/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
 * vim:expandtab:shiftwidth=8:tabstop=8:
 */
/******************************************************************************\
*                                                                              *
*        Copyright (c) 2003, The Regents of the University of California       *
*      See the file COPYRIGHT for a complete copyright notice and license.     *
*                                                                              *
* Copyright (C) 2018 Intel Corporation
*
* GOVERNMENT LICENSE RIGHTS-OPEN SOURCE SOFTWARE
* The Government's rights to use, modify, reproduce, release, perform, display,
* or disclose this software are subject to the terms of the Apache License as
* provided in Contract No. 8F-30005.
* Any reproduction of computer software, computer software documentation, or
* portions thereof marked with this legend must also reproduce the markings.
********************************************************************************
*
* Implement of abstract I/O interface for DFS.
*
\******************************************************************************/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <string.h>
#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <dirent.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <libgen.h>

#include <gurt/common.h>
#include <daos_types.h>
#include <daos_api.h>
#include <daos_fs.h>

#include "ior.h"
#include "iordef.h"
#include "aiori.h"
#include "utilities.h"

dfs_t *dfs;
daos_handle_t poh, coh;

/************************** O P T I O N S *****************************/
struct dfs_options{
        char * pool;
        char * svcl;
        char * group;
        char * cont;
};

static struct dfs_options o = {
        .pool = NULL,
        .svcl = NULL,
        .group = NULL,
        .cont = NULL,
};

static option_help options [] = {
      {0, "dfs.pool", "DAOS pool uuid", OPTION_REQUIRED_ARGUMENT, 's', & o.pool},
      {0, "dfs.svcl", "DAOS pool SVCL", OPTION_REQUIRED_ARGUMENT, 's', & o.svcl},
      {0, "dfs.group", "DAOS server group", OPTION_OPTIONAL_ARGUMENT, 's', & o.group},
      {0, "dfs.cont", "DFS container uuid", OPTION_REQUIRED_ARGUMENT, 's', & o.cont},
      LAST_OPTION
};

/**************************** P R O T O T Y P E S *****************************/
static void *DFS_Create(char *, IOR_param_t *);
static void *DFS_Open(char *, IOR_param_t *);
static IOR_offset_t DFS_Xfer(int, void *, IOR_size_t *,
                             IOR_offset_t, IOR_param_t *);
static void DFS_Close(void *, IOR_param_t *);
static void DFS_Delete(char *, IOR_param_t *);
static char* DFS_GetVersion();
static void DFS_Fsync(void *, IOR_param_t *);
static IOR_offset_t DFS_GetFileSize(IOR_param_t *, MPI_Comm, char *);
static int DFS_Statfs (const char *, ior_aiori_statfs_t *, IOR_param_t *);
static int DFS_Stat (const char *, struct stat *, IOR_param_t *);
static int DFS_Mkdir (const char *, mode_t, IOR_param_t *);
static int DFS_Rmdir (const char *, IOR_param_t *);
static int DFS_Access (const char *, int, IOR_param_t *);
static void DFS_Init();
static void DFS_Finalize();
static option_help * DFS_options();

/************************** D E C L A R A T I O N S ***************************/

ior_aiori_t dfs_aiori = {
        .name		= "DFS",
        .create		= DFS_Create,
        .open		= DFS_Open,
        .xfer		= DFS_Xfer,
        .close		= DFS_Close,
        .delete		= DFS_Delete,
        .get_version	= DFS_GetVersion,
        .fsync		= DFS_Fsync,
        .get_file_size	= DFS_GetFileSize,
        .statfs		= DFS_Statfs,
        .mkdir		= DFS_Mkdir,
        .rmdir		= DFS_Rmdir,
        .access		= DFS_Access,
        .stat		= DFS_Stat,
        .initialize	= DFS_Init,
        .finalize	= DFS_Finalize,
        .get_options	= DFS_options,
};

