import logging
import os
from collections.abc import AsyncIterator
from typing import Any

import numpy as np
import pipmaster as pm  # Pipmaster for dynamic library install

from lightrag.utils import VERBOSE_DEBUG, verbose_debug

# Install Anthropic SDK if not present
if not pm.is_installed('anthropic'):
    pm.install('anthropic')

# Add Voyage AI import
if not pm.is_installed('voyageai'):
    pm.install('voyageai')
import voyageai
from anthropic import (
    APIConnectionError,
    APITimeoutError,
    AsyncAnthropic,
    RateLimitError,
)
from tenacity import (
    retry,
    retry_if_exception_type,
    stop_after_attempt,
    wait_exponential,
)

from lightrag.api import __api_version__
from lightrag.utils import (
    logger,
    safe_unicode_decode,
)


# Custom exception for retry mechanism
class InvalidResponseError(Exception):
    """Custom exception class for triggering retry mechanism"""

    pass


# Core Anthropic completion function with retry
@retry(
    stop=stop_after_attempt(3),
    wait=wait_exponential(multiplier=1, min=4, max=10),
    retry=retry_if_exception_type((RateLimitError, APIConnectionError, APITimeoutError, InvalidResponseError)),
)
async def anthropic_complete_if_cache(
    model: str,
    prompt: str,
    system_prompt: str | None = None,
    history_messages: list[dict[str, Any]] | None = None,
    enable_cot: bool = False,
    base_url: str | None = None,
    api_key: str | None = None,
    **kwargs: Any,
) -> str | AsyncIterator[str]:
    if history_messages is None:
        history_messages = []
    if enable_cot:
        logger.debug('enable_cot=True is not supported for the Anthropic API and will be ignored.')
    if not api_key:
        api_key = os.environ.get('ANTHROPIC_API_KEY')

    default_headers = {
        'User-Agent': f'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_8) LightRAG/{__api_version__}',
        'Content-Type': 'application/json',
    }

    # Set logger level to INFO when VERBOSE_DEBUG is off
    if not VERBOSE_DEBUG and logger.level == logging.DEBUG:
        logging.getLogger('anthropic').setLevel(logging.INFO)

    kwargs.pop('hashing_kv', None)
    kwargs.pop('keyword_extraction', None)
    timeout = kwargs.pop('timeout', None)

    anthropic_async_client = (
        AsyncAnthropic(default_headers=default_headers, api_key=api_key, timeout=timeout)
        if base_url is None
        else AsyncAnthropic(
            base_url=base_url,
            default_headers=default_headers,
            api_key=api_key,
            timeout=timeout,
        )
    )

    messages: list[dict[str, Any]] = []
    if system_prompt:
        messages.append({'role': 'system', 'content': system_prompt})
    messages.extend(history_messages)
    messages.append({'role': 'user', 'content': prompt})

    logger.debug('===== Sending Query to Anthropic LLM =====')
    logger.debug(f'Model: {model}   Base URL: {base_url}')
    logger.debug(f'Additional kwargs: {kwargs}')
    verbose_debug(f'Query: {prompt}')
    verbose_debug(f'System prompt: {system_prompt}')

    try:
        response = await anthropic_async_client.messages.create(model=model, messages=messages, stream=True, **kwargs)
    except APIConnectionError as e:
        logger.error(f'Anthropic API Connection Error: {e}')
        raise
    except RateLimitError as e:
        logger.error(f'Anthropic API Rate Limit Error: {e}')
        raise
    except APITimeoutError as e:
        logger.error(f'Anthropic API Timeout Error: {e}')
        raise
    except Exception as e:
        logger.error(f'Anthropic API Call Failed,\nModel: {model},\nParams: {kwargs}, Got: {e}')
        raise

    async def stream_response():
        try:
            async for event in response:
                content = event.delta.text if hasattr(event, 'delta') and event.delta.text else None
                if content is None:
                    continue
                if r'\u' in content:
                    content = safe_unicode_decode(content.encode('utf-8'))
                yield content
        except Exception as e:
            logger.error(f'Error in stream response: {e!s}')
            raise

    return stream_response()


# Generic Anthropic completion function
async def anthropic_complete(
    prompt: str,
    system_prompt: str | None = None,
    history_messages: list[dict[str, Any]] | None = None,
    enable_cot: bool = False,
    **kwargs: Any,
) -> str | AsyncIterator[str]:
    if history_messages is None:
        history_messages = []
    model_name = kwargs['hashing_kv'].global_config['llm_model_name']
    return await anthropic_complete_if_cache(
        model_name,
        prompt,
        system_prompt=system_prompt,
        history_messages=history_messages,
        enable_cot=enable_cot,
        **kwargs,
    )


