import sys
import os
import re

def print_usage():
    print(f"usage: python {sys.argv[0]} DIR")
    print(f"")
    print(f"\tDIR\tdirectory containing markdown lists in files.")


if len(sys.argv) != 2:
    print_usage()
    exit(1)

base_path = os.path.abspath(sys.argv[1])
ready_list_name = "ready.md"
done_list_name = "all-done.md"

def get_path(list_name : str) -> str:
    return os.path.join(base_path, list_name)


def get_matches(list_name : str) -> list[re.Match]:
    # Matches a markdown list item
    entry_pattern = re.compile(r"^[*-] \[([ *x])\] (.+) - (.+)")

    matches = []
    with open(get_path(list_name)) as f:
        matches = [entry_pattern.match(l) for l in f.readlines()]
    return [m for m in matches if m is not None]


class Book:
    def __init__(self, match : re.Pattern):
        self.mark = match.group(1) != " "
        self.author = match.group(2)
        self.title = match.group(3)

    def is_metadata_complete(self):
        if not self.title or not self.author:
            return False

        if self.title == "???" or self.author == "???":
            return False

        return True

    @staticmethod
    def get_list(list_name : str, filter_partial_metadata = True) -> []:
        books = [Book(m) for m in get_matches(list_name)] 

        if filter_partial_metadata:
            books = [b for b in books if b.is_metadata_complete()]

        return books


def print_section(title : str, books : list[str]):
    print(f"# {title} ({len(books)})\n")

    longest_title = max([len(b.title) for b in books])
    title_column_width = longest_title + 2

    for book in books:
        row = [book.title, book.author]
        format_str = "- {: <" + str(title_column_width) + "} {: <20}"
        print(format_str.format(*row))
    print()

def print_in_progress():
    books = [b for b in Book.get_list(ready_list_name, False) if b.mark]
    print_section("in progress", books)

def print_completed():
    books = Book.get_list(done_list_name)
    print_section("up for borrowing", books)

def print_partial_metadata():
    books = Book.get_list(ready_list_name, False)
    books += Book.get_list(done_list_name, False)
    books = [b for b in books if not b.is_metadata_complete()]

    print_section("metadata incomplete", books)

print_in_progress()
print_completed()
print_partial_metadata()