"""
Module to provide redis functionality to Salt

.. versionadded:: 2014.7.0

:configuration: This module requires the redis python module and uses the
    following defaults which may be overridden in the minion configuration:

.. code-block:: yaml

    redis.host: 'salt'
    redis.port: 6379
    redis.db: 0
    redis.password: None
"""

import salt.utils.args

try:
    import redis

    HAS_REDIS = True
except ImportError:
    HAS_REDIS = False

__virtualname__ = "redis"


def __virtual__():
    """
    Only load this module if redis python module is installed
    """
    if HAS_REDIS:
        return __virtualname__
    else:
        return (
            False,
            "The redis execution module failed to load: the redis python library is not"
            " available.",
        )


def _connect(host=None, port=None, db=None, password=None):
    """
    Returns an instance of the redis client
    """
    if not host:
        host = __salt__["config.option"]("redis.host")
    if not port:
        port = __salt__["config.option"]("redis.port")
    if db is None:
        # Use ``is None`` rather than ``not db`` because ``0`` is the default
        # Redis database index and a perfectly valid explicit value: the
        # truthy check would silently replace it with the config value.
        db = __salt__["config.option"]("redis.db")
    if not password:
        password = __salt__["config.option"]("redis.password")

    return redis.StrictRedis(host, port, db, password, decode_responses=True)


def _sconnect(host=None, port=None, password=None):
    """
    Returns an instance of the redis client
    """
    if host is None:
        host = __salt__["config.option"]("redis_sentinel.host", "localhost")
    if port is None:
        port = __salt__["config.option"]("redis_sentinel.port", 26379)
    if password is None:
        password = __salt__["config.option"]("redis_sentinel.password")

    return redis.StrictRedis(host, port, password=password, decode_responses=True)


def bgrewriteaof(host=None, port=None, db=None, password=None):
    """
    Asynchronously rewrite the append-only file

    CLI Example:

    .. code-block:: bash

        salt '*' redis.bgrewriteaof
    """
    server = _connect(host, port, db, password)
    return server.bgrewriteaof()


def bgsave(host=None, port=None, db=None, password=None):
    """
    Asynchronously save the dataset to disk

    CLI Example:

    .. code-block:: bash

        salt '*' redis.bgsave
    """
    server = _connect(host, port, db, password)
    return server.bgsave()


def config_get(pattern="*", host=None, port=None, db=None, password=None):
    """
    Get redis server configuration values

    CLI Example:

    .. code-block:: bash

        salt '*' redis.config_get
        salt '*' redis.config_get port
    """
    server = _connect(host, port, db, password)
    return server.config_get(pattern)


def config_set(name, value, host=None, port=None, db=None, password=None):
    """
    Set redis server configuration values

    CLI Example:

    .. code-block:: bash

        salt '*' redis.config_set masterauth luv_kittens
    """
    server = _connect(host, port, db, password)
    return server.config_set(name, value)


def dbsize(host=None, port=None, db=None, password=None):
    """
    Return the number of keys in the selected database

    CLI Example:

    .. code-block:: bash

        salt '*' redis.dbsize
    """
    server = _connect(host, port, db, password)
    return server.dbsize()


def delete(*keys, **connection_args):
    """
    Deletes the keys from redis, returns number of keys deleted

    CLI Example:

    .. code-block:: bash

        salt '*' redis.delete foo
    """
    # Get connection args from keywords if set
    conn_args = {}
    for arg in ["host", "port", "db", "password"]:
        if arg in connection_args:
            conn_args[arg] = connection_args[arg]

    server = _connect(**conn_args)
    return server.delete(*keys)


def exists(key, host=None, port=None, db=None, password=None):
    """
    Return true if the key exists in redis

    CLI Example:

    .. code-block:: bash

        salt '*' redis.exists foo
    """
    server = _connect(host, port, db, password)
    return server.exists(key)


def expire(key, seconds, host=None, port=None, db=None, password=None):
    """
    Set a keys time to live in seconds

    CLI Example:

