import os
import mesop as me
from dataclasses import dataclass, field
from typing import Callable, Generator, Literal
import time
# from rag_app.rag import extract_final_answer, answer_question
from rag_app.rag_2 import check_if_exists, precompute_index, answer_question

Role = Literal["user", "assistant"]
_ROLE_USER = "user"
_ROLE_ASSISTANT = "assistant"

_COLOR_CHAT_BUBBLE_YOU = me.theme_var("surface-container-low")
_COLOR_CHAT_BUBBLE_BOT = me.theme_var("secondary-container")
_DEFAULT_BORDER_SIDE = me.BorderSide(
    width="1px", style="solid", color=me.theme_var("secondary-fixed")
)
_STYLE_CHAT_BUBBLE_NAME = me.Style(
    font_weight="bold",
    font_size="12px",
    padding=me.Padding(left=15, right=15, bottom=5),
)


@dataclass(kw_only=True)
class ChatMessage:
    role: Role = "user"
    content: str = ""


@me.stateclass
class State:
    input: str = ""
    output: list[ChatMessage] = field(default_factory=list)
    in_progress: bool = False
    pdf_files: list[str] = field(default_factory=list)  # Changed to a list


def respond_to_chat(query: str, history: list[ChatMessage]):
    # if not check_if_exists():
    #     print("computing the vector index and the BM 25 retriever which will later be used")
    #     precompute_index()
    
    assistant_message = ChatMessage(role=_ROLE_ASSISTANT)
    yield assistant_message
    state = me.state(State)
    if len(state.pdf_files) == 0:
        response = answer_question(query)
    else:
        response = answer_question(query)
        
    print("Agent response=", response)
    yield response
    

def on_chat_input(e: me.InputEvent):
    state = me.state(State)
    state.input = e.value


def on_click_submit_chat_msg(e: me.ClickEvent | me.InputEnterEvent):
    state = me.state(State)
    if state.in_progress or not state.input:
        return
    input_ = state.input
    state.input = ""
    yield
    
    output = state.output
    output.append(ChatMessage(role=_ROLE_USER, content=input_))
    state.in_progress = True
    me.scroll_into_view(key="scroll-to")
    yield
    
    start_time = time.time()
    for content in respond_to_chat(input_, state.output):
        if isinstance(content, ChatMessage):
            assistant_message = content
            output.append(assistant_message)
            state.output = output
        else:
            assistant_message.content += content
            if (time.time() - start_time) >= 0.25:
                start_time = time.time()
                yield
    
    state.in_progress = False
    yield


def _make_style_chat_bubble_wrapper(role: Role) -> me.Style:
    align_items = "end" if role == _ROLE_USER else "start"
    return me.Style(
        display="flex",
        flex_direction="column",
        align_items=align_items,
    )


def _make_chat_bubble_style(role: Role) -> me.Style:
    background = _COLOR_CHAT_BUBBLE_YOU
    if role == _ROLE_ASSISTANT:
        background = _COLOR_CHAT_BUBBLE_BOT
    return me.Style(
        width="80%",
        font_size="13px",
        background=background,
        border_radius="15px",
        padding=me.Padding(right=15, left=15, bottom=3),
        margin=me.Margin(bottom=10),
        border=me.Border(
            left=_DEFAULT_BORDER_SIDE,
            right=_DEFAULT_BORDER_SIDE,
            top=_DEFAULT_BORDER_SIDE,
            bottom=_DEFAULT_BORDER_SIDE,
        ),
    )


def save_uploaded_file(uploaded_file: me.UploadedFile):
    save_directory = "data"
    os.makedirs(save_directory, exist_ok=True)
    file_path = os.path.join(save_directory, uploaded_file.name)
    with open(file_path, "wb") as f:
        f.write(uploaded_file.getvalue())
    print(f"File saved successfully at {file_path}")
    

def handle_pdf_upload(event: me.UploadEvent):
    state = me.state(State)
    save_uploaded_file(event.file)
    print("precomputing vector indices")
    precompute_index()
    state.pdf_files.append(os.path.join("docs", event.file.name))