from dataclasses import asdict
from operator import truth

from funcy import lmap, flatten

from cv_analysis.figure_detection.figure_detection import detect_figures
from cv_analysis.table_parsing import parse_tables
from cv_analysis.utils.rectangle import Rectangle
from pdf2img.conversion import convert_pages_to_images
from pdf2img.default_objects.image import ImagePlus, ImageInfo
from pdf2img.default_objects.rectangle import RectanglePlus


def make_analysis_pipeline_for_element_type(segment_type, **kwargs):
    if segment_type == "table":
        return make_analysis_pipeline(parse_tables, table_parsing_formatter, dpi=200, **kwargs)
    elif segment_type == "figure":
        return make_analysis_pipeline(detect_figures, figure_detection_formatter, dpi=200, **kwargs)
    else:
        raise ValueError(f"Unknown segment type {segment_type}.")


def make_analysis_pipeline(analysis_fn, formatter, dpi, skip_pages_without_images=False):
    def analysis_pipeline(pdf: bytes, index=None):
        def parse_page(page: ImagePlus):
            image = page.asarray()
            rectangles = analysis_fn(image)
            if not rectangles:
                return
            infos = formatter(rectangles, page, dpi)
            return infos

        pages = convert_pages_to_images(pdf, index=index, dpi=dpi, skip_pages_without_images=skip_pages_without_images)
        results = map(parse_page, pages)

        yield from flatten(filter(truth, results))

    return analysis_pipeline


def table_parsing_formatter(rectangles, page: ImagePlus, dpi):
    def format_rectangle(rectangle: Rectangle):
        rectangle_plus = RectanglePlus.from_pixels(*rectangle_to_xyxy(rectangle), page.info, alpha=False, dpi=dpi)
        return rectangle_plus.asdict(derotate=True)

    bboxes = lmap(format_rectangle, rectangles)

    return {"pageInfo": page.asdict(natural_index=True), "tableCells": bboxes}


def figure_detection_formatter(rectangles, page, dpi):
    def format_rectangle(rectangle: Rectangle):
        rect_plus = RectanglePlus.from_pixels(*rectangle_to_xyxy(rectangle), page.info, alpha=False, dpi=dpi)
        return asdict(ImageInfo(page.info, rect_plus.asbbox(derotate=False), rect_plus.alpha))

    return lmap(format_rectangle, rectangles)


def rectangle_to_xyxy(rectangle: Rectangle):
    return rectangle.x1, rectangle.y1, rectangle.x2, rectangle.y2