# Claude 3 Opus specific completion
async def claude_3_opus_complete(
    prompt: str,
    system_prompt: str | None = None,
    history_messages: list[dict[str, Any]] | None = None,
    enable_cot: bool = False,
    **kwargs: Any,
) -> str | AsyncIterator[str]:
    if history_messages is None:
        history_messages = []
    return await anthropic_complete_if_cache(
        'claude-3-opus-20240229',
        prompt,
        system_prompt=system_prompt,
        history_messages=history_messages,
        enable_cot=enable_cot,
        **kwargs,
    )


# Claude 3 Sonnet specific completion
async def claude_3_sonnet_complete(
    prompt: str,
    system_prompt: str | None = None,
    history_messages: list[dict[str, Any]] | None = None,
    enable_cot: bool = False,
    **kwargs: Any,
) -> str | AsyncIterator[str]:
    if history_messages is None:
        history_messages = []
    return await anthropic_complete_if_cache(
        'claude-3-sonnet-20240229',
        prompt,
        system_prompt=system_prompt,
        history_messages=history_messages,
        enable_cot=enable_cot,
        **kwargs,
    )


# Claude 3 Haiku specific completion
async def claude_3_haiku_complete(
    prompt: str,
    system_prompt: str | None = None,
    history_messages: list[dict[str, Any]] | None = None,
    enable_cot: bool = False,
    **kwargs: Any,
) -> str | AsyncIterator[str]:
    if history_messages is None:
        history_messages = []
    return await anthropic_complete_if_cache(
        'claude-3-haiku-20240307',
        prompt,
        system_prompt=system_prompt,
        history_messages=history_messages,
        enable_cot=enable_cot,
        **kwargs,
    )


# Embedding function (placeholder, as Anthropic does not provide embeddings)
@retry(
    stop=stop_after_attempt(3),
    wait=wait_exponential(multiplier=1, min=4, max=60),
    retry=retry_if_exception_type((RateLimitError, APIConnectionError, APITimeoutError)),
)
async def anthropic_embed(
    texts: list[str],
    model: str = 'voyage-3',  # Default to voyage-3 as a good general-purpose model
    base_url: str | None = None,
    api_key: str | None = None,
) -> np.ndarray:
    """
    Generate embeddings using Voyage AI since Anthropic doesn't provide native embedding support.

    Args:
        texts: List of text strings to embed
        model: Voyage AI model name (e.g., "voyage-3", "voyage-3-large", "voyage-code-3")
        base_url: Optional custom base URL (not used for Voyage AI)
        api_key: API key for Voyage AI (defaults to VOYAGE_API_KEY environment variable)

    Returns:
        numpy array of shape (len(texts), embedding_dimension) containing the embeddings
    """
    if not api_key:
        api_key = os.environ.get('VOYAGE_API_KEY')
        if not api_key:
            logger.error('VOYAGE_API_KEY environment variable not set')
            raise ValueError('VOYAGE_API_KEY environment variable is required for embeddings')

    try:
        # Initialize Voyage AI client
        voyage_client = voyageai.Client(api_key=api_key)

        # Get embeddings
        result = voyage_client.embed(
            texts,
            model=model,
            input_type='document',  # Assuming document context; could be made configurable
        )

        # Convert list of embeddings to numpy array
        embeddings = np.array(result.embeddings, dtype=np.float32)

        logger.debug(f'Generated embeddings for {len(texts)} texts using {model}')
        verbose_debug(f'Embedding shape: {embeddings.shape}')

        return embeddings

    except Exception as e:
        logger.error(f'Voyage AI embedding failed: {e!s}')
        raise


# Optional: a helper function to get available embedding models
def get_available_embedding_models() -> dict[str, dict]:
    """
    Returns a dictionary of available Voyage AI embedding models and their properties.
    """
    return {
        'voyage-3-large': {
            'context_length': 32000,
            'dimension': 1024,
            'description': 'Best general-purpose and multilingual',
        },
        'voyage-3': {
            'context_length': 32000,
            'dimension': 1024,
            'description': 'General-purpose and multilingual',
        },
        'voyage-3-lite': {
            'context_length': 32000,
            'dimension': 512,
            'description': 'Optimized for latency and cost',
        },
        'voyage-code-3': {
            'context_length': 32000,
            'dimension': 1024,
            'description': 'Optimized for code',
        },
        'voyage-finance-2': {
            'context_length': 32000,
            'dimension': 1024,
            'description': 'Optimized for finance',
        },
        'voyage-law-2': {
            'context_length': 16000,
            'dimension': 1024,
            'description': 'Optimized for legal',
        },
        'voyage-multimodal-3': {
            'context_length': 32000,
            'dimension': 1024,
            'description': 'Multimodal text and images',
        },
    }