    .. code-block:: bash

        salt '*' redis.expire foo 300
    """
    server = _connect(host, port, db, password)
    return server.expire(key, seconds)


def expireat(key, timestamp, host=None, port=None, db=None, password=None):
    """
    Set a keys expire at given UNIX time

    CLI Example:

    .. code-block:: bash

        salt '*' redis.expireat foo 1400000000
    """
    server = _connect(host, port, db, password)
    return server.expireat(key, timestamp)


def flushall(host=None, port=None, db=None, password=None):
    """
    Remove all keys from all databases

    CLI Example:

    .. code-block:: bash

        salt '*' redis.flushall
    """
    server = _connect(host, port, db, password)
    return server.flushall()


def flushdb(host=None, port=None, db=None, password=None):
    """
    Remove all keys from the selected database

    CLI Example:

    .. code-block:: bash

        salt '*' redis.flushdb
    """
    server = _connect(host, port, db, password)
    return server.flushdb()


def get_key(key, host=None, port=None, db=None, password=None):
    """
    Get redis key value

    CLI Example:

    .. code-block:: bash

        salt '*' redis.get_key foo
    """
    server = _connect(host, port, db, password)
    return server.get(key)


def hdel(key, *fields, **options):
    """
    Delete one of more hash fields.

    .. versionadded:: 2017.7.0

    CLI Example:

    .. code-block:: bash

        salt '*' redis.hdel foo_hash bar_field1 bar_field2
    """
    host = options.get("host", None)
    port = options.get("port", None)
    database = options.get("db", None)
    password = options.get("password", None)
    server = _connect(host, port, database, password)
    return server.hdel(key, *fields)


def hexists(key, field, host=None, port=None, db=None, password=None):
    """
    Determine if a hash fields exists.

    .. versionadded:: 2017.7.0

    CLI Example:

    .. code-block:: bash

        salt '*' redis.hexists foo_hash bar_field
    """
    server = _connect(host, port, db, password)
    return server.hexists(key, field)


def hget(key, field, host=None, port=None, db=None, password=None):
    """
    Get specific field value from a redis hash, returns dict

    CLI Example:

    .. code-block:: bash

        salt '*' redis.hget foo_hash bar_field
    """
    server = _connect(host, port, db, password)
    return server.hget(key, field)


def hgetall(key, host=None, port=None, db=None, password=None):
    """
    Get all fields and values from a redis hash, returns dict

    CLI Example:

    .. code-block:: bash

        salt '*' redis.hgetall foo_hash
    """
    server = _connect(host, port, db, password)
    return server.hgetall(key)


def hincrby(key, field, increment=1, host=None, port=None, db=None, password=None):
    """
    Increment the integer value of a hash field by the given number.

    .. versionadded:: 2017.7.0

    CLI Example:

    .. code-block:: bash

        salt '*' redis.hincrby foo_hash bar_field 5
    """
    server = _connect(host, port, db, password)
    return server.hincrby(key, field, amount=increment)


def hincrbyfloat(
    key, field, increment=1.0, host=None, port=None, db=None, password=None
):
    """
    Increment the float value of a hash field by the given number.

    .. versionadded:: 2017.7.0

    CLI Example:

    .. code-block:: bash

        salt '*' redis.hincrbyfloat foo_hash bar_field 5.17
    """
    server = _connect(host, port, db, password)
    return server.hincrbyfloat(key, field, amount=increment)


def hlen(key, host=None, port=None, db=None, password=None):
    """
    Returns number of fields of a hash.

    .. versionadded:: 2017.7.0

    CLI Example:

    .. code-block:: bash

        salt '*' redis.hlen foo_hash
    """
    server = _connect(host, port, db, password)
    return server.hlen(key)


def hmget(key, *fields, **options):
    """
    Returns the values of all the given hash fields.

