from langchain_core.messages import SystemMessage
from .tools import retrieve_tool
import base64
from PIL import Image
from io import BytesIO
from fastapi import UploadFile
from huggingface_hub import InferenceClient
from .prompts import story_to_prompt , final_story_prompt
import os
from langgraph.prebuilt import create_react_agent
import pandas as pd
from datasets import load_dataset
import ast
import faiss
import re
import numpy as np
from utils.models_loader import ST , llm



def generate_final_story(final_state):
    if len(final_state['preferred_topics'])>0:
        template = final_story_prompt(final_state)
        messages = [SystemMessage(content=template)]

        tools = [retrieve_tool]
        react_agent=create_react_agent(
        model=llm.bind_tools(tools),
        tools=tools)

        response = react_agent.invoke({'messages':messages})
        response = response['messages'][-1].content
        return response
    
    else:
        return final_state['stories'][-1]



def encode_image_to_base64(uploaded_file: UploadFile) -> str:
    return base64.b64encode(uploaded_file.file.read()).decode("utf-8")
  

# Convert base64 string to PIL image (optional for LangGraph processing)
def process_image(base64_str: str) -> Image.Image:
    image_data = base64.b64decode(base64_str)
    return Image.open(BytesIO(image_data))


def generate_prompt(final_story):
    print('************Entering prompt generator****************')
    messages = [
    (
        "system",
        story_to_prompt,
    ),
    ("human", final_story),
]
    prompt = llm.invoke(messages)
    print('The prompt is:',prompt)
    return prompt.content

def generate_image(final_story):
    prompt = generate_prompt(final_story)
    print('************Finished prompt generator****************')

    client = InferenceClient(
        provider="hf-inference",
        api_key=os.environ.get('HUGGINGFACEHUB_ACCESS_TOKEN'),
    )

    print('************Finished calling generator****************')


        # output is a PIL.Image object
    image = client.text_to_image(
        prompt,
        model="black-forest-labs/FLUX.1-schnell",
    )
    print('*****************Image Created*******************')

    image.save('image.png')
    print('*****************Image Saved*******************')
    return "Image Created"


def save_to_db(business_details):
    dataset = load_dataset("subashdvorak/tiktok-agentic-story")['train']
    # dataset = load_influencer_data()
    df = pd.DataFrame(dataset)

    # 2. Flatten all business detail values to a set of lowercase strings
    all_values = set()
    for v in business_details.values():
        if isinstance(v, str):
            all_values.add(v.lower())
        elif isinstance(v, list):
            all_values.update(map(str.lower, map(str, v)))

    # 3. Match rows where ANY column contains ANY of the values
    def row_matches(row):
        return any(
            str(cell).lower().find(val) != -1
            for cell in row
            for val in all_values
        )

    # 4. Apply row-wise matching
    matched_df = df[df.apply(row_matches, axis=1)]
    matched_df.to_csv('extracted_data.csv')

def manual_retrieval(messages, business_details):
    # === Load CSV ===
    csv_path = 'extracted_data.csv'
    df = pd.read_csv(csv_path)

    # === Parse stored embeddings ===
    df['embeddings'] = df['embeddings'].apply(lambda x: ast.literal_eval(x) if isinstance(x, str) else x)
    embeddings = np.vstack(df['embeddings'].values).astype('float32')

    # === Build FAISS index ===
    dimension = embeddings.shape[1]
    index = faiss.IndexFlatL2(dimension)
    index.add(embeddings)

    # === Load SentenceTransformer model ===

    # === Encode the query and search ===
    query_embedding = ST.encode(str(messages)+str(business_details)).reshape(1, -1).astype('float32')
    top_k=3
    distances, indices = index.search(query_embedding, top_k)

    # === Function to extract sections 1 and 6 ===
    def extract_story_and_branding(full_story):
        full_story = full_story.replace('**6. Visible Texts or Brandings**', '**6. Visible Texts or Brandings:**')
        full_story = full_story.replace('**1. Story**', '**1. Story:**')

        pattern = (
            r"\*\*1\. Story:\*\*(.*?)(?=\*\*\d+\.\s)"
            r".*?"
            r"\*\*6\. Visible Texts or Brandings:\*\*(.*?)(?=\*\*\d+\.\s|$)"
        )
        match = re.search(pattern, full_story, re.DOTALL)
        if match:
            story_section = match.group(1).strip()
            branding_section = match.group(2).strip()
            return f"Story:\n{story_section}\n\nVisible Texts or Brandings:\n{branding_section}"
        else:
            return "Requested sections not found."

    # === Format results ===
    outer_list = []
    for i, idx in enumerate(indices[0]):
        res = {
            'rank': i + 1,
            'username': df.iloc[idx]['username'],
            'agentic_story': df.iloc[idx]['agentic_story'],
            'likesCount': df.iloc[idx]['likesCount'],
            'commentCount': df.iloc[idx]['commentCount'],
            'distance': distances[0][i]
        }

        inner_list = []
        inner_list.append(f"[{res['rank']}]. The influencer name is: **{res['username']}** — Likes: **{res['likesCount']}**, Comments: **{res['commentCount']}**")
        inner_list.append(f"The story of that particular video is:\n{extract_story_and_branding(res['agentic_story'])}")
        inner_list.append(f"Distance: {res['distance']:.4f}")
        outer_list.append(inner_list)

    return str(outer_list)