/*
 *  libxio.c
 *
 *  Copyright (C) Lukas Hejtmanek - January 2004
 *
 *  This file is part of transcode, a video stream processing tool
 *
 *  transcode is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2, or (at your option)
 *  any later version.
 *
 *  transcode is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with GNU Make; see the file COPYING.  If not, write to
 *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

#undef PACKAGE
#undef VERSION

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#ifdef HAVE_IBP
#include <lors.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <string.h>
#include <sys/types.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <errno.h>
#include <stdarg.h>

#include "libtc.h"
#include "xio.h"

#define MAX_HANDLES 256

static void * xio_handles[MAX_HANDLES];
static int xio_initialized = 0;
pthread_mutex_t xio_lock;

#ifdef HAVE_IBP
#define IBP_URI "lors://"
#define IBP_URI_LEN 7

#define BLOCK_SIZE_SHIFT 1024

#define LBONE_PORT 6767
#define LORS_BLOCKSIZE 10*1024
#define LORS_DURATION 3600
#define LORS_COPIES 1
#define LORS_THREADS 1
#define LORS_TIMEOUT 100
#define LORS_SERVERS 1
#define LORS_SIZE    10*1024*1024

struct xio_ibp_handle_t {
    LorsDepotPool   *dp;
    LorsExnode  *ex;
    off_t           b_pos;
    off_t           begin;
    off_t       end;
    void        *buffer;
    char            *filename;
    char        *lbone_server;
    int     lbone_port;
    int     lors_blocksize;
    int         lors_duration;
    int     lors_copies;
    int     lors_threads;
    int     lors_timeout;
    int     lors_servers;
    off_t       lors_size;
    int     fill_buffer;
    int     dirty_buffer;
    int         mode;
};

static void *
ibp_open(const char *uri, int mode, int m)
{
    struct xio_ibp_handle_t *handle;
    int ret;

    if(strncmp(uri, IBP_URI, IBP_URI_LEN) != 0) {
        errno = EINVAL;
        return (void *)-1;
    }
    uri += IBP_URI_LEN;

    handle=(struct xio_ibp_handle_t*)calloc(1,
                                 sizeof(struct xio_ibp_handle_t));

    // environment setup
    handle->lbone_server = getenv("LBONE_SERVER");
    if(getenv("LBONE_PORT")) {
        handle->lbone_port = atoi(getenv("LBONE_PORT"));
    } else {
        handle->lbone_port = LBONE_PORT;
    }

    if(getenv("LORS_BLOCKSIZE")) {
        handle->lors_blocksize = atoi(getenv("LORS_BLOCKSIZE"));
    } else {
        if(mode & O_WRONLY || mode & O_CREAT)
            handle->lors_blocksize = LORS_BLOCKSIZE;
        else
            handle->lors_blocksize = 128;
    }

    if(getenv("LORS_DURATION")) {
        handle->lors_duration = atoi(getenv("LORS_DURATION"));
    } else {
        handle->lors_duration = LORS_DURATION;
    }

    if(getenv("LORS_COPIES")) {
        handle->lors_copies = atoi(getenv("LORS_COPIES"));
    } else {
        handle->lors_copies = LORS_COPIES;
    }

    if(getenv("LORS_THREADS")) {
        handle->lors_threads = atoi(getenv("LORS_THREADS"));
    } else {
        handle->lors_threads = LORS_THREADS;
    }

    if(getenv("LORS_TIMEOUT")) {
        handle->lors_timeout = atoi(getenv("LORS_TIMEOUT"));
    } else {
        handle->lors_timeout = LORS_TIMEOUT;
    }

    if(getenv("LORS_SERVERS")) {
        handle->lors_servers = atoi(getenv("LORS_SERVERS"));
    } else {
        handle->lors_servers = LORS_SERVERS;
    }

    if(getenv("LORS_SIZE")) {
                handle->lors_servers = atoi(getenv("LORS_SIZE"));
        } else {
                handle->lors_servers = LORS_SIZE;
        }