    .. versionadded:: 2017.7.0

    CLI Example:

    .. code-block:: bash

        salt '*' redis.hmget foo_hash bar_field1 bar_field2
    """
    host = options.get("host", None)
    port = options.get("port", None)
    database = options.get("db", None)
    password = options.get("password", None)
    server = _connect(host, port, database, password)
    return server.hmget(key, *fields)


def hmset(key, **fieldsvals):
    """
    Sets multiple hash fields to multiple values.

    .. versionadded:: 2017.7.0

    CLI Example:

    .. code-block:: bash

        salt '*' redis.hmset foo_hash bar_field1=bar_value1 bar_field2=bar_value2
    """
    host = fieldsvals.pop("host", None)
    port = fieldsvals.pop("port", None)
    database = fieldsvals.pop("db", None)
    password = fieldsvals.pop("password", None)
    server = _connect(host, port, database, password)
    return server.hmset(key, salt.utils.args.clean_kwargs(**fieldsvals))


def hset(key, field, value, host=None, port=None, db=None, password=None):
    """
    Set the value of a hash field.

    .. versionadded:: 2017.7.0

    CLI Example:

    .. code-block:: bash

        salt '*' redis.hset foo_hash bar_field bar_value
    """
    server = _connect(host, port, db, password)
    return server.hset(key, field, value)


def hsetnx(key, field, value, host=None, port=None, db=None, password=None):
    """
    Set the value of a hash field only if the field does not exist.

    .. versionadded:: 2017.7.0

    CLI Example:

    .. code-block:: bash

        salt '*' redis.hsetnx foo_hash bar_field bar_value
    """
    server = _connect(host, port, db, password)
    return server.hsetnx(key, field, value)


def hvals(key, host=None, port=None, db=None, password=None):
    """
    Return all the values in a hash.

    .. versionadded:: 2017.7.0

    CLI Example:

    .. code-block:: bash

        salt '*' redis.hvals foo_hash bar_field1 bar_value1
    """
    server = _connect(host, port, db, password)
    return server.hvals(key)


def hscan(
    key, cursor=0, match=None, count=None, host=None, port=None, db=None, password=None
):
    """
    Incrementally iterate hash fields and associated values.

    .. versionadded:: 2017.7.0

    CLI Example:

    .. code-block:: bash

        salt '*' redis.hscan foo_hash match='field_prefix_*' count=1
    """
    server = _connect(host, port, db, password)
    return server.hscan(key, cursor=cursor, match=match, count=count)


def info(host=None, port=None, db=None, password=None):
    """
    Get information and statistics about the server

    CLI Example:

    .. code-block:: bash

        salt '*' redis.info
    """
    server = _connect(host, port, db, password)
    return server.info()


def keys(pattern="*", host=None, port=None, db=None, password=None):
    """
    Get redis keys, supports glob style patterns

    CLI Example:

    .. code-block:: bash

        salt '*' redis.keys
        salt '*' redis.keys test*
    """
    server = _connect(host, port, db, password)
    return server.keys(pattern)


def key_type(key, host=None, port=None, db=None, password=None):
    """
    Get redis key type

    CLI Example:

    .. code-block:: bash

        salt '*' redis.type foo
    """
    server = _connect(host, port, db, password)
    return server.type(key)


def lastsave(host=None, port=None, db=None, password=None):
    """
    Get the UNIX time in seconds of the last successful save to disk

    CLI Example:

    .. code-block:: bash

        salt '*' redis.lastsave
    """
    # Use of %s to get the timestamp is not supported by Python. The reason it
    # works is because it's passed to the system strftime which may not support
    # it. See: https://stackoverflow.com/a/11743262
    server = _connect(host, port, db, password)
    return int(server.lastsave().timestamp())


def llen(key, host=None, port=None, db=None, password=None):
    """
    Get the length of a list in Redis

    CLI Example:

    .. code-block:: bash

        salt '*' redis.llen foo_list
    """
    server = _connect(host, port, db, password)
    return server.llen(key)


def lrange(key, start, stop, host=None, port=None, db=None, password=None):
    """
    Get a range of values from a list in Redis

    CLI Example:

