# imports
from abc import ABC, abstractmethod
from typing import Optional, Union, Sequence, Dict, Mapping, List, Any
from typing_extensions import TypedDict
from chroma_datasets.types import AddEmbedding, Datapoint
from chroma_datasets.utils import load_huggingface_dataset, to_chroma_schema
from chromadb.utils import embedding_functions
import os
from dotenv import load_dotenv

HF_API_KEY = os.environ.get("HF_API_KEY")

ef_instruction_dict = {
    "HuggingFaceEmbeddingFunction": """
        from chromadb.utils import embedding_functions
        hf_ef = embedding_functions.huggingface_embedding_function.HuggingFaceEmbeddingFunction(api_key={HF_API_KEY}, model_name="mixedbread-ai/mxbai-embed-large-v1")
        
    """
}

class Dataset(ABC):
    """
        Abstract class for a dataset

        All datasets should inherit from this class

        Properties:
            hf_data: the raw data from huggingface
            embedding_function: the embedding function used to generate the embeddings
            embeddingFunctionInstructions: tell the user how to set up the embedding function
    """
    hf_dataset_name: str
    hf_data: Any
    embedding_function: str
    embedding_function_instructions: str

    @classmethod
    def load_data(cls):
        cls.hf_data = load_huggingface_dataset(
            cls.hf_dataset_name,
            split_name="data"
        )

    @classmethod
    def raw_text(cls) -> str:
        if cls.hf_data is None:
            cls.load_data()
        return "\n".join(cls.hf_data["document"])
    
    @classmethod
    def chunked(cls) -> List[Datapoint]:
        if cls.hf_data is None:
            cls.load_data()
        return cls.hf_data
    
    @classmethod
    def to_chroma(cls) -> AddEmbedding:
        return to_chroma_schema(cls.chunked())
    

class Memoires_DS(Dataset):
    """
    """
    hf_data = None
    hf_dataset_name = "eliot-hub/memoires_vec_800"
    embedding_function = "HuggingFaceEmbeddingFunction"
    embedding_function_instructions = ef_instruction_dict[embedding_function]




def import_into_chroma(chroma_client, dataset, collection_name=None, embedding_function=None, batch_size=5000):
    """
    Imports a dataset into Chroma in batches.

    Args:
        chroma_client (ChromaClient): The ChromaClient to use.
        collection_name (str): The name of the collection to load the dataset into.
        dataset (AddEmbedding): The dataset to load.
        embedding_function (Optional[Callable[[str], np.ndarray]]): A function that takes a string and returns an embedding.
        batch_size (int): The size of each batch to load.
    """
    # if chromadb is not installed, raise an error
    try:
        import chromadb
        from chromadb.utils import embedding_functions
    except ImportError:
        raise ImportError("Please install chromadb to use this function. `pip install chromadb`")

    ef = None

    if dataset.embedding_function is not None:
        if embedding_function is None:
            error_msg = "See documentation"
            if dataset.embedding_function_instructions is not None:
                error_msg = dataset.embedding_function_instructions

            raise ValueError(f"""
                             Dataset requires embedding function: {dataset.embedding_function}.
                             {error_msg}
                             """)

        if embedding_function.__class__.__name__ != dataset.embedding_function:
            raise ValueError(f"Please use {dataset.embedding_function} as the embedding function for this dataset. You passed {embedding_function.__class__.__name__}")

    if embedding_function is not None:
        ef = embedding_function

    # if collection_name is None, get the name from the dataset type 
    if collection_name is None:
        collection_name = dataset.__name__

    if ef is None:
        ef = embedding_functions.DefaultEmbeddingFunction()

    print("########### Init collection ###########")
    collection = chroma_client.create_collection(
        collection_name,
        embedding_function=ef
    )

    # Retrieve the mapped data
    print("########### Init to_chroma ###########")
    mapped_data = dataset.to_chroma()
    del dataset
    
    # Split the data into batches and add them to the collection
    def chunk_data(data, size):
        """Helper function to split data into batches."""
        for i in range(0, len(data), size):
            yield data[i:i+size]

    print("########### Chunking ###########")
    ids_batches = list(chunk_data(mapped_data["ids"], batch_size))
    metadatas_batches = list(chunk_data(mapped_data["metadatas"], batch_size))
    documents_batches = list(chunk_data(mapped_data["documents"], batch_size))
    embeddings_batches = list(chunk_data(mapped_data["embeddings"], batch_size))

    total_docs = len(mapped_data["ids"])

    print("########### Iterating batches ###########")
    for i, (ids, metadatas, documents, embeddings) in enumerate(zip(ids_batches, metadatas_batches, documents_batches, embeddings_batches)):
        collection.add(
            ids=ids,
            metadatas=metadatas,
            documents=documents,
            embeddings=embeddings,
        )
        print(f"Batch {i+1}/{len(ids_batches)}: Loaded {len(ids)} documents.")

    print(f"Successfully loaded {total_docs} documents into the collection named: {collection_name}")
    

    return collection