import gradio  # for the interface
import transformers  # to load an LLM
import sentence_transformers  # to load an embedding model
import faiss  # to create an index
import numpy  # to work with vectors
import pandas  # to work with pandas
import json  # to work with JSON
import datasets  # to load the dataset
import spaces  # for GPU
import threading
import time

# Load the dataset and convert to pandas
full_data = datasets.load_dataset("ccm/publications")["train"].to_pandas()

# Filter out any publications without an abstract
filter = [
    '"abstract": null' in json.dumps(bibdict)
    for bibdict in full_data["bib_dict"].values
]
data = full_data[~pandas.Series(filter)]
data.reset_index(inplace=True)

# Create a FAISS index for fast similarity search
metric = faiss.METRIC_INNER_PRODUCT
vectors = numpy.stack(data["embedding"].tolist(), axis=0)
index = faiss.IndexFlatL2(len(data["embedding"][0]))
index.metric_type = metric
faiss.normalize_L2(vectors)
index.train(vectors)
index.add(vectors)

# Load the model for later use in embeddings
model = sentence_transformers.SentenceTransformer("allenai-specter")

# Define the search function
def search(query: str, k: int) -> tuple[str]:
    query = numpy.expand_dims(model.encode(query), axis=0)
    faiss.normalize_L2(query)
    D, I = index.search(query, k)
    top_five = data.loc[I[0]]

    search_results = "You are an AI assistant who delights in helping people" \
        + "learn about research from the Design Research Collective. Here are" \
        + "several really cool abstracts:\n\n"

    references = "\n\n## References\n\n"

    for i in range(k):
        search_results += top_five["bib_dict"].values[i]["abstract"] + "\n"
        references += str(i+1) + ". [" + top_five["bib_dict"].values[i]["title"] + "]" \
            + "(https://scholar.google.com/citations?view_op=view_citation&citation_for_view=" + top_five["author_pub_id"].values[i] + ")\n"

    search_results += "\nSummarize the above abstracts as you respond to the following query:"

    print(search_results)

    return search_results, references


# Create an LLM pipeline that we can send queries to
tokenizer = transformers.AutoTokenizer.from_pretrained("Qwen/Qwen2-0.5B-Instruct")
streamer = transformers.TextIteratorStreamer(tokenizer, skip_prompt=True, skip_special_tokens=True)
chatmodel = transformers.AutoModelForCausalLM.from_pretrained(
    "Qwen/Qwen2-0.5B-Instruct",
    torch_dtype="auto",
    device_map="auto"
)

def preprocess(message: str) -> tuple[str]:
    """Applies a preprocessing step to the user's message before the LLM receives it"""
    block_search_results, formatted_search_results = search(message, 5)
    return block_search_results + message, formatted_search_results

def postprocess(response: str, bypass_from_preprocessing: str) -> str:
    """Applies a postprocessing step to the LLM's response before the user receives it"""
    return response + bypass_from_preprocessing

@spaces.GPU
def predict(message: str, history: list[str]) -> str:
    """This function is responsible for crafting a response"""

    # Apply preprocessing
    message, bypass = preprocess(message)

    # This is some handling that is applied to the history variable to put it in a good format
    if isinstance(history, list):
        if len(history) > 0:
            history = history[-1]
    history_transformer_format = [
        {"role": "assistant" if idx&1 else "user", "content": msg}
        for idx, msg in enumerate(history)
    ] + [{"role": "user", "content": message}]

    # Stream a response from pipe
    text = tokenizer.apply_chat_template(
        history_transformer_format,
        tokenize=False,
        add_generation_prompt=True
    )
    model_inputs = tokenizer([text], return_tensors="pt").to("cuda:0")

    generate_kwargs = dict(
        model_inputs,
        streamer=streamer,
        max_new_tokens=512
    )
    t = threading.Thread(target=chatmodel.generate, kwargs=generate_kwargs)
    t.start()

    partial_message = ""
    for new_token in streamer:
        if new_token != '<':
            partial_message += new_token
            time.sleep(0.05)
            yield partial_message

    yield partial_message + bypass


# Create and run the gradio interface
gradio.ChatInterface(
    predict, 
    examples=[
        "Tell me about new research at the intersection of additive manufacturing and machine learning",
        "What is a physics-informed neural network and what can it be used for?",
        "What can agent-based models do about climate change?"
    ],
    chatbot = gradio.Chatbot(show_label=False),
    retry_btn = None,
    undo_btn = None,
    clear_btn=None,
    theme="monochrome",
    # cache_examples=True,
).launch(debug=True)