/*
 * (C)opyright MMIV-MMVI Anselm R. Garbe <garbeam at gmail dot com>
 * See LICENSE file for license details.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <unistd.h>

#include "cext.h"
#include "ixp.h"


int
ixp_client_do_fcall(IXPClient * c)
{
	static unsigned char msg[IXP_MAX_MSG];
    unsigned int msize = ixp_fcall_to_msg(&c->fcall, msg, IXP_MAX_MSG);
    c->errstr = 0;
    if(ixp_send_message(c->fd, msg, msize, &c->errstr) != msize)
        return -1;
    if(!ixp_recv_message(c->fd, msg, IXP_MAX_MSG, &c->errstr))
        return -1;
    if(!(msize = ixp_msg_to_fcall(msg, IXP_MAX_MSG, &c->fcall))) {
        c->errstr = "received bad message";
        return -1;
    }
    if(c->fcall.id == RERROR) {
        c->errstr = c->fcall.errstr;
        return -1;
    }
    return 0;
}

int
ixp_client_init(IXPClient *c, char *sockfile, unsigned int rootfid)
{
    if((c->fd = ixp_connect_sock(sockfile)) < 0) {
        c->errstr = "cannot connect server";
        return -1;
    }
    /* version */
    c->fcall.id = TVERSION;
    c->fcall.tag = IXP_NOTAG;
    c->fcall.maxmsg = IXP_MAX_MSG;
    cext_strlcpy(c->fcall.version, IXP_VERSION, sizeof(c->fcall.version));
    if(ixp_client_do_fcall(c) == -1) {
		fprintf(stderr, "error: %s\n", c->fcall.errstr);
        ixp_client_deinit(c);
        return -1;
    }
    if(strncmp(c->fcall.version, IXP_VERSION, strlen(IXP_VERSION))) {
		fprintf(stderr, "error: %s\n", c->fcall.errstr);
        c->errstr = "9P versions differ";
        ixp_client_deinit(c);
        return -1;           /* we cannot handle this version */
    }
    c->root_fid = rootfid;

    /* attach */
    c->fcall.id = TATTACH;
    c->fcall.tag = IXP_NOTAG;
    c->fcall.fid = c->root_fid;
    c->fcall.afid = IXP_NOFID;
    cext_strlcpy(c->fcall.uname, getenv("USER"), sizeof(c->fcall.uname));
    c->fcall.aname[0] = 0;
    if(ixp_client_do_fcall(c) == -1) {
		fprintf(stderr, "error: %s\n", c->fcall.errstr);
        ixp_client_deinit(c);
        return -1;
    }
    c->root_qid = c->fcall.qid;
    return 0;
}

int
ixp_client_remove(IXPClient * c, unsigned int newfid, char *filepath)
{
    if(ixp_client_walk(c, newfid, filepath) == -1)
        return -1;
    /* remove */
    c->fcall.id = TREMOVE;
    c->fcall.tag = IXP_NOTAG;
    c->fcall.fid = newfid;
    return ixp_client_do_fcall(c);
}

int
ixp_client_create(IXPClient * c, unsigned int dirfid, char *name,
                  unsigned int perm, unsigned char mode)
{
    /* create */
    c->fcall.id = TCREATE;
    c->fcall.tag = IXP_NOTAG;
    c->fcall.fid = dirfid;
    cext_strlcpy(c->fcall.name, name, sizeof(c->fcall.name));
    c->fcall.perm = perm;
    c->fcall.mode = mode;
    return ixp_client_do_fcall(c);
}

int
ixp_client_walk(IXPClient * c, unsigned int newfid, char *filepath)
{
	unsigned int i;
	char *wname[IXP_MAX_WELEM];
    /* walk */
    c->fcall.id = TWALK;
    c->fcall.fid = c->root_fid;
    c->fcall.newfid = newfid;
    if(filepath) {
        cext_strlcpy(c->fcall.name, filepath, sizeof(c->fcall.name));
        c->fcall.nwname =
            cext_tokenize(wname, IXP_MAX_WELEM, c->fcall.name, '/');
		for(i = 0; i < c->fcall.nwname; i++)
			cext_strlcpy(c->fcall.wname[i], wname[i], sizeof(c->fcall.wname[i]));
    }
    return ixp_client_do_fcall(c);
}

int
ixp_client_open(IXPClient * c, unsigned int newfid, char *filepath,
                unsigned char mode)
{
    if(ixp_client_walk(c, newfid, filepath) == -1)
        return -1;

    /* open */
    c->fcall.id = TOPEN;
    c->fcall.tag = IXP_NOTAG;
    c->fcall.fid = newfid;
    c->fcall.mode = mode;
    return ixp_client_do_fcall(c);
}

int
ixp_client_read(IXPClient * c, unsigned int fid, unsigned long long offset,
                void *result, unsigned int res_len)
{
    unsigned int bytes = c->fcall.iounit;

    /* read */
    c->fcall.id = TREAD;
    c->fcall.tag = IXP_NOTAG;
    c->fcall.fid = fid;
    c->fcall.offset = offset;
    c->fcall.count = res_len < bytes ? res_len : bytes;
    if(ixp_client_do_fcall(c) == -1)
        return -1;
    memcpy(result, c->fcall.data, c->fcall.count);
    return c->fcall.count;
}

int
ixp_client_write(IXPClient * c, unsigned int fid,
                 unsigned long long offset, unsigned int count,
                 unsigned char *data)
{
    if(count > c->fcall.iounit)
	{
        c->errstr = "iounit exceeded";
        return -1;
    }
    /* write */
    c->fcall.id = TWRITE;
    c->fcall.tag = IXP_NOTAG;
    c->fcall.fid = fid;
    c->fcall.offset = offset;
    c->fcall.count = count;
    memcpy(c->fcall.data, data, count);
    if(ixp_client_do_fcall(c) == -1)
        return -1;
    return c->fcall.count;
}

int
ixp_client_close(IXPClient * c, unsigned int fid)
{
    /* clunk */
    c->fcall.id = TCLUNK;
    c->fcall.tag = IXP_NOTAG;
    c->fcall.fid = fid;
    return ixp_client_do_fcall(c);
}

void
ixp_client_deinit(IXPClient * c)
{
    /* session finished, now shutdown */
    if(c->fd) {
        shutdown(c->fd, SHUT_RDWR);
        close(c->fd);
    }
}