Add mediafile import from memory

[codecrafter404]

Problem

The package creation currently only allows for media files to be read from the filesystem.

Solution

The package now exposes a function to create mediafiles from memory: new_from_memory.
To allow imports both from the filesystem and from memory, a new enum was introduced: MediaFile.

Example usage

use genanki_rs::{Package, Deck, Note, Model, Field, Template, MediaFile};

const VALID_MP3: &[u8] =
    b"\xff\xe3\x18\xc4\x00\x00\x00\x03H\x00\x00\x00\x00LAME3.98.2\x00\x00\x00\
    \x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\
    \x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\
    \x00\x00\x00\x00\x00\x00\x00\x00\x00\x00";
const VALID_JPG: &[u8] =
    b"\xff\xd8\xff\xdb\x00C\x00\x03\x02\x02\x02\x02\x02\x03\x02\x02\x02\x03\x03\
    \x03\x03\x04\x06\x04\x04\x04\x04\x04\x08\x06\x06\x05\x06\t\x08\n\n\t\x08\t\
    \t\n\x0c\x0f\x0c\n\x0b\x0e\x0b\t\t\r\x11\r\x0e\x0f\x10\x10\x11\x10\n\x0c\
    \x12\x13\x12\x10\x13\x0f\x10\x10\x10\xff\xc9\x00\x0b\x08\x00\x01\x00\x01\
    \x01\x01\x11\x00\xff\xcc\x00\x06\x00\x10\x10\x05\xff\xda\x00\x08\x01\x01\
    \x00\x00?\x00\xd2\xcf \xff\xd9";

let model = Model::new(
    1607392319,
    "Simple Model",
    vec![
        Field::new("Question"),
        Field::new("Answer"),
        Field::new("MyMedia"),
    ],
    vec![Template::new("Card 1")
        .qfmt("{{Question}}{{Question}}<br>{{MyMedia}}")
        .afmt(r#"{{FrontSide}}<hr id="answer">{{Answer}}"#)],
);

let mut deck = Deck::new(1234, "Example Deck", "Example Deck with media");
deck.add_note(Note::new(model.clone(), vec!["What is the capital of France?", "Paris", "[sound:sound.mp3]"])?);
deck.add_note(Note::new(model.clone(), vec!["What is the capital of France?", "Paris", r#"<img src="image.jpg">"#])?);

let mut package = Package::new_from_memory(vec![deck], vec![MediaFile::new_from_bytes(VALID_MP3, "sound.mp3"), MediaFile::new_from_bytes(VALID_JPG, "image.jpg")])?;
package.write_to_file("output.apkg")?;

Tests

Although I was unable to successfully run all tests locally, I have implemented a test for importing media files from memory that should pass.

[jacksonriley]

This clone is probably not required?

[jacksonriley]

Would it be possible not to call to_vec here and just keep a reference to the bytes? Could potentially avoid a chunky memcopy