import os
from typing import Optional
import pandas as pd
from pdf2image import convert_from_path
from PIL import Image
from .config import settings
from striprtf.striprtf import rtf_to_text
from docx import Document


class FileProcessor:
    def __init__(self):
        pass

    def process_pdf(self, file_path: str) -> str:
        #list of images
        return convert_from_path(file_path)
    
    def process_image(self, file_path: str) -> str:
        return Image.open(file_path).convert('RGB')
    
    def process_doc(self, file_path: str) -> str:
        def split_doc(data: str) -> list:
            line_data = data.split('\n')
            line_count = len(line_data)
            #split by three
            split_len = line_count//3
            #split by 3 and also handle the case where the split is not even, so that the last one has the remaining lines
            doc_split = [line_data[i:i+split_len] for i in range(0, line_count, split_len)]
            #under each split, merge the line data into a single line
            doc_split = ['\n'.join(split) for split in doc_split]
            return doc_split

        if file_path.lower().endswith('.doc'):
            with open(file_path, "r", encoding='utf-8', errors='ignore') as file:
                data = rtf_to_text(file.read())
                if len(data.split('\n')) > 200:
                    split_data = split_doc(data)
                    return split_data
                else:
                    return data
        else:
            doc = Document(file_path)
            return '\n'.join([paragraph.text for paragraph in doc.paragraphs])
    
    def process_docx(self, file_path: str) -> str:
        doc = Document(file_path)
        return '\n'.join([paragraph.text for paragraph in doc.paragraphs])

    def process_xlsx(self, file_path: str) -> str:
        df = pd.read_excel(file_path)
        return df.to_string()

    def process_csv(self, file_path: str) -> str:
        df = pd.read_csv(file_path)
        return df.to_string()

    def process_txt(self, file_path: str) -> str:
        with open(file_path, 'r') as file:
            return file.read()

    def process_file(self, file_path: str) -> str:
        """Main method to process any supported file type."""
        _, file_extension = os.path.splitext(file_path)
        
        processors = {
            '.pdf': self.process_pdf,
            '.jpeg':self.process_image,
            '.jpg':self.process_image,
            '.png':self.process_image,
            '.doc': self.process_doc,
            '.docx': self.process_docx,
            '.xls': self.process_xlsx,
            '.xlsx': self.process_xlsx,
            '.csv': self.process_csv,
            '.txt': self.process_txt
        }
        
        processor = processors.get(file_extension.lower())
        if not processor:
            raise ValueError(f"Unsupported file format: {file_extension}")
            
        return processor(file_path)