"""
OpenTelemetry semantic convention attributes for Redis.

This module provides constants and helper functions for building OTel attributes
according to the semantic conventions for database clients.

Reference: https://opentelemetry.io/docs/specs/semconv/database/redis/
"""

from enum import Enum
from typing import TYPE_CHECKING, Any, Dict, Optional, Union

import redis

if TYPE_CHECKING:
    from redis.asyncio.multidb.database import AsyncDatabase
    from redis.connection import ConnectionPoolInterface
    from redis.multidb.database import SyncDatabase

# Database semantic convention attributes
DB_SYSTEM = "db.system"
DB_NAMESPACE = "db.namespace"
DB_OPERATION_NAME = "db.operation.name"
DB_RESPONSE_STATUS_CODE = "db.response.status_code"
DB_STORED_PROCEDURE_NAME = "db.stored_procedure.name"

# Error attributes
ERROR_TYPE = "error.type"

# Network attributes
NETWORK_PEER_ADDRESS = "network.peer.address"
NETWORK_PEER_PORT = "network.peer.port"

# Server attributes
SERVER_ADDRESS = "server.address"
SERVER_PORT = "server.port"

# Connection pool attributes
DB_CLIENT_CONNECTION_POOL_NAME = "db.client.connection.pool.name"
DB_CLIENT_CONNECTION_STATE = "db.client.connection.state"
DB_CLIENT_CONNECTION_NAME = "db.client.connection.name"

# Geofailover attributes
DB_CLIENT_GEOFAILOVER_FAIL_FROM = "db.client.geofailover.fail_from"
DB_CLIENT_GEOFAILOVER_FAIL_TO = "db.client.geofailover.fail_to"
DB_CLIENT_GEOFAILOVER_REASON = "db.client.geofailover.reason"

# Redis-specific attributes
REDIS_CLIENT_LIBRARY = "redis.client.library"
REDIS_CLIENT_CONNECTION_PUBSUB = "redis.client.connection.pubsub"
REDIS_CLIENT_CONNECTION_CLOSE_REASON = "redis.client.connection.close.reason"
REDIS_CLIENT_CONNECTION_NOTIFICATION = "redis.client.connection.notification"
REDIS_CLIENT_OPERATION_RETRY_ATTEMPTS = "redis.client.operation.retry_attempts"
REDIS_CLIENT_OPERATION_BLOCKING = "redis.client.operation.blocking"
REDIS_CLIENT_PUBSUB_MESSAGE_DIRECTION = "redis.client.pubsub.message.direction"
REDIS_CLIENT_PUBSUB_CHANNEL = "redis.client.pubsub.channel"
REDIS_CLIENT_PUBSUB_SHARDED = "redis.client.pubsub.sharded"
REDIS_CLIENT_ERROR_INTERNAL = "redis.client.errors.internal"
REDIS_CLIENT_ERROR_CATEGORY = "redis.client.errors.category"
REDIS_CLIENT_STREAM_NAME = "redis.client.stream.name"
REDIS_CLIENT_CONSUMER_GROUP = "redis.client.consumer_group"
REDIS_CLIENT_CSC_RESULT = "redis.client.csc.result"
REDIS_CLIENT_CSC_REASON = "redis.client.csc.reason"


class ConnectionState(Enum):
    IDLE = "idle"
    USED = "used"


class PubSubDirection(Enum):
    PUBLISH = "publish"
    RECEIVE = "receive"


class CSCResult(Enum):
    HIT = "hit"
    MISS = "miss"


class CSCReason(Enum):
    FULL = "full"
    INVALIDATION = "invalidation"


class GeoFailoverReason(Enum):
    AUTOMATIC = "automatic"
    MANUAL = "manual"


class AttributeBuilder:
    """
    Helper class to build OTel semantic convention attributes for Redis operations.
    """

    @staticmethod
    def build_base_attributes(
        server_address: Optional[str] = None,
        server_port: Optional[int] = None,
        db_namespace: Optional[int] = None,
    ) -> Dict[str, Any]:
        """
        Build base attributes common to all Redis operations.

        Args:
            server_address: Redis server address (FQDN or IP)
            server_port: Redis server port
            db_namespace: Redis database index

        Returns:
            Dictionary of base attributes
        """
        attrs: Dict[str, Any] = {
            DB_SYSTEM: "redis",
            REDIS_CLIENT_LIBRARY: f"redis-py:v{redis.__version__}",
        }

        if server_address is not None:
            attrs[SERVER_ADDRESS] = server_address

        if server_port is not None:
            attrs[SERVER_PORT] = server_port

        if db_namespace is not None:
            attrs[DB_NAMESPACE] = str(db_namespace)

        return attrs

    @staticmethod
    def build_operation_attributes(
        command_name: Optional[str] = None,
        batch_size: Optional[int] = None,  # noqa
        network_peer_address: Optional[str] = None,
        network_peer_port: Optional[int] = None,
        stored_procedure_name: Optional[str] = None,
        retry_attempts: Optional[int] = None,
        is_blocking: Optional[bool] = None,
    ) -> Dict[str, Any]:
        """
        Build attributes for a Redis operation (command execution).

