from io import BytesIO

import fitz
import pdfrw
from fpdf import FPDF


class PdfMaker:
    def __init__(self, size: tuple):
        self.size = size

        self.writer = pdfrw.PdfWriter()

    def clear(self):
        del self.writer
        self.writer = pdfrw.PdfWriter()

    def add_image(self, image_data):
        size = self.size

        fpdf = FPDF(format=size, unit="pt")
        width, height = self.size
        fpdf.add_page()
        fpdf.image(image_data, 0, 0, width, height)
        fpdf_reader: pdfrw.PdfReader = pdfrw.PdfReader(fdata=bytes(fpdf.output()))
        self.writer.addpage(fpdf_reader.getPage(0))

    def add_pdf(self, pdf_data: BytesIO):
        pdf_reader = pdfrw.PdfReader(fdata=bytes(pdf_data.read()))
        self.writer.addpage(pdf_reader.getPage(0))

    def add_pdfs(self, pdf_data: BytesIO):
        pdf_reader = pdfrw.PdfReader(fdata=bytes(pdf_data.read()))
        self.writer.addpages(pdf_reader.readpages(pdf_reader.Root))

    def get_bytes(self):
        result_io = BytesIO()
        self.writer.write(result_io)
        result_io.seek(0)
        return result_io

    @staticmethod
    def _get_target_rect(page: fitz.Page, target_ratio: float) -> fitz.Rect:
        original_width, original_height = page.rect.width, page.rect.height

        if original_width / original_height > target_ratio:
            # Image is wider than target aspect ratio
            new_width = original_width
            new_height = int(original_width / target_ratio)
        else:
            # Image is taller than target aspect ratio
            new_height = original_height
            new_width = int(new_height * target_ratio)

        return fitz.Rect(0, 0, new_width, new_height)

    @staticmethod
    def resize_pdf_with_reportlab(input_pdf_bytesio: BytesIO) -> BytesIO:
        output_pdf = BytesIO()

        pdf_document = fitz.open(stream=input_pdf_bytesio.getvalue(), filetype="pdf")

        if len(pdf_document) != 1:
            raise Exception("Ошибка. В документе должна быть одна страница.")

        page = pdf_document[0]
        target_ratio = 29 / 20
        actual_ratio = page.rect.width / page.rect.height

        if abs(actual_ratio - target_ratio) < 0.1:
            return input_pdf_bytesio

        rect = PdfMaker._get_target_rect(page, target_ratio)
        page.set_mediabox(rect)
        page.set_cropbox(rect)
        page.set_bleedbox(rect)
        page.set_trimbox(rect)

        pdf_document.save(output_pdf)
        pdf_document.close()

        output_pdf.seek(0)
        return output_pdf