    if(*uri != '/') {
        // get LBONE_SERVER from URI
        if(strchr(uri, ':')) {
            // port is defined
            handle->lbone_server = tc_strndup(uri,
                    strchr(uri, ':')-uri);
            uri = (char *)(strchr(uri, ':')+1);
            handle->lbone_port = atoi(uri);
        } else {
            // only host
            handle->lbone_server = tc_strndup(uri,
                    (int)(strchr(uri, '/')-uri));
        }
        uri = (char *)(strchr(uri, '/')+1);
    } else {
        uri += 1;
    }

    if(!strchr(uri, '?')) {
        // only filename
        handle->filename = strdup(uri);
    } else {
        // parse options
        handle->filename = tc_strndup(uri, (int)(strchr(uri, '?')-uri));
        uri = strchr(uri, '?')+1;
        while(uri != (char *)1) {
            if(strncmp(uri, "bs", 2) == 0) {
                handle->lors_blocksize = atoi(&uri[3]);
            } else if(strncmp(uri, "duration", 8) == 0) {
                handle->lors_duration = atoi(&uri[9]);
            } else if(strncmp(uri, "copies", 6) == 0) {
                handle->lors_copies = atoi(&uri[7]);
            } else if(strncmp(uri, "threads", 7) == 0) {
                handle->lors_threads = atoi(&uri[8]);
            } else if(strncmp(uri, "timeout", 7) == 0) {
                handle->lors_timeout = atoi(&uri[8]);
            } else if(strncmp(uri, "servers", 7) == 0) {
                handle->lors_servers = atoi(&uri[8]);
            } else if(strncmp(uri, "size", 4) == 0) {
                handle->lors_size = atoi(&uri[5]);
            }
            uri = strchr(uri, '&') + 1;
        }
    }

    handle->lors_blocksize *= BLOCK_SIZE_SHIFT;

    handle->mode = mode;
    handle->b_pos = 0;
    handle->begin = 0;
    handle->end = 0;
    handle->dirty_buffer = 0;

    if(mode & O_WRONLY || mode & O_CREAT) {
        handle->buffer = malloc(handle->lors_blocksize);
            if(!handle->buffer) {
                    free(handle);
                    errno = EIO;
                    return (void *)-1;
            }
        ret = lorsGetDepotPool(&handle->dp, handle->lbone_server,
                    handle->lbone_port, NULL,
                        handle->lors_servers, NULL,
                    handle->lors_size/(1024*1024)+1,
                    IBP_HARD,
                        handle->lors_duration,
                    handle->lors_threads,
                    handle->lors_timeout,
                    LORS_CHECKDEPOTS);
        if(ret != LORS_SUCCESS) {
            errno = EIO;
            return (void *)-1;
        }
        ret = lorsExnodeCreate(&handle->ex);
        if (ret != LORS_SUCCESS) {
            errno = EIO;
                return (void *)-1;
        }
    }
    if(mode & O_RDONLY || !mode) {
        handle->buffer = malloc(handle->lors_blocksize);
        handle->fill_buffer = 1;
        ret = lorsFileDeserialize(&handle->ex, handle->filename, NULL);
        if(ret != LORS_SUCCESS) {
            errno = EIO;
            return (void *)-1;
        }
        ret = lorsUpdateDepotPool(handle->ex, &handle->dp,
                          handle->lbone_server, 0,
                      NULL, handle->lors_threads,
                      handle->lors_timeout, 0);
        if(ret != LORS_SUCCESS) {
            errno = EIO;
                        return (void *)-1;
                }
    }
    return (void *)handle;
}


static int
ibp_flush(void *handle)
{
    struct xio_ibp_handle_t *hdl = (struct xio_ibp_handle_t *)handle;
    int ret;
    LorsSet *set;