        Args:
            command_name: Redis command name (e.g., 'GET', 'SET', 'MULTI')
            batch_size: Number of commands in batch (for pipelines/transactions)
            network_peer_address: Resolved peer address
            network_peer_port: Peer port number
            stored_procedure_name: Lua script name or SHA1 digest
            retry_attempts: Number of retry attempts made
            is_blocking: Whether the operation is a blocking command

        Returns:
            Dictionary of operation attributes
        """
        attrs: Dict[str, Any] = {}

        if command_name is not None:
            attrs[DB_OPERATION_NAME] = command_name.upper()

        if network_peer_address is not None:
            attrs[NETWORK_PEER_ADDRESS] = network_peer_address

        if network_peer_port is not None:
            attrs[NETWORK_PEER_PORT] = network_peer_port

        if stored_procedure_name is not None:
            attrs[DB_STORED_PROCEDURE_NAME] = stored_procedure_name

        if retry_attempts is not None and retry_attempts > 0:
            attrs[REDIS_CLIENT_OPERATION_RETRY_ATTEMPTS] = retry_attempts

        if is_blocking is not None:
            attrs[REDIS_CLIENT_OPERATION_BLOCKING] = is_blocking

        return attrs

    @staticmethod
    def build_connection_attributes(
        pool_name: Optional[str] = None,
        connection_state: Optional[ConnectionState] = None,
        connection_name: Optional[str] = None,
        is_pubsub: Optional[bool] = None,
    ) -> Dict[str, Any]:
        """
        Build attributes for connection pool metrics.

        Args:
            pool_name: Unique connection pool name
            connection_state: Connection state ('idle' or 'used')
            is_pubsub: Whether this is a PubSub connection
            connection_name: Unique connection name

        Returns:
            Dictionary of connection pool attributes
        """
        attrs: Dict[str, Any] = AttributeBuilder.build_base_attributes()

        if pool_name is not None:
            attrs[DB_CLIENT_CONNECTION_POOL_NAME] = pool_name

        if connection_state is not None:
            attrs[DB_CLIENT_CONNECTION_STATE] = connection_state.value

        if is_pubsub is not None:
            attrs[REDIS_CLIENT_CONNECTION_PUBSUB] = is_pubsub

        if connection_name is not None:
            attrs[DB_CLIENT_CONNECTION_NAME] = connection_name

        return attrs

    @staticmethod
    def build_error_attributes(
        error_type: Optional[Exception] = None,
        is_internal: Optional[bool] = None,
    ) -> Dict[str, Any]:
        """
        Build error attributes.

        Args:
            is_internal: Whether the error is internal (e.g., timeout, network error)
            error_type: The exception that occurred

        Returns:
            Dictionary of error attributes
        """
        attrs: Dict[str, Any] = {}

        if error_type is not None:
            attrs[ERROR_TYPE] = error_type.__class__.__name__

            if (
                hasattr(error_type, "status_code")
                and error_type.status_code is not None
            ):
                attrs[DB_RESPONSE_STATUS_CODE] = error_type.status_code
            else:
                attrs[DB_RESPONSE_STATUS_CODE] = "error"

            if hasattr(error_type, "error_type") and error_type.error_type is not None:
                attrs[REDIS_CLIENT_ERROR_CATEGORY] = error_type.error_type.value
            else:
                attrs[REDIS_CLIENT_ERROR_CATEGORY] = "other"

        if is_internal is not None:
            attrs[REDIS_CLIENT_ERROR_INTERNAL] = is_internal

        return attrs

    @staticmethod
    def build_pubsub_message_attributes(
        direction: PubSubDirection,
        channel: Optional[str] = None,
        sharded: Optional[bool] = None,
    ) -> Dict[str, Any]:
        """
        Build attributes for a PubSub message.

