#!/usr/bin/env python3
# -*- encoding: utf-8 -*-

import csv
from io import StringIO
from typing import List, Optional, Tuple

import bs4

from .reader import AbstractReader
from .table import Table


class AbstractTableParser:
    def __init__(self, reader: AbstractReader):
        self._reader = reader
        self._read: Optional[str] = None

    def get_read(self) -> str:
        if self._read is None:
            self._read = self._reader.read()
        return self._read

    def parse(self, transpose: bool) -> Table:
        raise NotImplementedError()


class CsvTableParser(AbstractTableParser):
    def parse(self, transpose: bool) -> Table:
        mtx: List[List[str]] = list(csv.reader(StringIO(self.get_read())))
        tbl = [[(cell, '', '') for cell in line] for line in mtx]
        return Table(tbl)


class HtmlTableParser(AbstractTableParser):
    def _parse_tbl(self, tbl: bs4.element.Tag, transpose: bool) -> List[List[Tuple[str, str, str]]]:
        m = (
            [
                [
                    (
                        cell.get_text(separator=" \n", strip=True) or '',
                        (cell.select_one(
                            '[data-content]') or {'data-content': ''})['data-content'].strip(),
                        ''
                    ) for cell in row.find_all(['td', 'th'])
                ] for row in tbl.find_all('tr')
            ]
        )
        if transpose:
            m = list(map(list, zip(*m)))
        return m

    def parse(self, transpose: bool) -> Table:
        bs = bs4.BeautifulSoup(self.get_read(), 'html5lib')
        bstbl = bs.find('table')
        tbl = self._parse_tbl(bstbl, transpose)
        return Table(tbl)


class HtmlMultiTableParser(HtmlTableParser):
    def parse(self, transpose: bool) -> Table:
        bs = bs4.BeautifulSoup(self.get_read(), 'html5lib')
        tables: List[Table] = list()
        for bstbl in bs.find_all('table'):
            extra_context = list(filter(len, [
                x.get_text().strip()
                for x in bstbl.fetchPreviousSiblings()[::-1]
            ]))
            ecj = '\n'.join(extra_context)
            tbl = self._parse_tbl(bstbl, transpose)
            if len(ecj) > 0:
                tbl[1][0] = (f'{ecj} {tbl[1][0][0]}', tbl[1][0][1], '')
            tables.append(Table(tbl))
        return Table.merge_from(tables)