    if(hdl->dirty_buffer == 0) {
        return 0;
    }

    ret = lorsQuery(hdl->ex, &set, hdl->begin, hdl->end,
            LORS_QUERY_REMOVE);
    if(ret != LORS_SUCCESS) {
        errno = EINVAL;
        return -1;
    }

    if(jrb_empty(set->mapping_map)) {
        ret = lorsSetInit(&set, hdl->end/hdl->lors_threads, 1, 0);
                if(ret != LORS_SUCCESS) {
                    errno = EIO;
                    return -1;
            }

        ret = lorsSetStore(set, hdl->dp, hdl->buffer,
                hdl->begin, hdl->end, NULL,
                hdl->lors_threads,
                hdl->lors_timeout, LORS_RETRY_UNTIL_TIMEOUT);

        if(ret != LORS_SUCCESS) {
            lorsSetFree(set,LORS_FREE_MAPPINGS);
            errno = EIO;
            return -1;
        }
    } else {
        set->copies=hdl->lors_copies;
                set->data_blocksize=hdl->end/hdl->lors_threads;
        ret = lorsSetUpdate(set, hdl->dp, hdl->buffer,
                    hdl->begin, hdl->end,
                    hdl->lors_threads,hdl->lors_timeout,
                    LORS_RETRY_UNTIL_TIMEOUT);
                if(ret != LORS_SUCCESS) {
                    lorsSetFree(set,LORS_FREE_MAPPINGS);
                errno=EIO;
                return -1;
                }
    }

    ret = lorsAppendSet(hdl->ex, set);
        if(ret != LORS_SUCCESS) {
            lorsSetFree(set, LORS_FREE_MAPPINGS);
                errno=EIO;
                return -1;
        }

        lorsSetFree(set,0);

    hdl->begin += hdl->b_pos;

    hdl->end = 0;

    ret = lorsFileSerialize(hdl->ex, hdl->filename, 0, 0);

        if(ret != LORS_SUCCESS) {
            perror("file serialize");
    }

    hdl->dirty_buffer = 0;
    return 0;
}

static ssize_t
ibp_write(void *handle, const void *buffer, size_t size)
{
    struct xio_ibp_handle_t *hdl = (struct xio_ibp_handle_t *)handle;

    pthread_testcancel();
    pthread_mutex_lock(&xio_lock);
    pthread_testcancel();
    if(size > hdl->lors_blocksize)
        size = hdl->lors_blocksize;

    if(!hdl || !buffer || hdl->mode == O_RDONLY || !hdl->buffer) {
        errno = EINVAL;
        pthread_mutex_unlock(&xio_lock);
        return -1;
    }

    hdl->dirty_buffer = 1;

    if(hdl->b_pos + size >= hdl->lors_blocksize) {
        if(ibp_flush(handle)) {
            errno = EIO;
            pthread_mutex_unlock(&xio_lock);
            return -1;
        }
        hdl->b_pos = 0;
    }

    memcpy((char *)hdl->buffer + hdl->b_pos, buffer, size);
    hdl->b_pos += size;
    if(hdl->end < hdl->b_pos)
        hdl->end = hdl->b_pos;

    pthread_mutex_unlock(&xio_lock);
    return size;
}

static ssize_t
ibp_read(void *handle, void *buffer, size_t size)
{
    struct xio_ibp_handle_t *hdl = (struct xio_ibp_handle_t *)handle;
    int ret;
    int msize=size;
    LorsSet *set;

    pthread_testcancel();
    pthread_mutex_lock(&xio_lock);
    pthread_testcancel();

    if(hdl->mode == O_WRONLY) {
        errno = EINVAL;
        pthread_mutex_unlock(&xio_lock);
        return -1;
    }

    if(size > hdl->lors_blocksize - hdl->b_pos)
        msize = hdl->lors_blocksize - hdl->b_pos;

