/*
   Copyright (c) 2007-2012 Red Hat, Inc. <http://www.redhat.com>
   This file is part of GlusterFS.

   This file is licensed to you under your choice of the GNU Lesser
   General Public License, version 3 or any later version (LGPLv3 or
   later), or the GNU General Public License, version 2 (GPLv2), in all
   cases as published by the Free Software Foundation.
*/

#include <glusterfs/glusterfs.h>
#include <glusterfs/dict.h>
#include <glusterfs/xlator.h>
#include <glusterfs/logging.h>
#include <glusterfs/run.h>
#include <glusterfs/defaults.h>
#include <glusterfs/syscall.h>
#include <glusterfs/compat.h>
#include <glusterfs/compat-errno.h>
#include "glusterd.h"
#include "glusterd-sm.h"
#include "glusterd-op-sm.h"
#include "glusterd-utils.h"
#include "glusterd-store.h"
#include "glusterd-hooks.h"
#include "glusterd-messages.h"

#include <fnmatch.h>

#define EMPTY ""
char glusterd_hook_dirnames[GD_OP_MAX][256] = {
    [GD_OP_NONE] = EMPTY,
    [GD_OP_CREATE_VOLUME] = "create",
    [GD_OP_START_BRICK] = EMPTY,
    [GD_OP_STOP_BRICK] = EMPTY,
    [GD_OP_DELETE_VOLUME] = "delete",
    [GD_OP_START_VOLUME] = "start",
    [GD_OP_STOP_VOLUME] = "stop",
    [GD_OP_DEFRAG_VOLUME] = EMPTY,
    [GD_OP_ADD_BRICK] = "add-brick",
    [GD_OP_REMOVE_BRICK] = "remove-brick",
    [GD_OP_REPLACE_BRICK] = EMPTY,
    [GD_OP_SET_VOLUME] = "set",
    [GD_OP_RESET_VOLUME] = "reset",
    [GD_OP_SYNC_VOLUME] = EMPTY,
    [GD_OP_LOG_ROTATE] = EMPTY,
    [GD_OP_GSYNC_CREATE] = "gsync-create",
    [GD_OP_GSYNC_SET] = EMPTY,
    [GD_OP_PROFILE_VOLUME] = EMPTY,
    [GD_OP_QUOTA] = EMPTY,
    [GD_OP_STATUS_VOLUME] = EMPTY,
    [GD_OP_REBALANCE] = EMPTY,
    [GD_OP_HEAL_VOLUME] = EMPTY,
    [GD_OP_STATEDUMP_VOLUME] = EMPTY,
    [GD_OP_LIST_VOLUME] = EMPTY,
    [GD_OP_CLEARLOCKS_VOLUME] = EMPTY,
    [GD_OP_DEFRAG_BRICK_VOLUME] = EMPTY,
    [GD_OP_RESET_BRICK] = EMPTY,
};
#undef EMPTY

static gf_boolean_t
glusterd_is_hook_enabled(char *script)
{
    return (script[0] == 'S' && (fnmatch("*.rpmsave", script, 0) != 0) &&
            (fnmatch("*.rpmnew", script, 0) != 0));
}

int
glusterd_hooks_create_hooks_directory(char *basedir)
{
    int ret = -1;
    int op = GD_OP_NONE;
    int type = GD_COMMIT_HOOK_NONE;
    char version_dir[PATH_MAX] = {
        0,
    };
    char path[PATH_MAX] = {
        0,
    };
    char *cmd_subdir = NULL;
    char type_subdir[GD_COMMIT_HOOK_MAX][256] = {{
                                                     0,
                                                 },
                                                 "pre",
                                                 "post"};
    glusterd_conf_t *priv = NULL;
    int32_t len = 0;

    priv = THIS->private;

    snprintf(path, sizeof(path), "%s/hooks", basedir);
    ret = mkdir_p(path, 0755, _gf_true);
    if (ret) {
        gf_msg(THIS->name, GF_LOG_CRITICAL, errno, GD_MSG_CREATE_DIR_FAILED,
               "Unable to create %s", path);
        goto out;
    }

    GLUSTERD_GET_HOOKS_DIR(version_dir, GLUSTERD_HOOK_VER, priv);
    ret = mkdir_p(version_dir, 0755, _gf_true);
    if (ret) {
        gf_msg(THIS->name, GF_LOG_CRITICAL, errno, GD_MSG_CREATE_DIR_FAILED,
               "Unable to create %s", version_dir);
        goto out;
    }

    for (op = GD_OP_NONE + 1; op < GD_OP_MAX; op++) {
        cmd_subdir = glusterd_hooks_get_hooks_cmd_subdir(op);
        if (strlen(cmd_subdir) == 0)
            continue;