/***************************** F U N C T I O N S ******************************/

/* For DAOS methods. */
#define DCHECK(rc, format, ...)                                         \
do {                                                                    \
        int _rc = (rc);                                                 \
                                                                        \
        if (_rc < 0) {                                                  \
                fprintf(stderr, "ERROR (%s:%d): %d: %d: "               \
                        format"\n", __FILE__, __LINE__, rank, _rc,      \
                        ##__VA_ARGS__);                                 \
                fflush(stderr);                                         \
                exit(-1);                                       	\
        }                                                               \
} while (0)

#define DERR(rc, format, ...)                                           \
do {                                                                    \
        int _rc = (rc);                                                 \
                                                                        \
        if (_rc < 0) {                                                  \
                fprintf(stderr, "ERROR (%s:%d): %d: %d: "               \
                        format"\n", __FILE__, __LINE__, rank, _rc,      \
                        ##__VA_ARGS__);                                 \
                fflush(stderr);                                         \
                goto out;                                               \
        }                                                               \
} while (0)

static int
parse_filename(const char *path, char **_obj_name, char **_cont_name)
{
	char *f1 = NULL;
	char *f2 = NULL;
	char *fname = NULL;
	char *cont_name = NULL;
	int rc = 0;

	if (path == NULL || _obj_name == NULL || _cont_name == NULL)
		return -EINVAL;

	if (strcmp(path, "/") == 0) {
		*_cont_name = strdup("/");
		if (*_cont_name == NULL)
			return -ENOMEM;
		*_obj_name = NULL;
		return 0;
	}

	f1 = strdup(path);
	if (f1 == NULL) {
                rc = -ENOMEM;
                goto out;
        }

	f2 = strdup(path);
	if (f2 == NULL) {
                rc = -ENOMEM;
                goto out;
        }

	fname = basename(f1);
	cont_name = dirname(f2);

	if (cont_name[0] == '.' || cont_name[0] != '/') {
		char cwd[1024];

		if (getcwd(cwd, 1024) == NULL) {
                        rc = -ENOMEM;
                        goto out;
                }

		if (strcmp(cont_name, ".") == 0) {
			cont_name = strdup(cwd);
			if (cont_name == NULL) {
                                rc = -ENOMEM;
                                goto out;
                        }
		} else {
			char *new_dir = calloc(strlen(cwd) + strlen(cont_name)
					       + 1, sizeof(char));
			if (new_dir == NULL) {
                                rc = -ENOMEM;
                                goto out;
                        }

			strcpy(new_dir, cwd);
			if (cont_name[0] == '.') {
				strcat(new_dir, &cont_name[1]);
			} else {
				strcat(new_dir, "/");
				strcat(new_dir, cont_name);
			}
			cont_name = new_dir;
		}
		*_cont_name = cont_name;
	} else {
		*_cont_name = strdup(cont_name);
		if (*_cont_name == NULL) {
                        rc = -ENOMEM;
                        goto out;
                }
	}

	*_obj_name = strdup(fname);
	if (*_obj_name == NULL) {
		free(*_cont_name);
		*_cont_name = NULL;
                rc = -ENOMEM;
                goto out;
	}

out:
	if (f1)
		free(f1);
	if (f2)
		free(f2);
	return rc;
}

static option_help * DFS_options(){
  return options;
}

static void
DFS_Init() {
	uuid_t			pool_uuid, co_uuid;
	daos_pool_info_t	pool_info;
	daos_cont_info_t	co_info;
	d_rank_list_t		*svcl = NULL;
        bool			cont_created = false;
	int			rc;

        if (o.pool == NULL || o.svcl == NULL || o.cont == NULL)
                ERR("Invalid pool or container options\n");

	rc = uuid_parse(o.pool, pool_uuid);
        DCHECK(rc, "Failed to parse 'Pool uuid': %s", o.pool);

	rc = uuid_parse(o.cont, co_uuid);
        DCHECK(rc, "Failed to parse 'Cont uuid': %s", o.cont);

	svcl = daos_rank_list_parse(o.svcl, ":");
	if (svcl == NULL)
                ERR("Failed to allocate svcl");

        if (verbose >= VERBOSE_1) {
                printf("Pool uuid = %s, SVCL = %s\n", o.pool, o.svcl);
                printf("DFS Container namespace uuid = %s\n", o.cont);
        }

	rc = daos_init();
        DCHECK(rc, "Failed to initialize daos");

