_lib(struct cstate *cs)
{
	char *lib = "ca2k.dll";
	void *ca2k_dll;

	ca2k_dll = dlopen(lib, RTLD_LAZY);
	if (!ca2k_dll)
		return print_error("dlopen(%s)", lib);
	cs->cs_lib = ca2k_dll;

        // Initialise
        cs->cs_F1 = dlsym(ca2k_dll, "F1");
        // Transmit
        cs->cs_T1 = dlsym(ca2k_dll, "T1");
        // Change monitoring channel
        cs->cs_CC = dlsym(ca2k_dll, "CC");
        // Start monitoring
        cs->cs_S1 = dlsym(ca2k_dll, "S1");
        // Read packets
        cs->cs_S5 = dlsym(ca2k_dll, "S5");
	// Finalize
	cs->cs_F2 = dlsym(ca2k_dll, "F2");
	// Get Adapter Name 
	cs->cs_GN = dlsym(ca2k_dll, "GN");

        if (!(cs->cs_F1 && cs->cs_T1 && cs->cs_CC && cs->cs_S1 && cs->cs_S5
	      && cs->cs_F2 && cs->cs_GN))
		return print_error("Can't find syms");

	return do_init_lib(cs);
}

static int get_name(struct cstate *cs, char *name)
{
	wchar_t wname[1024];
	unsigned int i;

	if (!(cs->cs_GN(wname) & 1))
		return print_error("GN()");

	/* XXX */
	for (i = 0; i < (sizeof(wname)/sizeof(wchar_t)); i++) {
		if (wname[i] == 0)
			break;

		*name++ = (char) ((unsigned char) wname[i]);
	}
	*name = 0;

	return 0;
}

static int get_guid(struct cstate *cs, char *param)
{
	IP_ADAPTER_INFO ai[16];
	DWORD len = sizeof(ai);
	PIP_ADAPTER_INFO p;
	char name[1024];
	int found;

	if (get_name(cs, name) == -1)
		return print_error("get_name()");

	print_debug("Name: %s", name);

	if (GetAdaptersInfo(ai, &len) != ERROR_SUCCESS)
		return print_error("GetAdaptersInfo()");

	p = ai;
	while (p) {
		print_debug("get_guid: name: %s desc: %s",
			    p->AdapterName, p->Description);

		found = (param && strcmp(p->AdapterName, param) == 0)
			|| strstr(p->Description, name);

		/* XXX */
		if (cs->cs_debug) {
			char yea[512];

			printf("Does this look like your card? [y/n]\n");
			yea[0] = 0;
			fgets(yea, sizeof(yea), stdin);
			if (yea[0] == 'y')
				found = 1;
			else
				found = 0;
		}
		
		if (found) {
			snprintf(cs->cs_guid, sizeof(cs->cs_guid)-1, "%s",
				 p->AdapterName);
			return 0;
		}

		p = p->Next;
	}

	return print_error("Adapter not found");
}

static int open_key(struct cstate *cs, char *name)
{
	char key[256];
	DWORD dt, len = sizeof(key);

	/* open key */
	snprintf(key, sizeof(key)-1, "%s\\%s", ADAPTER_KEY, name);
	if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, key, 0, KEY_ALL_ACCESS,
			 &cs->cs_key) != ERROR_SUCCESS)
		return print_error("RegOpenKeyEx()");

	/* check if its our guid */
	if ((RegQueryValueEx(cs->cs_key, "NetCfgInstanceId", NULL, &dt,
	    		     (unsigned char*)key, &len) == ERROR_SUCCESS) 
	     && (dt == REG_SZ) && (strcmp(key, cs->cs_guid) == 0))
		return 1; /* closekey done by cleanup */

	/* nope */
	RegCloseKey(cs->cs_key);
	cs->cs_key = NULL;

	return 0;
}

static int open_conf(struct cstate *cs)
{
        HKEY ak47;
	int rc = -1;
	int i;
	char name[256];
	DWORD len;

	if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, ADAPTER_KEY, 0, KEY_READ, &ak47)
	    != ERROR_SUCCESS)
		return print_error("RegOpenKeyEx()");

	for (i = 0;; i++) {
		len = sizeof(name);
		if (RegEnumKeyEx(ak47, i, name, &len, NULL, NULL, NULL, NULL)
		    != ERROR_SUCCESS)
			break;

		rc = open_key(cs, name);
		if (rc)
			break;
		else
			rc = -1;
	}

	RegCloseKey(ak47);
	return rc;
}

static int check_param(struct cstate *cs, char **p)
{
	char *param = *p;

