# Copyright (c) 2022-2024 Chris Pressey, Cat's Eye Technologies
# This file is distributed under a 2-clause BSD license.  See LICENSES directory:
# SPDX-License-Identifier: LicenseRef-BSD-2-Clause-X-Eqthy

import codecs
import os
import re
from typing import List, Tuple

from eqthy.objects import Document
from eqthy.parser import Parser


class Loader:
    def __init__(self, format: str):
        self.format = format

    def load(self, path: str) -> List[Document]:
        dirname, filename = os.path.split(path)
        return self.load_file_from_dir(dirname, filename)

    def load_file_from_dir(self, dirname: str, filename: str) -> List[Document]:
        path = os.path.join(dirname, filename)
        with codecs.open(path, 'r', encoding='UTF-8') as f:
            text = f.read()

        documents = []
        if self.format in "eqthy":
            pass
        elif self.format == "markdown":
            text, subdocs = self.extract_from_markdown(text, dirname)
            documents.extend(subdocs)
        else:
            raise NotImplementedError(self.format)

        p = Parser(text, filename)
        document = p.document()
        documents.append(document)
        return documents

    def extract_from_markdown(self, text: str, dirname: str) -> Tuple[str, List[Document]]:
        new_lines = []
        subdocs = []
        for line in text.split("\n"):
            if line.startswith("    "):
                new_lines.append(line[4:])
            else:
                match = re.match(r'^Requires \[.*?\]\((.*?)\).*?$', line, re.IGNORECASE)
                if match:
                    subdocs = self.load_file_from_dir(dirname, match.group(1))
        return "\n".join(new_lines), subdocs