	/** Connect to DAOS pool */
	rc = daos_pool_connect(pool_uuid, o.group, svcl, DAOS_PC_RW, &poh,
                               &pool_info, NULL);
        DCHECK(rc, "Failed to connect to pool");
        d_rank_list_free(svcl);
	rc = daos_cont_open(poh, co_uuid, DAOS_COO_RW, &coh, &co_info, NULL);
	/* If NOEXIST we create it */
	if (rc == -DER_NONEXIST) {
                if (verbose >= VERBOSE_1)
                        printf("Creating DFS Container ...\n");
		rc = daos_cont_create(poh, co_uuid, NULL, NULL);
		if (rc == 0) {
			cont_created = true;
			rc = daos_cont_open(poh, co_uuid, DAOS_COO_RW, &coh,
					    &co_info, NULL);
		}
	}
        DCHECK(rc, "Failed to create container");

	rc = dfs_mount(poh, coh, O_RDWR, &dfs);
        DCHECK(rc, "Failed to mount DFS namespace");
}

static void
DFS_Finalize()
{
        int rc;

	rc = dfs_umount(dfs);
        DCHECK(rc, "Failed to umount DFS namespace");

	rc = daos_cont_close(coh, NULL);
        DCHECK(rc, "Failed to close container");

        daos_pool_disconnect(poh, NULL);
        DCHECK(rc, "Failed to disconnect from pool");

	rc = daos_fini();
        DCHECK(rc, "Failed to finalize DAOS");
}

/*
 * Creat and open a file through the DFS interface.
 */
static void *
DFS_Create(char *testFileName, IOR_param_t *param)
{
	char *name = NULL, *dir_name = NULL;
	dfs_obj_t *obj = NULL, *parent = NULL;
	mode_t pmode, mode;
        int fd_oflag = 0;
	int rc;

        assert(param);

        fd_oflag |= O_CREAT | O_RDWR;
	mode = S_IFREG | param->mode;

	rc = parse_filename(testFileName, &name, &dir_name);
        DERR(rc, "Failed to parse path %s", testFileName);

	assert(dir_name);
	assert(name);

	rc = dfs_lookup(dfs, dir_name, O_RDWR, &parent, &pmode);
        DERR(rc, "dfs_lookup() of %s Failed", dir_name);

	rc = dfs_open(dfs, parent, name, mode, fd_oflag, DAOS_OC_LARGE_RW,
                      0, NULL, &obj);
        DERR(rc, "dfs_open() of %s Failed", name);

out:
	if (name)
		free(name);
	if (dir_name)
		free(dir_name);
	if (parent)
		dfs_release(parent);

        return ((void *)obj);
}

/*
 * Open a file through the DFS interface.
 */
static void *
DFS_Open(char *testFileName, IOR_param_t *param)
{
	char *name = NULL, *dir_name = NULL;
	dfs_obj_t *obj = NULL, *parent = NULL;
	mode_t pmode, mode;
	int rc;
        int fd_oflag = 0;

        fd_oflag |= O_RDWR;
	mode = S_IFREG | param->mode;

	rc = parse_filename(testFileName, &name, &dir_name);
        DERR(rc, "Failed to parse path %s", testFileName);

	assert(dir_name);
	assert(name);

	rc = dfs_lookup(dfs, dir_name, O_RDWR, &parent, &pmode);
        DERR(rc, "dfs_lookup() of %s Failed", dir_name);

	rc = dfs_open(dfs, parent, name, mode, fd_oflag, 0, 0, NULL, &obj);
        DERR(rc, "dfs_open() of %s Failed", name);

out:
	if (name)
		free(name);
	if (dir_name)
		free(dir_name);
	if (parent)
		dfs_release(parent);

        return ((void *)obj);
}

/*
 * Write or read access to file using the DFS interface.
 */
static IOR_offset_t
DFS_Xfer(int access, void *file, IOR_size_t *buffer, IOR_offset_t length,
         IOR_param_t *param)
{
        int xferRetries = 0;
        long long remaining = (long long)length;
        char *ptr = (char *)buffer;
        daos_size_t ret;
        int rc;
	dfs_obj_t *obj;

        obj = (dfs_obj_t *)file;

        while (remaining > 0) {
                d_iov_t iov;
                d_sg_list_t sgl;