        len = snprintf(path, sizeof(path), "%s/%s", version_dir, cmd_subdir);
        if ((len < 0) || (len >= sizeof(path))) {
            ret = -1;
            goto out;
        }
        ret = mkdir_p(path, 0755, _gf_true);
        if (ret) {
            gf_msg(THIS->name, GF_LOG_CRITICAL, errno, GD_MSG_CREATE_DIR_FAILED,
                   "Unable to create %s", path);
            goto out;
        }

        for (type = GD_COMMIT_HOOK_PRE; type < GD_COMMIT_HOOK_MAX; type++) {
            len = snprintf(path, sizeof(path), "%s/%s/%s", version_dir,
                           cmd_subdir, type_subdir[type]);
            if ((len < 0) || (len >= sizeof(path))) {
                ret = -1;
                goto out;
            }
            ret = mkdir_p(path, 0755, _gf_true);
            if (ret) {
                gf_msg(THIS->name, GF_LOG_CRITICAL, errno,
                       GD_MSG_CREATE_DIR_FAILED, "Unable to create %s", path);
                goto out;
            }
        }
    }

    ret = 0;
out:
    return ret;
}

char *
glusterd_hooks_get_hooks_cmd_subdir(glusterd_op_t op)
{
    GF_ASSERT((op > GD_OP_NONE) && (op < GD_OP_MAX));

    return glusterd_hook_dirnames[op];
}

void
glusterd_hooks_add_working_dir(runner_t *runner, glusterd_conf_t *priv)
{
    runner_argprintf(runner, "--gd-workdir=%s", priv->workdir);
}

void
glusterd_hooks_add_op(runner_t *runner, char *op)
{
    runner_argprintf(runner, "--volume-op=%s", op);
}

void
glusterd_hooks_add_hooks_version(runner_t *runner)
{
    runner_argprintf(runner, "--version=%d", GLUSTERD_HOOK_VER);
}

static void
glusterd_hooks_add_custom_args(dict_t *dict, runner_t *runner)
{
    char *hooks_args = NULL;
    int32_t ret = -1;
    xlator_t *this = NULL;

    this = THIS;
    GF_VALIDATE_OR_GOTO("glusterd", this, out);
    GF_VALIDATE_OR_GOTO(this->name, dict, out);
    GF_VALIDATE_OR_GOTO(this->name, runner, out);

    ret = dict_get_str(dict, "hooks_args", &hooks_args);
    if (ret)
        gf_msg_debug(this->name, 0, "No Hooks Arguments.");
    else
        gf_msg_debug(this->name, 0, "Hooks Args = %s", hooks_args);

    if (hooks_args)
        runner_argprintf(runner, "%s", hooks_args);

out:
    return;
}

int
glusterd_hooks_set_volume_args(dict_t *dict, runner_t *runner)
{
    int i = 0;
    int count = 0;
    int ret = -1;
    char query[1024] = {
        0,
    };
    char *key = NULL;
    char *value = NULL;

    ret = dict_get_int32(dict, "count", &count);
    if (ret)
        goto out;

    /* This will not happen unless op_ctx
     * is corrupted*/
    if (!count)
        goto out;

    runner_add_arg(runner, "-o");
    for (i = 1; ret == 0; i++) {
        snprintf(query, sizeof(query), "key%d", i);
        ret = dict_get_str(dict, query, &key);
        if (ret)
            continue;

        snprintf(query, sizeof(query), "value%d", i);
        ret = dict_get_str(dict, query, &value);
        if (ret)
            continue;

        runner_argprintf(runner, "%s=%s", key, value);
    }

    glusterd_hooks_add_custom_args(dict, runner);

    ret = 0;
out:
    return ret;
}

static int
glusterd_hooks_add_op_args(runner_t *runner, glusterd_op_t op, dict_t *op_ctx,
                           glusterd_commit_hook_type_t type)
{
    int vol_count = 0;
    gf_boolean_t truth = _gf_false;
    glusterd_volinfo_t *voliter = NULL;
    glusterd_conf_t *priv = NULL;
    int ret = -1;

    priv = THIS->private;
    cds_list_for_each_entry(voliter, &priv->volumes, vol_list)
    {
        if (glusterd_is_volume_started(voliter))
            vol_count++;
    }

    ret = 0;
    switch (op) {
        case GD_OP_START_VOLUME:
            if (type == GD_COMMIT_HOOK_PRE && vol_count == 0)
                truth = _gf_true;

            else if (type == GD_COMMIT_HOOK_POST && vol_count == 1)
                truth = _gf_true;

            else
                truth = _gf_false;

            runner_argprintf(runner, "--first=%s", truth ? "yes" : "no");

            glusterd_hooks_add_hooks_version(runner);
            glusterd_hooks_add_op(runner, "start");
            glusterd_hooks_add_working_dir(runner, priv);

            break;

        case GD_OP_STOP_VOLUME:
            if (type == GD_COMMIT_HOOK_PRE && vol_count == 1)
                truth = _gf_true;