    if(hdl->b_pos < hdl->lors_blocksize && !hdl->fill_buffer) {
                memcpy(buffer, hdl->buffer+hdl->b_pos, msize);
                hdl->b_pos += msize;
        pthread_mutex_unlock(&xio_lock);
                return msize;
        }

    hdl->fill_buffer = 0;

    ret = lorsQuery(hdl->ex, &set, hdl->begin + hdl->b_pos,
            hdl->lors_blocksize, 0);
    if(ret != LORS_SUCCESS) {
        pthread_mutex_unlock(&xio_lock);
        return 0;
    }

    ret = lorsSetLoad(set, hdl->buffer, hdl->begin + hdl->b_pos,
            hdl->lors_blocksize, hdl->lors_blocksize,
                              NULL, hdl->lors_threads, hdl->lors_timeout, 0);

    lorsSetFree(set, 0);

    if(ret < 0) {
        errno = EIO;
        pthread_mutex_unlock(&xio_lock);
        return -1;
    }

    hdl->begin += hdl->b_pos;

    if(size > ret)
        size = ret;

    hdl->b_pos = size;
    memcpy(buffer, hdl->buffer, size);
    pthread_mutex_unlock(&xio_lock);
    return size;
}

static off_t
ibp_lseek(void *handle, off_t offs, int mode)
{
    struct xio_ibp_handle_t *hdl = (struct xio_ibp_handle_t *)handle;

    pthread_mutex_lock(&xio_lock);
    pthread_testcancel();
    if(mode == SEEK_SET) {
        if(offs - hdl->begin > hdl->lors_blocksize ||
                offs < hdl->begin) {
            if(ibp_flush(handle)) {
                errno = EIO;
                pthread_mutex_unlock(&xio_lock);
                return -1;
            }
            hdl->fill_buffer = 1;
            hdl->begin = offs;
            hdl->b_pos = 0;
        } else {
            hdl->b_pos = offs - hdl->begin;
        }
    }
    else if(mode == SEEK_CUR) {
        if(hdl->b_pos + offs > hdl->lors_blocksize ||
                hdl->b_pos + offs < 0) {
            if(ibp_flush(handle)) {
                errno = EIO;
                pthread_mutex_unlock(&xio_lock);
                return -1;
            }
            hdl->fill_buffer = 1;
            hdl->begin = hdl->begin + hdl->b_pos + offs;
            hdl->b_pos = 0;
        } else {
            hdl->b_pos += offs;
        }
    } else if(mode == SEEK_END) {
        if(ibp_flush(handle)) {
            errno = EIO;
            pthread_mutex_unlock(&xio_lock);
            return -1;
        }
        hdl->fill_buffer = 1;
        hdl->begin = hdl->ex->logical_length + offs;
        hdl->b_pos = 0;
    } else {
        errno=EINVAL;
        pthread_mutex_unlock(&xio_lock);
                return(-1);
    }

    pthread_mutex_unlock(&xio_lock);
    return hdl->begin + hdl->b_pos;
}

static int
ibp_close(void *handle)
{
    struct xio_ibp_handle_t *hdl = (struct xio_ibp_handle_t *)handle;
    int ret;

    pthread_mutex_lock(&xio_lock);
    pthread_testcancel();
    if(hdl->mode & O_WRONLY || hdl->mode & O_CREAT) {
        if(hdl->dirty_buffer)
            ibp_flush(handle);
        else {
            ret = lorsFileSerialize(hdl->ex, hdl->filename, 0, 0);
                if(ret != LORS_SUCCESS) {
                        perror("file serialize");
                }
        }
    }
    if(hdl->buffer)
        free(hdl->buffer);
    ret = lorsExnodeFree(hdl->ex);
    if(ret != LORS_SUCCESS) {
        perror("exnode free");
    }
    if(!hdl) {
        pthread_mutex_unlock(&xio_lock);
        return 0;
    }
    if(hdl->dp)
        lorsFreeDepotPool(hdl->dp);
    pthread_mutex_unlock(&xio_lock);
    free(hdl);
    return 0;
}