	/* assume it's ifname */
	if (strncmp(param, "eth", 3) == 0) {
		snprintf(cs->cs_param, sizeof(cs->cs_param), "%s", param);
		snprintf(cs->cs_ifreq.ifr_name,
			 sizeof(cs->cs_ifreq.ifr_name), "%s", cs->cs_param);
		
		cs->cs_ioctls = socket(PF_INET, SOCK_DGRAM, 0);
		if (cs->cs_ioctls == -1) {
			cs->cs_ioctls = 0;
			return print_error("socket()");
		}
	} else if(strcmp(param, "debug") == 0) {
		cs->cs_debug = 1;
		*p = NULL;
	}

	return 0;
}

int cygwin_init(char *param)
{
	struct cstate *cs = get_cs();

	memset(cs, 0, sizeof(*cs));
	cs->cs_chan = 1;

	if (pthread_mutex_init(&cs->cs_mtx, NULL))
		return print_error("pthread_mutex_init()");

	if (param) {
		if (check_param(cs, &param))
			return -1;
	}

	if (init_lib(cs) == -1)
		return print_error("init_lib()");

	if (get_guid(cs, param) == -1)
		return print_error("get_guid()");

	if (open_conf(cs) == -1)
		return print_error("open_conf()");

	return 0;
}

int cygwin_set_chan(int chan)
{
	struct cstate *cs = get_cs();

	if (!cs->cs_CC(chan))
		return -1;

	cs->cs_chan = chan;

	return 0;
}

int cygwin_inject(void *buf, int len, struct tx_info *ti)
{
	struct cstate *cs = get_cs();

	if (ti) {} /* XXX unused */

	if (!cs->cs_T1(len, buf))
		return -1;

	return len;
}

static int read_single_packet(struct cstate *cs, unsigned char *buf, int len,
			      struct rx_info *ri)
{          
        static unsigned char data[BUFSIZE];
        static int totlen = 0;
        static unsigned char *next;
        struct CV_Header *cvh;
        struct CV_Header2 *cvh2;
        unsigned char *hdr;
        int align, plen;
        
        /* read data if necessary */
        if (totlen == 0) {
		/* XXX can't kill iface if we're reading */
		if (pthread_mutex_lock(&cs->cs_mtx))
			return -1;
                totlen = cs->cs_S5(data, sizeof(data));
		if (pthread_mutex_unlock(&cs->cs_mtx))
			return -1;

                if (totlen < 1)
			return -1;

                next = data;
        }

        /* copy packet */
        cvh = (struct CV_Header*) next;
        cvh2 = (struct CV_Header2*) (cvh+1);
        hdr = (unsigned char*) (cvh2+1);
        plen = cvh->SliceSize - sizeof(*cvh2);
        assert(plen > 0);
        if (plen < len)
                len = plen;
        memcpy(buf, hdr, len);

	if (ri)
		ri->ri_power = cvh2->Power;

        /* go to next packet */
        next = hdr + plen;
        align = ((unsigned long)next - (unsigned long)cvh ) % 4;
        if (align)
                align = 4 - align;
        next += align;
        totlen -= sizeof(*cvh) + cvh->SliceSize;
        assert(totlen >= 0);
        if (totlen > 0)
                totlen -= align;
        assert(totlen >= 0);

        return (cvh2->ErrorFlag & 1) ? 0 : len;
}

int cygwin_sniff(void *buf, int len, struct rx_info *ri)
{
	struct cstate *cs = get_cs();
        int rc;
	int tries = 60;

        while ((rc = read_single_packet(cs, buf, len, ri)) == 0);

	if (rc != -1)
		return rc;

	/* check if we're restarting */
	while (cs->cs_restarting && tries--) {
		/* try again */
		if (cs->cs_restarting == 2) {
			cs->cs_restarting = 0;
			return cygwin_sniff(buf, len, ri);
		}

		sleep(1);
	}

        return rc;
}

static int do_get_mac_win(struct cstate *cs, unsigned char *mac)
{
	IP_ADAPTER_INFO ai[16];
	DWORD len = sizeof(ai);
	PIP_ADAPTER_INFO p;

	if (GetAdaptersInfo(ai, &len) != ERROR_SUCCESS)
		return -1;

	p = ai;
	while (p) {
		if (strcmp(cs->cs_guid, p->AdapterName) == 0) {
			memcpy(mac, p->Address, 6);
			return 0;
		}

		p = p->Next;
	}

	return -1;
}

static int do_get_mac_cygwin(struct cstate *cs, unsigned char *mac)
{
	if (ioctl(cs->cs_ioctls, SIOCGIFHWADDR, &cs->cs_ifreq) == -1)
		return -1;

	memcpy(mac, cs->cs_ifreq.ifr_addr.sa_data, 6);

