from pathlib import Path
from typing import Any

import aiofiles
from bs4 import BeautifulSoup, NavigableString, Tag


async def read_html(filename: Path) -> Tag | NavigableString | None:
    async with aiofiles.open(filename, "r") as f:
        html = await f.read()
        soup = BeautifulSoup(html, "html.parser")
        return soup.find("div", {"id": "premain"})


async def parse_html(data: Tag | NavigableString | None) -> dict[Any, Any]:
    result = {"f_x": await parse_x_coefficents(data)}
    result["tables"] = await parse_tables(data)

    return await modify_data(result)


async def parse_x_coefficents(data: Tag | NavigableString | None) -> list[Any]:
    if data is None:
        return []

    f_x = []
    b_el = data.find("b", string="Симплекс-метод")

    for _ in range(6):
        if b_el is not None:
            b_el = b_el.next_sibling

    if b_el is not None:
        f_x = ["".join(list(b_el.text.split()[-1])[:-1])]
        b_el = b_el.next_sibling

    while b_el is not None and b_el.text != " при следующих условиях-ограничений.":
        if b_el.text.endswith("x"):
            f_x.append((b_el.text[:-1]).replace("+", ""))

        b_el = b_el.next_sibling

    return f_x


async def parse_tables(data: Tag | NavigableString | None) -> dict[int, list[Any]]:
    if data is None:
        return {}

    tables = data.find_all("table", {"class": "table-bordered"})
    result = {}
    table_num = 0
    for table_idx in range(len(tables)):
        marked_ceil = False
        tmp_table = []
        for rows in tables[table_idx].find_all("tr"):
            tmp_row = []
            for col in rows.find_all("td"):
                if col.has_attr("bgcolor"):
                    marked_ceil = True
                    tmp_row.append((col.text, col["bgcolor"]))
                else:
                    tmp_row.append(col.text)
            tmp_table.append(tmp_row)

        if marked_ceil or table_idx == len(tables) - 1:
            result[table_num] = tmp_table

            table_num += 1

    return result


async def modify_data(data: dict[Any, Any]) -> dict[Any, Any]:
    for table in data["tables"].values():
        first_row = ["", "C", "-"] + data["f_x"]
        for _ in range(len(table[0]) - len(first_row) + 1):
            first_row.append("0")
        table.insert(0, first_row)

        for i in range(1, len(table)):
            f_ceil = table[i][0]
            (
                table[i].insert(0, "")
                if not f_ceil.startswith("x")
                else table[i].insert(0, first_row[int(f_ceil[1:]) + 2])
            )

    return data