static int
ibp_ftruncate(void *stream, off_t length)
{
    struct xio_ibp_handle_t* hdl = (struct xio_ibp_handle_t*)stream;
    int ret;
    LorsSet *set;

    pthread_mutex_lock(&xio_lock);
    pthread_testcancel();
    ibp_flush(stream);
    hdl->b_pos = 0;
    if(length == hdl->ex->logical_length) {
        pthread_mutex_unlock(&xio_lock);
        return 0;
    }

    ret = lorsQuery(hdl->ex, &set, length,
            hdl->ex->logical_length-length, 0);
        if(ret != LORS_SUCCESS) {
        pthread_mutex_unlock(&xio_lock);
            errno = EINVAL;
            return -1;
    }
    ret = lorsSetTrim(set, length, hdl->ex->logical_length-length,
            1, 20, LORS_TRIM_ALL);
    lorsSetFree(set, 0);
    if(ret != LORS_SUCCESS) {
        pthread_mutex_unlock(&xio_lock);
        errno = EIO;
        return -1;
    }
    pthread_mutex_unlock(&xio_lock);
    return 0;
}

static char *
ibp_lorstoname(char *file_name)
{
    char * uri = file_name;
    if(strncmp(uri, IBP_URI, IBP_URI_LEN) != 0) {
        return strdup(uri);
    }
    uri += IBP_URI_LEN;
    uri = (char *)(strchr(uri, '/')+1);
    if(!strchr(uri, '?')) {
        return strdup(uri);
    }
    return tc_strndup(uri, (int)(strchr(uri, '?')-uri));
}

static int
ibp_stat(const char *file_name, struct stat *buf)
{
    LorsExnode *exnode;
    int ret;
    char *fn;

    fn = ibp_lorstoname((char *)file_name);
    ret = lorsFileDeserialize(&exnode, fn, NULL);
    if(ret!=0) {
                errno=EACCES;
                return -1;
        }
    if(stat(fn, buf) == -1) {
        free(fn);
        return -1;
    }
    buf->st_ino=-1;
        buf->st_dev=-1;
        buf->st_size=exnode->logical_length;
        lorsExnodeFree(exnode);
    free(fn);
    return 0;
}

static int
ibp_lstat(const char *file_name, struct stat *buf)
{
    char *fn = ibp_lorstoname((char *)file_name);
        if(lstat(fn,buf) == -1) {
        free(fn);
                return -1;
        }
    free(fn);
    return 0;
}

static int
ibp_fstat(void *stream, struct stat *buf)
{
    struct xio_ibp_handle_t *hdl = (struct xio_ibp_handle_t *)stream;

    return ibp_stat(hdl->filename,buf);
}

#endif



#define XIO_VALID_FD(fd) \
        ((fd) > 2 && (fd) < MAX_HANDLES)

#define XIO_HAS_HANDLE(fd) \
        (XIO_VALID_FD(fd) && (xio_handles[(fd)] != NULL))

#define XIO_CHECK_INIT \
    if(!xio_initialized) { \
        xio_init(); \
        xio_initialized = 1; \
    }

static void
xio_init(void)
{
    int i;

    for (i = 0; i < MAX_HANDLES; i++) {
        xio_handles[i] = NULL;
    }

    pthread_mutex_init(&xio_lock, NULL);
}

int
xio_open(const char *pathname, int flags, ...)
{
    int i;
    int hid;
    int mode = 0;