                /** set memory location */
                sgl.sg_nr = 1;
                sgl.sg_nr_out = 0;
                d_iov_set(&iov, (void *)ptr, remaining);
                sgl.sg_iovs = &iov;

                /* write/read file */
                if (access == WRITE) {
                        rc = dfs_write(dfs, obj, sgl, param->offset);
                        if (rc) {
                                fprintf(stderr, "dfs_write() failed (%d)", rc);
                                return -1;
                        }
                        ret = remaining;
                } else {
                        rc = dfs_read(dfs, obj, sgl, param->offset, &ret);
                        if (rc || ret == 0)
                                fprintf(stderr, "dfs_read() failed(%d)", rc);
                }

                if (ret < remaining) {
                        if (param->singleXferAttempt == TRUE)
                                exit(-1);
                        if (xferRetries > MAX_RETRY)
                                ERR("too many retries -- aborting");
                }

                assert(ret >= 0);
                assert(ret <= remaining);
                remaining -= ret;
                ptr += ret;
                xferRetries++;
        }

        return (length);
}

/*
 * Perform fsync().
 */
static void
DFS_Fsync(void *fd, IOR_param_t * param)
{
	dfs_sync(dfs);
        return;
}

/*
 * Close a file through the DFS interface.
 */
static void
DFS_Close(void *fd, IOR_param_t * param)
{
        dfs_release((dfs_obj_t *)fd);
}

/*
 * Delete a file through the DFS interface.
 */
static void
DFS_Delete(char *testFileName, IOR_param_t * param)
{
	char *name = NULL, *dir_name = NULL;
	dfs_obj_t *parent = NULL;
	mode_t pmode;
	int rc;

	rc = parse_filename(testFileName, &name, &dir_name);
        DERR(rc, "Failed to parse path %s", testFileName);

	assert(dir_name);
	assert(name);

	rc = dfs_lookup(dfs, dir_name, O_RDWR, &parent, &pmode);
        DERR(rc, "dfs_lookup() of %s Failed", dir_name);

	rc = dfs_remove(dfs, parent, name, false);
        DERR(rc, "dfs_remove() of %s Failed", name);

out:
	if (name)
		free(name);
	if (dir_name)
		free(dir_name);
	if (parent)
		dfs_release(parent);
}

static char* DFS_GetVersion()
{
	static char ver[1024] = {};

	sprintf(ver, "%s", "DAOS");
	return ver;
}

/*
 * Use DFS stat() to return aggregate file size.
 */
static IOR_offset_t
DFS_GetFileSize(IOR_param_t * test, MPI_Comm comm, char *testFileName)
{
        dfs_obj_t *obj;
        daos_size_t fsize, tmpMin, tmpMax, tmpSum;
        int rc;

	rc = dfs_lookup(dfs, testFileName, O_RDONLY, &obj, NULL);
        if (rc) {
                fprintf(stderr, "dfs_lookup() of %s Failed (%d)", testFileName, rc);
                return -1;
        }

        rc = dfs_get_size(dfs, obj, &fsize);
        if (rc)
                return -1;

        dfs_release(obj);

        if (test->filePerProc == TRUE) {
                MPI_CHECK(MPI_Allreduce(&fsize, &tmpSum, 1,
                                        MPI_LONG_LONG_INT, MPI_SUM, comm),
                          "cannot total data moved");
                fsize = tmpSum;
        } else {
                MPI_CHECK(MPI_Allreduce(&fsize, &tmpMin, 1,
                                        MPI_LONG_LONG_INT, MPI_MIN, comm),
                          "cannot total data moved");
                MPI_CHECK(MPI_Allreduce(&fsize, &tmpMax, 1,
                                        MPI_LONG_LONG_INT, MPI_MAX, comm),
                          "cannot total data moved");
                if (tmpMin != tmpMax) {
                        if (rank == 0) {
                                WARN("inconsistent file size by different tasks");
                        }
                        /* incorrect, but now consistent across tasks */
                        fsize = tmpMin;
                }
        }

