"""
Two-agent system to use to chat with multiple docs,
and use a combination of Filtering + RAG to answer questions,
where the filter is manually set via the LanceDocChatAgentConfig.filter field.

Works with LanceDB vector-db.

- Main agent takes user question, generates a QueryPlan consisting of
    - filter (SQL, to use with lanceDB)
    - possibly rephrased query

See here for how to set up a Local LLM to work with Langroid:
https://langroid.github.io/langroid/tutorials/local-llm-setup/

NOTES:
(1) The app works best with GPT4/Turbo, but results may be mixed with local LLMs.
You may have to tweak the system_message, use_message, and summarize_prompt
as indicated in comments below, to get good results.

"""

import os

import typer
from rich import print
from rich.prompt import Prompt

import langroid as lr
import langroid.language_models as lm
from langroid.agent.special.doc_chat_agent import DocChatAgentConfig
from langroid.agent.special.lance_doc_chat_agent import LanceDocChatAgent
from langroid.embedding_models.models import OpenAIEmbeddingsConfig
from langroid.parsing.parser import ParsingConfig, PdfParsingConfig, Splitter
from langroid.pydantic_v1 import Field
from langroid.utils.configuration import Settings, set_global
from langroid.vector_store.lancedb import LanceDBConfig

app = typer.Typer()

os.environ["TOKENIZERS_PARALLELISM"] = "false"


class MusicianMetadata(lr.DocMetaData):
    name: str = Field(..., description="The name of the musician.")
    birth_year: int = Field(..., description="The year the musician was born.")
    death_year: int = Field(..., description="The year the musician died.")
    type: str = Field(..., description="The type of musician, e.g. composer, musician.")
    genre: str = Field(..., description="The genre of the musician.")


class MusicianDocument(lr.Document):
    content: str
    metadata: MusicianMetadata


@app.command()
def main(
    debug: bool = typer.Option(False, "--debug", "-d", help="debug mode"),
    nocache: bool = typer.Option(False, "--nocache", "-nc", help="don't use cache"),
    model: str = typer.Option("", "--model", "-m", help="model name"),
) -> None:
    llm_config = lm.OpenAIGPTConfig(
        chat_model=model or lm.OpenAIChatModel.GPT4o,
        # or, other possibilities for example:
        # "litellm/bedrock/anthropic.claude-instant-v1"
        # "ollama/llama2"
        # "local/localhost:8000/v1"
        # "local/localhost:8000"
        chat_context_length=4096,  # adjust based on model
        timeout=90,
    )

    # Configs
    embed_cfg = OpenAIEmbeddingsConfig()

    # Get movies data
    COLLECTION = "chat-lance-music"
    ldb_dir = ".lancedb/data/musicians"
    ldb_cfg = LanceDBConfig(
        cloud=False,
        collection_name=COLLECTION,
        storage_path=ldb_dir,
        embedding=embed_cfg,
        replace_collection=False,
        document_class=MusicianDocument,
    )
    config = DocChatAgentConfig(
        name="MusicianBot",
        vecdb=ldb_cfg,
        n_query_rephrases=0,
        hypothetical_answer=False,
        # set it to > 0 to retrieve a window of k chunks on either side of a match
        n_neighbor_chunks=0,
        n_similar_chunks=3,
        n_relevant_chunks=3,
        llm=llm_config,
        # system_message="...override default DocChatAgent system msg here",
        # user_message="...override default DocChatAgent user msg here",
        # summarize_prompt="...override default DocChatAgent summarize prompt here",
        parsing=ParsingConfig(  # modify as needed
            splitter=Splitter.TOKENS,
            chunk_size=300,  # aim for this many tokens per chunk
            overlap=30,  # overlap between chunks
            max_chunks=10_000,
            n_neighbor_ids=5,  # store ids of window of k chunks around each chunk.
            # aim to have at least this many chars per chunk when
            # truncating due to punctuation
            min_chunk_chars=200,
            discard_chunk_chars=5,  # discard chunks with fewer than this many chars
            # NOTE: PDF parsing is extremely challenging, each library has its own
            # strengths and weaknesses. Try one that works for your use case.
            pdf=PdfParsingConfig(
                # alternatives: "unstructured", "docling", "fitz"
                library="pymupdf4llm",
            ),
        ),
    )

    set_global(
        Settings(
            debug=debug,
            cache=not nocache,
            cache_type="fakeredis",
        )
    )

    print("[blue]Welcome to the Musician document-filtering chatbot!")

    # need a LanceDocChatAgent to use LanceRAgTaskCreator below
    agent = LanceDocChatAgent(config)

    # INGEST DOCS with META DATA
    beethoven_path = (
        "https://en.wikipedia.org/wiki/Ludwig_van_Beethoven"  # or can be local dir
    )
    mozart_path = "https://en.wikipedia.org/wiki/Wolfgang_Amadeus_Mozart"
    bach_path = "https://en.wikipedia.org/wiki/Johann_Sebastian_Bach"
    hendrix_path = "https://en.wikipedia.org/wiki/Pink_Floyd"
    prince_path = "https://en.wikipedia.org/wiki/Prince_(musician)"
    jackson_path = "https://en.wikipedia.org/wiki/Michael_Jackson"

    paths = dict(
        beethoven=beethoven_path,
        mozart=mozart_path,
        bach=bach_path,
        hendrix=hendrix_path,
        prince=prince_path,
        jackson=jackson_path,
    )

    metadata = dict(
        beethoven=MusicianMetadata(
            name="Beethoven",
            birth_year=1770,
            death_year=1827,
            type="composer",
            genre="classical",
        ),
        mozart=MusicianMetadata(
            name="Mozart",
            birth_year=1756,
            death_year=1791,
            type="composer",
            genre="classical",
        ),
        bach=MusicianMetadata(
            name="Bach",
            birth_year=1685,
            death_year=1750,
            type="composer",
            genre="classical",
        ),
        hendrix=MusicianMetadata(
            name="Hendrix",
            birth_year=1942,
            death_year=1970,
            type="musician",
            genre="rock",
        ),
        prince=MusicianMetadata(
            name="Prince",
            birth_year=1958,
            death_year=2016,
            type="musician",
            genre="rock",
        ),
        jackson=MusicianMetadata(
            name="Jackson",
            birth_year=1958,
            death_year=2009,
            type="musician",
            genre="pop",
        ),
    )

    create_collection = True
    if COLLECTION in agent.vecdb.list_collections():
        replace = Prompt.ask(
            f"Collection {COLLECTION} already exists. Replace it? (y/n)",
            choices=["y", "n"],
            default="n",
        )
        if replace == "y":
            agent.vecdb.set_collection(COLLECTION, replace=True)
        else:
            create_collection = False
    if create_collection:
        print("[blue]Ingesting docs...")
        for musician in metadata:
            agent.ingest_doc_paths(
                [paths[musician]],  # all chunks of this doc will have same metadata
                metadata[musician],
            )
        print("[blue]Done ingesting docs")

    musician = Prompt.ask(
        "[blue]which musician would you like to ask about?",
        choices=list(metadata.keys()),
        default="beethoven",
    )
    print(f"[blue]You chose {metadata[musician].name}")
    # this filter setting will be used by the LanceDocChatAgent
    # to restrict the docs searched from the vector-db
    config.filter = f"metadata.name = '{metadata[musician].name}'"

    print("[blue]Reqdy for your questions...")
    task = lr.Task(
        agent,
        interactive=True,
    )
    task.run("Can you help me with some questions about musicians?")


if __name__ == "__main__":
    app()
