Major refactor: breakdown epy.py script

into package project structure for easier
development
Squashed commit of the following:

commit 01309b961a4ab32394bff0d90949b57435dfda47
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sun Oct 2 21:15:04 2022 +0700

    Fix missing objects

commit aab2e773c30b255c81b1250b3b20967d5da40338
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sun Oct 2 21:09:31 2022 +0700

    Update README.md

commit d4e98926bcd9b00ce0410ad71249d24e6315abc5
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sun Oct 2 21:07:28 2022 +0700

    Add keywords in pyproject.toml

commit 432055af8245560a3ff2e046aef0b4e87da44930
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sun Oct 2 21:04:34 2022 +0700

    Bump version and deprecete setup.py

commit 51dd15aab8f8ff5996f822f8378e813f0b9fb80d
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sun Oct 2 20:56:38 2022 +0700

    Formatting

commit 81fb35e3b6fa0e27d79ef1da77202ed81eb99500
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sun Oct 2 20:55:08 2022 +0700

    Fix speakers module

commit 3b852e7c59b38d5a28520038e35f50a95270d2f1
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sat Oct 1 20:52:46 2022 +0700

    Fix circular import

commit 061e8a2649dabacd28a9e2f972559475316c654c
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sat Oct 1 20:39:27 2022 +0700

    Run formatting

commit abc2d0ab156992c63dc04745d14a69679a60accb
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sat Oct 1 20:39:00 2022 +0700

    Update isort and black config in pyproject

commit 5dc2e41bab5b997bd719bdc1561eb51ba0c17a83
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sat Oct 1 20:31:00 2022 +0700

    Add app Config

commit ed485a2ea8281585bf86dc5772f0c6dd9c803cc4
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sat Oct 1 20:23:02 2022 +0700

    Update debugpy script

commit 68b0553dd4d63eb4b847132c68ea4018587fa8ec
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sat Oct 1 20:14:11 2022 +0700

    Connect reader to main script

commit 63c3dd176f18a784a4ed2e88aa72b13d1c2b0990
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sat Oct 1 20:11:17 2022 +0700

    Implement reader

commit ce5eec8fb4e1db3870a16a07541365cd777d6c4c
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sat Oct 1 19:29:49 2022 +0700

    Fix script in pyproject.toml

commit 941e8e49f1593731fb582d92084206772b3f0442
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sat Oct 1 19:28:39 2022 +0700

    Rename modules

commit 5a3e7f766aee774c09b3b5336f3a2968e9cb1d0c
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sat Oct 1 19:28:20 2022 +0700

    Rename tool method

commit 3c0503ff475cb7eff8b12d3be0bda7a38efe1072
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sat Oct 1 19:27:03 2022 +0700

    Add ebooks lib

commit b5f71c3296a7d6f36454f6e1cbe84e15a45092ee
Author: Benawi Adha <benawiadha@gmail.com>
Date:   Sat Oct 1 17:25:11 2022 +0700