    XIO_CHECK_INIT;

    if(flags & O_CREAT) {
        va_list arg;
        va_start(arg, flags);
        mode = va_arg(arg, int);
        va_end(arg);
    }

    pthread_mutex_lock(&xio_lock);
    /* Find free IO handle, skipping stdin, stdout, stderr */
    for(i = 3; xio_handles[i] != NULL && i < MAX_HANDLES; i++) {
        ; /* do nothing in loop body */
    }
    hid = (i == MAX_HANDLES) ?-1 :i;
    pthread_mutex_unlock(&xio_lock);

    if(hid == -1) {
        errno = EIO;
        return -1;
    }

#ifdef HAVE_IBP
    if(strncmp(pathname, IBP_URI, IBP_URI_LEN) == 0) {
        // IBP uri
        xio_handles[hid] = ibp_open(pathname, flags, mode);
        if(!xio_handles[hid]) {
            errno = EIO;
            return -1;
        }
        return hid;
    }
#endif
    return open(pathname, flags, mode);
}

ssize_t
xio_read(int fd, void *buf, size_t count)
{
    XIO_CHECK_INIT;
    
#ifdef HAVE_IBP
    if(XIO_HAS_HANDLE(fd)) {
        return ibp_read(xio_handles[fd], buf, count);
    }
#endif
    return read(fd, buf, count);
}

ssize_t
xio_write(int fd, const void *buf, size_t count)
{
    XIO_CHECK_INIT;
    
#ifdef HAVE_IBP
    if(XIO_HAS_HANDLE(fd)) {
        return ibp_write(xio_handles[fd], buf, count);
    }
#endif
    return write(fd, buf, count);
}

int
xio_ftruncate(int fd, off_t length)
{
    XIO_CHECK_INIT;
    
#ifdef HAVE_IBP
    if(XIO_HAS_HANDLE(fd)) {
        return ibp_ftruncate(xio_handles[fd], length)
    }
#endif
    return ftruncate(fd, length);
}

off_t
xio_lseek(int fd, off_t offset, int whence)
{
    XIO_CHECK_INIT;
    
#ifdef HAVE_IBP
    if(XIO_HAS_HANDLE(fd)) {
        return ibp_lseek(xio_handles[fd], offset, whence);
    }
#endif
    return lseek(fd, offset, whence);
}

int
xio_close(int fd)
{
    XIO_CHECK_INIT;

#ifdef HAVE_IBP
    if(XIO_HAS_HANDLE(fd)) {
        int ret = ibp_close(xio_handles[fd]);
        xio_handles[fd] = NULL;
        return ret;
    }
#endif
    return close(fd);
}

int
xio_stat(const char *file_name, struct stat *buf)
{
    XIO_CHECK_INIT;

#ifdef HAVE_IBP
    if(strncmp(file_name, IBP_URI, IBP_URI_LEN) == 0) {
        return ibp_stat(file_name, buf);
    }
#endif
    return stat(file_name, buf);
}

int
xio_lstat(const char *file_name, struct stat *buf)
{
    XIO_CHECK_INIT;

#ifdef HAVE_IBP
    if(strncmp(file_name, IBP_URI, IBP_URI_LEN) == 0) {
        return ibp_lstat(file_name, buf);
    }
#endif
    return lstat(file_name, buf);
}

int
xio_rename(const char *oldpath, const char *newpath)
{
#ifdef HAVE_IBP
    char *old, *old_p;
    char *newp;
    int ret;

    if(strncmp(IBP_URI, oldpath, IBP_URI_LEN) == 0) {
        old_p = old = strdup(oldpath);
        old = strchr(old + IBP_URI_LEN,'/')+1;
        if(strchr(old, '?')) {
            *(strchr(old, '?')) = 0;
        }

        newp = malloc(strlen(old)+1+4);
        snprintf(newp, strlen(old)+1+4, "%s%s", old, &newpath[strlen(newpath)-4]);
        ret = rename(old, newp);
        free(old_p);
        return ret;
    }
#endif
    return rename(oldpath, newpath);
}

int
xio_fstat(int fd, struct stat *buf)
{
    XIO_CHECK_INIT;

#ifdef HAVE_IBP
    if(XIO_HAS_HANDLE(fd)) {
        return ibp_fstat(xio_handles[fd], buf)
    }
#endif
    return fstat(fd, buf);
}