            else if (type == GD_COMMIT_HOOK_POST && vol_count == 0)
                truth = _gf_true;

            else
                truth = _gf_false;

            runner_argprintf(runner, "--last=%s", truth ? "yes" : "no");
            break;

        case GD_OP_SET_VOLUME:
            ret = glusterd_hooks_set_volume_args(op_ctx, runner);
            glusterd_hooks_add_working_dir(runner, priv);
            break;

        case GD_OP_GSYNC_CREATE:
            glusterd_hooks_add_custom_args(op_ctx, runner);
            break;

        case GD_OP_ADD_BRICK:
            glusterd_hooks_add_hooks_version(runner);
            glusterd_hooks_add_op(runner, "add-brick");
            glusterd_hooks_add_working_dir(runner, priv);
            break;

        case GD_OP_RESET_VOLUME:
            glusterd_hooks_add_hooks_version(runner);
            glusterd_hooks_add_op(runner, "reset");
            glusterd_hooks_add_working_dir(runner, priv);
            break;

        default:
            break;
    }

    return ret;
}

int
glusterd_hooks_run_hooks(char *hooks_path, glusterd_op_t op, dict_t *op_ctx,
                         glusterd_commit_hook_type_t type)
{
    xlator_t *this = NULL;
    runner_t runner = {
        0,
    };
    DIR *hookdir = NULL;
    struct dirent *entry = NULL;
    struct dirent scratch[2] = {
        {
            0,
        },
    };
    char *volname = NULL;
    char **lines = NULL;
    int N = 8; /*arbitrary*/
    int lineno = 0;
    int line_count = 0;
    int ret = -1;

    this = THIS;

    ret = dict_get_str(op_ctx, "volname", &volname);
    if (ret) {
        gf_msg(this->name, GF_LOG_CRITICAL, errno, GD_MSG_DICT_GET_FAILED,
               "Failed to get volname "
               "from operation context");
        goto out;
    }

    hookdir = sys_opendir(hooks_path);
    if (!hookdir) {
        ret = -1;
        gf_msg(this->name, GF_LOG_ERROR, errno, GD_MSG_DIR_OP_FAILED,
               "Failed to open dir %s", hooks_path);
        goto out;
    }

    lines = GF_CALLOC(1, N * sizeof(*lines), gf_gld_mt_charptr);
    if (!lines) {
        ret = -1;
        goto out;
    }

    ret = -1;
    line_count = 0;
    GF_SKIP_IRRELEVANT_ENTRIES(entry, hookdir, scratch);
    while (entry) {
        if (line_count == N - 1) {
            N *= 2;
            lines = GF_REALLOC(lines, N * sizeof(char *));
            if (!lines)
                goto out;
        }

        if (glusterd_is_hook_enabled(entry->d_name)) {
            lines[line_count] = gf_strdup(entry->d_name);
            line_count++;
        }

        GF_SKIP_IRRELEVANT_ENTRIES(entry, hookdir, scratch);
    }

    lines[line_count] = NULL;
    lines = GF_REALLOC(lines, (line_count + 1) * sizeof(char *));
    if (!lines)
        goto out;

    qsort(lines, line_count, sizeof(*lines), glusterd_compare_lines);

    for (lineno = 0; lineno < line_count; lineno++) {
        runinit(&runner);
        runner_argprintf(&runner, "%s/%s", hooks_path, lines[lineno]);
        /*Add future command line arguments to hook scripts below*/
        runner_argprintf(&runner, "--volname=%s", volname);
        ret = glusterd_hooks_add_op_args(&runner, op, op_ctx, type);
        if (ret) {
            gf_msg(this->name, GF_LOG_ERROR, 0, GD_MSG_ADD_OP_ARGS_FAIL,
                   "Failed to add "
                   "command specific arguments");
            goto out;
        }

        ret = runner_run_reuse(&runner);
        if (ret) {
            runner_log(&runner, this->name, GF_LOG_ERROR,
                       "Failed to execute script");
        } else {
            runner_log(&runner, this->name, GF_LOG_INFO, "Ran script");
        }
        runner_end(&runner);
    }

    ret = 0;
out:
    if (lines) {
        for (lineno = 0; lineno < line_count + 1; lineno++)
            GF_FREE(lines[lineno]);