        return (fsize);
}

static int
DFS_Statfs(const char *path, ior_aiori_statfs_t *sfs, IOR_param_t * param)
{
        return 0;
}

static int
DFS_Mkdir(const char *path, mode_t mode, IOR_param_t * param)
{
        dfs_obj_t *parent = NULL;
	mode_t pmode;
	char *name = NULL, *dir_name = NULL;
	int rc;

	rc = parse_filename(path, &name, &dir_name);
        DERR(rc, "Failed to parse path %s", path);

	assert(dir_name);
        assert(name);

	rc = dfs_lookup(dfs, dir_name, O_RDWR, &parent, &pmode);
        DERR(rc, "dfs_lookup() of %s Failed", dir_name);

	rc = dfs_mkdir(dfs, parent, name, mode);
        DERR(rc, "dfs_mkdir() of %s Failed", name);

out:
	if (name)
		free(name);
	if (dir_name)
		free(dir_name);
	if (parent)
		dfs_release(parent);
        if (rc)
                return -1;
	return rc;
}

static int
DFS_Rmdir(const char *path, IOR_param_t * param)
{
        dfs_obj_t *parent = NULL;
	mode_t pmode;
	char *name = NULL, *dir_name = NULL;
	int rc;

	rc = parse_filename(path, &name, &dir_name);
        DERR(rc, "Failed to parse path %s", path);

	assert(dir_name);
        assert(name);

	rc = dfs_lookup(dfs, dir_name, O_RDWR, &parent, &pmode);
        DERR(rc, "dfs_lookup() of %s Failed", dir_name);

	rc = dfs_remove(dfs, parent, name, false);
        DERR(rc, "dfs_remove() of %s Failed", name);

out:
	if (name)
		free(name);
	if (dir_name)
		free(dir_name);
	if (parent)
		dfs_release(parent);
        if (rc)
                return -1;
	return rc;
}

static int
DFS_Access(const char *path, int mode, IOR_param_t * param)
{
        dfs_obj_t *parent = NULL;
	mode_t pmode;
	char *name = NULL, *dir_name = NULL;
        struct stat stbuf;
	int rc;

	rc = parse_filename(path, &name, &dir_name);
        DERR(rc, "Failed to parse path %s", path);

	assert(dir_name);

	rc = dfs_lookup(dfs, dir_name, O_RDWR, &parent, &pmode);
        DERR(rc, "dfs_lookup() of %s Failed", dir_name);

        if (name && strcmp(name, ".") == 0) {
                free(name);
                name = NULL;
        }
	rc = dfs_stat(dfs, parent, name, &stbuf);

out:
	if (name)
		free(name);
	if (dir_name)
		free(dir_name);
	if (parent)
		dfs_release(parent);
        if (rc)
                return -1;
	return rc;
}

static int
DFS_Stat(const char *path, struct stat *buf, IOR_param_t * param)
{
        dfs_obj_t *parent = NULL;
	mode_t pmode;
	char *name = NULL, *dir_name = NULL;
	int rc;

	rc = parse_filename(path, &name, &dir_name);
        DERR(rc, "Failed to parse path %s", path);

	assert(dir_name);
        assert(name);

	rc = dfs_lookup(dfs, dir_name, O_RDONLY, &parent, &pmode);
        DERR(rc, "dfs_lookup() of %s Failed", dir_name);

	rc = dfs_stat(dfs, parent, name, buf);
        DERR(rc, "dfs_stat() of %s Failed", name);

out:
	if (name)
		free(name);
	if (dir_name)
		free(dir_name);
	if (parent)
		dfs_release(parent);
        if (rc)
                return -1;
	return rc;
}