        Args:
            direction: Message direction ('publish' or 'receive')
            channel: Pub/Sub channel name
            sharded: True if sharded Pub/Sub channel

        Returns:
            Dictionary of PubSub message attributes
        """
        attrs: Dict[str, Any] = AttributeBuilder.build_base_attributes()
        attrs[REDIS_CLIENT_PUBSUB_MESSAGE_DIRECTION] = direction.value

        if channel is not None:
            attrs[REDIS_CLIENT_PUBSUB_CHANNEL] = channel

        if sharded is not None:
            attrs[REDIS_CLIENT_PUBSUB_SHARDED] = sharded

        return attrs

    @staticmethod
    def build_streaming_attributes(
        stream_name: Optional[str] = None,
        consumer_group: Optional[str] = None,
        consumer_name: Optional[str] = None,  # noqa
    ) -> Dict[str, Any]:
        """
        Build attributes for a streaming operation.

        Args:
            stream_name: Name of the stream
            consumer_group: Name of the consumer group
            consumer_name: Name of the consumer

        Returns:
            Dictionary of streaming attributes
        """
        attrs: Dict[str, Any] = AttributeBuilder.build_base_attributes()

        if stream_name is not None:
            attrs[REDIS_CLIENT_STREAM_NAME] = stream_name

        if consumer_group is not None:
            attrs[REDIS_CLIENT_CONSUMER_GROUP] = consumer_group

        return attrs

    @staticmethod
    def build_csc_attributes(
        pool_name: Optional[str] = None,
        result: Optional[CSCResult] = None,
        reason: Optional[CSCReason] = None,
    ) -> Dict[str, Any]:
        """
        Build attributes for a Client Side Caching (CSC) operation.

        Args:
            pool_name: Connection pool name (used only for csc_items metric)
            result: CSC result ('hit' or 'miss')
            reason: Reason for CSC eviction ('full' or 'invalidation')

        Returns:
            Dictionary of CSC attributes
        """
        attrs: Dict[str, Any] = AttributeBuilder.build_base_attributes()

        if pool_name is not None:
            attrs[DB_CLIENT_CONNECTION_POOL_NAME] = pool_name

        if result is not None:
            attrs[REDIS_CLIENT_CSC_RESULT] = result.value

        if reason is not None:
            attrs[REDIS_CLIENT_CSC_REASON] = reason.value

        return attrs

    @staticmethod
    def build_geo_failover_attributes(
        fail_from: Union["SyncDatabase", "AsyncDatabase"],
        fail_to: Union["SyncDatabase", "AsyncDatabase"],
        reason: GeoFailoverReason,
    ) -> Dict[str, Any]:
        """
        Build attributes for a geo failover.

        Args:
            fail_from: Database failed from
            fail_to: Database failed to
            reason: Reason for the failover

        Returns:
            Dictionary of geo failover attributes
        """
        attrs: Dict[str, Any] = AttributeBuilder.build_base_attributes()

        attrs[DB_CLIENT_GEOFAILOVER_FAIL_FROM] = get_db_name(fail_from)
        attrs[DB_CLIENT_GEOFAILOVER_FAIL_TO] = get_db_name(fail_to)
        attrs[DB_CLIENT_GEOFAILOVER_REASON] = reason.value

        return attrs

    @staticmethod
    def build_pool_name(
        server_address: str,
        server_port: int,
        db_namespace: int = 0,
    ) -> str:
        """
        Build a unique connection pool name.

        Args:
            server_address: Redis server address
            server_port: Redis server port
            db_namespace: Redis database index

        Returns:
            Unique pool name in format "address:port/db"
        """
        return f"{server_address}:{server_port}/{db_namespace}"


def get_pool_name(pool: "ConnectionPoolInterface") -> str:
    """
    Get a short string representation of a connection pool for observability.

    This provides a concise pool identifier suitable for use as a metric attribute,
    in the format: host:port_uniqueID (matching go-redis format)

    Args:
        pool: Connection pool instance

    Returns:
        Short pool name in format "host:port_uniqueID"

    Example:
        >>> pool = ConnectionPool(host='localhost', port=6379, db=0)
        >>> get_pool_name(pool)
        'localhost:6379_a1b2c3d4'
    """
    host = pool.connection_kwargs.get("host", "unknown")
    port = pool.connection_kwargs.get("port", 6379)

    # Get unique pool ID if available (added for observability)
    pool_id = getattr(pool, "_pool_id", "")

    if pool_id:
        return f"{host}:{port}_{pool_id}"
    else:
        return f"{host}:{port}"


def get_db_name(database: Union["SyncDatabase", "AsyncDatabase"]):
    """
    Get a short string representation of a database for observability.

    Args:
        database: Database instance

    Returns:
        Short database name in format "{host}:{port}/{weight}"
    """

    host = database.client.get_connection_kwargs()["host"]
    port = database.client.get_connection_kwargs()["port"]
    weight = database.weight

    return f"{host}:{port}/{weight}"