    Initial reorganization

1 files changed, 232 insertions, 0 deletions

diff --git a/src/epy_reader/models.py b/src/epy_reader/models.py
new file mode 100644
index 0000000..db4701b
--- /dev/null
+++ b/src/epy_reader/models.py
@@ -0,0 +1,232 @@
+import os
+from dataclasses import dataclass
+from datetime import datetime
+from enum import Enum
+from typing import Any, Mapping, Optional, Tuple, Union
+
+
+class Direction(Enum):
+    FORWARD = "forward"
+    BACKWARD = "backward"
+
+
+@dataclass(frozen=True)
+class BookMetadata:
+    title: Optional[str] = None
+    creator: Optional[str] = None
+    description: Optional[str] = None
+    publisher: Optional[str] = None
+    date: Optional[str] = None
+    language: Optional[str] = None
+    format: Optional[str] = None
+    identifier: Optional[str] = None
+    source: Optional[str] = None
+
+
+@dataclass(frozen=True)
+class LibraryItem:
+    last_read: datetime
+    filepath: str
+    title: Optional[str] = None
+    author: Optional[str] = None
+    reading_progress: Optional[float] = None
+
+    def __str__(self) -> str:
+        if self.reading_progress is None:
+            reading_progress_str = "N/A"
+        else:
+            reading_progress_str = f"{int(self.reading_progress * 100)}%"
+        reading_progress_str = reading_progress_str.rjust(4)
+
+        book_name: str
+        filename = self.filepath.replace(os.path.expanduser("~"), "~", 1)
+        if self.title is not None and self.author is not None:
+            book_name = f"{self.title} - {self.author} ({filename})"
+        elif self.title is None and self.author:
+            book_name = f"{filename} - {self.author}"
+        else:
+            book_name = filename
+
+        last_read_str = self.last_read.strftime("%I:%M%p %b %d")
+
+        return f"{reading_progress_str} {last_read_str}: {book_name}"
+
+
+@dataclass(frozen=True)
+class ReadingState:
+    """
+    Data model for reading state.
+
+    `row` has to be explicitly assigned with value
+    because Seamless feature needs it to adjust from
+    relative (to book's content index) row to absolute
+    (to book's entire content) row.
+
+    `rel_pctg` and `section` default to None and if
+    either of them is assigned with value, then it
+    will be overriding the `row` value.
+    """
+
+    content_index: int
+    textwidth: int
+    row: int
+    rel_pctg: Optional[float] = None
+    section: Optional[str] = None
+
+
+@dataclass(frozen=True)
+class SearchData:
+    direction: Direction = Direction.FORWARD
+    value: str = ""
+
+
+@dataclass(frozen=True)
+class LettersCount:
+    """
+    all: total letters in book
+    cumulative: list of total letters for previous contents
+                eg. let's say cumulative = (0, 50, 89, ...) it means
+                    0  is total cumulative letters of book contents[-1] to contents[0]
+                    50 is total cumulative letters of book contents[0] to contents[1]
+                    89 is total cumulative letters of book contents[0] to contents[2]
+    """
+
+    all: int
+    cumulative: Tuple[int, ...]
+
+
+@dataclass(frozen=True)
+class CharPos:
+    """
+    Describes character position in text.
+    eg. ["Lorem ipsum dolor sit amet,",  # row=0
+         "consectetur adipiscing elit."]  # row=1
+             ^CharPos(row=1, col=3)
+    """
+
+    row: int
+    col: int
+
+
+@dataclass(frozen=True)
+class TextMark:
+    """
+    Describes marking in text.
+    eg. Interval [CharPos(row=0, col=3), CharPos(row=1, col=4)]
+    notice the marking inclusive [] for both side instead of right exclusive [)
+    """
+
+    start: CharPos
+    end: Optional[CharPos] = None
+
+    def is_valid(self) -> bool:
+        """
+        Assert validity and check if the mark is unterminated
+        eg. <div><i>This is italic text</div>
+        Missing </i> tag
+        """
+        if self.end is not None:
+            if self.start.row == self.end.row:
+                return self.start.col <= self.end.col
+            else:
+                return self.start.row < self.end.row
+
+        return False
+
+
+@dataclass(frozen=True)
+class TextSpan:
+    """
+    Like TextMark but using span of letters (n_letters)
+    """
+
+    start: CharPos
+    n_letters: int
+
+
+@dataclass(frozen=True)
+class InlineStyle:
+    """
+    eg. InlineStyle(attr=curses.A_BOLD, row=3, cols=4, n_letters=3)
+    """
+
+    row: int
+    col: int
+    n_letters: int
+    attr: int
+
+
+@dataclass(frozen=True)
+class TocEntry:
+    label: str
+    content_index: int
+    section: Optional[str]
+
+
+@dataclass(frozen=True)
+class TextStructure:
+    """
+    Object that describes how the text
+    should be displayed in screen.
+
+    text_lines: ("list of lines", "of text", ...)
+    image_maps: {line_num: path/to/image/in/ebook/zip}
+    section_rows: {section_id: line_num}
+    formatting: (InlineStyle, ...)
+    """
+
+    text_lines: Tuple[str, ...]
+    image_maps: Mapping[int, str]
+    section_rows: Mapping[str, int]
+    formatting: Tuple[InlineStyle, ...]
+
+
+@dataclass(frozen=True)
+class NoUpdate:
+    pass
+
+
+class Key:
+    """
+    Because ord("k") chr(34) are confusing
+    """
+
+    def __init__(self, char_or_int: Union[str, int]):
+        self.value: int = char_or_int if isinstance(char_or_int, int) else ord(char_or_int)
+        self.char: str = char_or_int if isinstance(char_or_int, str) else chr(char_or_int)
+
+    def __eq__(self, other: Any) -> bool:
+        if isinstance(other, Key):
+            return self.value == other.value
+        return False
+
+    def __ne__(self, other: Any) -> bool:
+        return self.__eq__(other)
+
+    def __hash__(self) -> int:
+        return hash(self.value)
+
+
+class AppData:
+    @property
+    def prefix(self) -> Optional[str]:
+        """Return None if there exists no homedir | userdir"""
+        prefix: Optional[str] = None
+
+        # UNIX filesystem
+        homedir = os.getenv("HOME")
+        # WIN filesystem
+        userdir = os.getenv("USERPROFILE")
+
+        if homedir:
+            if os.path.isdir(os.path.join(homedir, ".config")):
+                prefix = os.path.join(homedir, ".config", "epy")
+            else:
+                prefix = os.path.join(homedir, ".epy")
+        elif userdir:
+            prefix = os.path.join(userdir, ".epy")
+
+        if prefix:
+            os.makedirs(prefix, exist_ok=True)
+
+        return prefix