        GF_FREE(lines);
    }

    if (hookdir)
        sys_closedir(hookdir);

    return ret;
}

int
glusterd_hooks_post_stub_enqueue(char *scriptdir, glusterd_op_t op,
                                 dict_t *op_ctx)
{
    int ret = -1;
    glusterd_hooks_stub_t *stub = NULL;
    glusterd_hooks_private_t *hooks_priv = NULL;
    glusterd_conf_t *conf = NULL;

    conf = THIS->private;
    hooks_priv = conf->hooks_priv;

    ret = glusterd_hooks_stub_init(&stub, scriptdir, op, op_ctx);
    if (ret)
        goto out;

    pthread_mutex_lock(&hooks_priv->mutex);
    {
        hooks_priv->waitcount++;
        cds_list_add_tail(&stub->all_hooks, &hooks_priv->list);
        pthread_cond_signal(&hooks_priv->cond);
    }
    pthread_mutex_unlock(&hooks_priv->mutex);

    ret = 0;
out:
    return ret;
}

int
glusterd_hooks_stub_init(glusterd_hooks_stub_t **stub, char *scriptdir,
                         glusterd_op_t op, dict_t *op_ctx)
{
    int ret = -1;
    glusterd_hooks_stub_t *hooks_stub = NULL;

    GF_ASSERT(stub);
    if (!stub)
        goto out;

    hooks_stub = GF_CALLOC(1, sizeof(*hooks_stub), gf_gld_mt_hooks_stub_t);
    if (!hooks_stub)
        goto out;

    CDS_INIT_LIST_HEAD(&hooks_stub->all_hooks);
    hooks_stub->op = op;
    hooks_stub->scriptdir = gf_strdup(scriptdir);
    if (!hooks_stub->scriptdir)
        goto out;

    hooks_stub->op_ctx = dict_copy_with_ref(op_ctx, hooks_stub->op_ctx);
    if (!hooks_stub->op_ctx)
        goto out;

    *stub = hooks_stub;
    ret = 0;
out:
    if (ret) {
        gf_msg(THIS->name, GF_LOG_ERROR, 0, GD_MSG_POST_HOOK_STUB_INIT_FAIL,
               "Failed to initialize "
               "post hooks stub");
        glusterd_hooks_stub_cleanup(hooks_stub);
    }

    return ret;
}

void
glusterd_hooks_stub_cleanup(glusterd_hooks_stub_t *stub)
{
    if (!stub) {
        gf_msg_callingfn(THIS->name, GF_LOG_WARNING, 0, GD_MSG_HOOK_STUB_NULL,
                         "hooks_stub is NULL");
        return;
    }

    if (stub->op_ctx)
        dict_unref(stub->op_ctx);

    GF_FREE(stub->scriptdir);

    GF_FREE(stub);
}

static void *
hooks_worker(void *args)
{
    glusterd_conf_t *conf = NULL;
    glusterd_hooks_private_t *hooks_priv = NULL;
    glusterd_hooks_stub_t *stub = NULL;

    THIS = args;
    conf = THIS->private;
    hooks_priv = conf->hooks_priv;

    for (;;) {
        pthread_mutex_lock(&hooks_priv->mutex);
        {
            while (cds_list_empty(&hooks_priv->list)) {
                pthread_cond_wait(&hooks_priv->cond, &hooks_priv->mutex);
            }
            stub = cds_list_entry(hooks_priv->list.next, glusterd_hooks_stub_t,
                                  all_hooks);
            cds_list_del_init(&stub->all_hooks);
            hooks_priv->waitcount--;
        }
        pthread_mutex_unlock(&hooks_priv->mutex);

        glusterd_hooks_run_hooks(stub->scriptdir, stub->op, stub->op_ctx,
                                 GD_COMMIT_HOOK_POST);
        glusterd_hooks_stub_cleanup(stub);
    }

    return NULL;
}

int
glusterd_hooks_priv_init(glusterd_hooks_private_t **new)
{
    int ret = -1;
    glusterd_hooks_private_t *hooks_priv = NULL;

    if (!new)
        goto out;

    hooks_priv = GF_CALLOC(1, sizeof(*hooks_priv), gf_gld_mt_hooks_priv_t);
    if (!hooks_priv)
        goto out;

    pthread_mutex_init(&hooks_priv->mutex, NULL);
    pthread_cond_init(&hooks_priv->cond, NULL);
    CDS_INIT_LIST_HEAD(&hooks_priv->list);
    hooks_priv->waitcount = 0;

    *new = hooks_priv;
    ret = 0;
out:
    return ret;
}

int
glusterd_hooks_spawn_worker(xlator_t *this)
{
    int ret = -1;
    glusterd_conf_t *conf = NULL;
    glusterd_hooks_private_t *hooks_priv = NULL;

    ret = glusterd_hooks_priv_init(&hooks_priv);
    if (ret)
        goto out;

    conf = this->private;
    conf->hooks_priv = hooks_priv;
    ret = gf_thread_create(&hooks_priv->worker, NULL, hooks_worker,
                           (void *)this, "gdhooks");
    if (ret)
        gf_msg(this->name, GF_LOG_CRITICAL, errno, GD_MSG_SPAWN_THREADS_FAIL,
               "Failed to spawn post "
               "hooks worker thread");
out:
    return ret;
}