	return 0;
}

int cygwin_get_mac(unsigned char *mac)
{
	struct cstate *cs = get_cs();

	if (cs->cs_ioctls)
		return do_get_mac_cygwin(cs, mac);
	
	return do_get_mac_win(cs, mac);
}

static int is_us2(struct cstate *cs, HDEVINFO *hdi, SP_DEVINFO_DATA *did)
{             
        char buf[256];
        DWORD len = sizeof(buf), dt;
              
        if (cs) {} /* XXX unused */
              
        if (!SetupDiGetDeviceRegistryProperty(*hdi, did, SPDRP_DEVICEDESC, &dt,
                                              (unsigned char*)buf, len, &len))
                return 0;
              
        if (dt != REG_SZ)
                return 0;

	return strstr(buf, "CommView") != NULL;
}

static int reset_state(HDEVINFO *hdi, SP_DEVINFO_DATA *did, DWORD state)
{
        SP_PROPCHANGE_PARAMS parm;
        
        parm.ClassInstallHeader.cbSize = sizeof(parm.ClassInstallHeader);
        parm.ClassInstallHeader.InstallFunction = DIF_PROPERTYCHANGE;
        parm.Scope = DICS_FLAG_GLOBAL;
        parm.StateChange = state;

        if (!SetupDiSetClassInstallParams(*hdi, did, (SP_CLASSINSTALL_HEADER*)
                                          &parm, sizeof(parm)))
                return -1;

        if (!SetupDiCallClassInstaller(DIF_PROPERTYCHANGE, *hdi, did))
                return -1;

        return 0;
}

static int do_reset(HDEVINFO *hdi, SP_DEVINFO_DATA *did)
{
        int rc;

        rc = reset_state(hdi, did, DICS_DISABLE);
        if (rc)
                return rc;

        return reset_state(hdi, did, DICS_ENABLE);
}

static int restart(struct cstate *cs)
{
	int rc;
	
	rc = do_init_lib(cs);

	return rc;
}

static int reset(struct cstate *cs)
{
        HDEVINFO hdi;
        SP_DEVINFO_DATA did;
        int i;
        int rc = -1;

        hdi = SetupDiGetClassDevs(&GUID_DEVCLASS_NET, NULL, NULL,
                          DIGCF_PRESENT);
        if (hdi == INVALID_HANDLE_VALUE)
                return -1;

        /* find device */
        for (i = 0;; i++) {
                did.cbSize = sizeof(did);
                if (!SetupDiEnumDeviceInfo(hdi, i, &did))
                        break;
                
                if (!is_us2(cs, &hdi, &did))
                        continue;

		/* XXX we are blocked on reader.  */
		if (pthread_mutex_lock(&cs->cs_mtx))
			break;
		cs->cs_restarting = 1;

		/* kill lib */
		if (!cs->cs_F2())
			break;

		/* reset NIC */
                rc = do_reset(&hdi, &did);
                if (rc) 
                        break;

		sleep(1); /* XXX seems necessary */

		/* reinit lib */
                rc = restart(cs);
		cs->cs_restarting = 2;
		
		/* done */
		if (pthread_mutex_unlock(&cs->cs_mtx))
			break;

                break;
        }
        
        SetupDiDestroyDeviceInfoList(hdi);

        return rc;
}

int cygwin_set_mac(unsigned char *mac)
{
	struct cstate *cs = get_cs();
        char str[2*6+1];
	char strold[sizeof(str)];
        int i;
	char *key = "NetworkAddress";
	DWORD dt, len = sizeof(strold);
        
	/* convert */
        str[0] = 0;
        for (i = 0; i < 6; i++) {
                char tmp[3];
                
                if (sprintf(tmp, "%.2X", *mac++) != 2)
			return -1;
                strcat(str, tmp);
        }

	/* check old */
	if ((RegQueryValueEx(cs->cs_key, key, NULL, &dt, (unsigned char*)
	    strold, &len) == ERROR_SUCCESS) && (dt == REG_SZ)) {
		if (strcmp(str, strold) == 0)
			return 0;
	}
       
	/* set */
	if (RegSetValueEx(cs->cs_key, key, 0, REG_SZ,
			(unsigned char *)str, strlen(str)+1) != ERROR_SUCCESS)
                return -1;
              
        if (reset(cs) == -1)
                return -1;

        return 0;
}

void cygwin_close(void)
{
	struct cstate *cs = get_cs();

	if (cs->cs_ioctls)
		close(cs->cs_ioctls);

	if (cs->cs_key)
		RegCloseKey(cs->cs_key);

	if (cs->cs_lib) {
		cs->cs_F2();
		dlclose(cs->cs_lib);
	}
}