    .. code-block:: bash

        salt '*' redis.lrange foo_list 0 10
    """
    server = _connect(host, port, db, password)
    return server.lrange(key, start, stop)


def ping(host=None, port=None, db=None, password=None):
    """
    Ping the server, returns False on connection errors

    CLI Example:

    .. code-block:: bash

        salt '*' redis.ping
    """
    server = _connect(host, port, db, password)
    try:
        return server.ping()
    except redis.ConnectionError:
        return False


def save(host=None, port=None, db=None, password=None):
    """
    Synchronously save the dataset to disk

    CLI Example:

    .. code-block:: bash

        salt '*' redis.save
    """
    server = _connect(host, port, db, password)
    return server.save()


def set_key(key, value, host=None, port=None, db=None, password=None):
    """
    Set redis key value

    CLI Example:

    .. code-block:: bash

        salt '*' redis.set_key foo bar
    """
    server = _connect(host, port, db, password)
    return server.set(key, value)


def shutdown(host=None, port=None, db=None, password=None):
    """
    Synchronously save the dataset to disk and then shut down the server

    CLI Example:

    .. code-block:: bash

        salt '*' redis.shutdown
    """
    server = _connect(host, port, db, password)
    try:
        # Return false if unable to ping server
        server.ping()
    except redis.ConnectionError:
        return False

    server.shutdown()
    try:
        # This should fail now if the server is shutdown, which we want
        server.ping()
    except redis.ConnectionError:
        return True
    return False


def slaveof(
    master_host=None, master_port=None, host=None, port=None, db=None, password=None
):
    """
    Make the server a slave of another instance, or promote it as master

    CLI Example:

    .. code-block:: bash

        # Become slave of redis-n01.example.com:6379
        salt '*' redis.slaveof redis-n01.example.com 6379
        salt '*' redis.slaveof redis-n01.example.com
        # Become master
        salt '*' redis.slaveof
    """
    if master_host and not master_port:
        master_port = 6379
    server = _connect(host, port, db, password)
    return server.slaveof(master_host, master_port)


def smembers(key, host=None, port=None, db=None, password=None):
    """
    Get members in a Redis set

    CLI Example:

    .. code-block:: bash

        salt '*' redis.smembers foo_set
    """
    server = _connect(host, port, db, password)
    return list(server.smembers(key))


def time(host=None, port=None, db=None, password=None):
    """
    Return the current server UNIX time in seconds

    CLI Example:

    .. code-block:: bash

        salt '*' redis.time
    """
    server = _connect(host, port, db, password)
    return server.time()[0]


def zcard(key, host=None, port=None, db=None, password=None):
    """
    Get the length of a sorted set in Redis

    CLI Example:

    .. code-block:: bash

        salt '*' redis.zcard foo_sorted
    """
    server = _connect(host, port, db, password)
    return server.zcard(key)


def zrange(key, start, stop, host=None, port=None, db=None, password=None):
    """
    Get a range of values from a sorted set in Redis by index

    CLI Example:

    .. code-block:: bash

        salt '*' redis.zrange foo_sorted 0 10
    """
    server = _connect(host, port, db, password)
    return server.zrange(key, start, stop)


def sentinel_get_master_ip(master, host=None, port=None, password=None):
    """
    Get ip for sentinel master

    .. versionadded:: 2016.3.0

    CLI Example:

    .. code-block:: bash

        salt '*' redis.sentinel_get_master_ip 'mymaster'
    """
    server = _sconnect(host, port, password)
    ret = server.sentinel_get_master_addr_by_name(master)
    return dict(list(zip(("master_host", "master_port"), ret)))


def get_master_ip(host=None, port=None, password=None):
    """
    Get host information about slave

    .. versionadded:: 2016.3.0

    CLI Example:

    .. code-block:: bash

        salt '*' redis.get_master_ip
    """
    server = _connect(host=host, port=port, password=password)
    srv_info = server.info()
    ret = (srv_info.get("master_host", ""), srv_info.get("master_port", ""))
    return dict(list(zip(("master_host", "master_port"), ret)))
