lofty 0.25.4

use crate::config::WriteOptions;
use crate::id3::v2::error::FrameParseError;
use crate::id3::v2::frame::content::verify_encoding;
use crate::id3::v2::frame::error::FrameEncodingError;
use crate::id3::v2::header::Id3v2Version;
use crate::id3::v2::{FrameFlags, FrameHeader, FrameId};
use crate::util::text::{TextDecodeOptions, TextEncoding, decode_text};

use std::borrow::Cow;
use std::io::Read;

use byteorder::ReadBytesExt;

/// An `ID3v2` key-value frame
#[derive(Clone, Debug, Eq, PartialEq, Hash)]
pub struct KeyValueFrame<'a> {
	pub(crate) header: FrameHeader<'a>,
	/// The encoding of the text
	pub encoding: TextEncoding,
	/// The key value pairs. Keys can be specified multiple times
	pub key_value_pairs: Cow<'a, [(Cow<'a, str>, Cow<'a, str>)]>,
}

impl<'a> KeyValueFrame<'a> {
	/// Create a new [`KeyValueFrame`]
	pub fn new(
		id: FrameId<'a>,
		encoding: TextEncoding,
		key_value_pairs: impl Into<Cow<'a, [(Cow<'a, str>, Cow<'a, str>)]>>,
	) -> Self {
		let header = FrameHeader::new(id, FrameFlags::default());
		Self {
			header,
			encoding,
			key_value_pairs: key_value_pairs.into(),
		}
	}

	/// Get the ID for the frame
	pub fn id(&self) -> &FrameId<'_> {
		&self.header.id
	}

	/// Get the flags for the frame
	pub fn flags(&self) -> FrameFlags {
		self.header.flags
	}

	/// Set the flags for the frame
	pub fn set_flags(&mut self, flags: FrameFlags) {
		self.header.flags = flags;
	}

	/// Read an [`KeyValueFrame`] from a slice
	///
	/// NOTE: This expects the frame header to have already been skipped
	///
	/// # Errors
	///
	/// * Unable to decode the text
	///
	/// ID3v2.2:
	///
	/// * The encoding is not [`TextEncoding::Latin1`] or [`TextEncoding::UTF16`]
	pub fn parse<R>(
		reader: &mut R,
		id: FrameId<'a>,
		frame_flags: FrameFlags,
		version: Id3v2Version,
	) -> Result<Option<Self>, FrameParseError>
	where
		R: Read,
	{
		let encoding_byte = match reader.read_u8() {
			Ok(byte) => byte,
			Err(e) => return Err(FrameParseError::new(Some(id.into_owned()), Box::new(e))),
		};

		let encoding = match verify_encoding(encoding_byte, version) {
			Ok(encoding) => encoding,
			Err(e) => return Err(FrameParseError::new(Some(id.into_owned()), Box::new(e))),
		};

		let mut values = Vec::new();

		let mut text_decode_options = TextDecodeOptions::new().encoding(encoding).terminated(true);

		// We have to read the first key/value pair separately because it may be the only string with a BOM

		let first_key = match decode_text(reader, text_decode_options) {
			Ok(key) => key,
			Err(e) => return Err(FrameParseError::new(Some(id.into_owned()), Box::new(e))),
		};

		if first_key.bytes_read == 0 {
			return Ok(None);
		}

		if encoding == TextEncoding::UTF16 {
			text_decode_options = text_decode_options.bom(first_key.bom);
		}

		let first_value = match decode_text(reader, text_decode_options) {
			Ok(key) => key,
			Err(e) => return Err(FrameParseError::new(Some(id.into_owned()), Box::new(e))),
		};

		values.push((
			Cow::Owned(first_key.content),
			Cow::Owned(first_value.content),
		));

		loop {
			let key = match decode_text(reader, text_decode_options) {
				Ok(key) => key,
				Err(e) => return Err(FrameParseError::new(Some(id.into_owned()), Box::new(e))),
			};
			let value = match decode_text(reader, text_decode_options) {
				Ok(key) => key,
				Err(e) => return Err(FrameParseError::new(Some(id.into_owned()), Box::new(e))),
			};
			if key.bytes_read == 0 || value.bytes_read == 0 {
				break;
			}

			values.push((Cow::Owned(key.content), Cow::Owned(value.content)));
		}

		let header = FrameHeader::new(id, frame_flags);
		Ok(Some(Self {
			header,
			encoding,
			key_value_pairs: Cow::Owned(values),
		}))
	}

	/// Convert a [`KeyValueFrame`] to a byte vec
	///
	/// # Errors
	///
	/// * [`WriteOptions::lossy_text_encoding()`] is disabled and the content cannot be encoded in the specified [`TextEncoding`].
	pub fn as_bytes(&self, write_options: WriteOptions) -> Result<Vec<u8>, FrameEncodingError> {
		let mut encoding = self.encoding;
		if write_options.use_id3v23 {
			encoding = encoding.to_id3v23();
		}

		let mut content = vec![encoding as u8];

		for (key, value) in &*self.key_value_pairs {
			content.append(&mut encoding.encode(key, true, write_options.lossy_text_encoding)?);
			content.append(&mut encoding.encode(value, true, write_options.lossy_text_encoding)?);
		}
		Ok(content)
	}
}

impl KeyValueFrame<'_> {
	pub(crate) fn borrow(&self) -> KeyValueFrame<'_> {
		KeyValueFrame {
			header: self.header.borrow(),
			encoding: self.encoding,
			key_value_pairs: Cow::Borrowed(&self.key_value_pairs),
		}
	}
}

#[cfg(test)]
mod tests {
	use crate::config::WriteOptions;
	use crate::id3::v2::{FrameFlags, FrameHeader, FrameId, Id3v2Version, KeyValueFrame};
	use crate::util::text::TextEncoding;

	use std::borrow::Cow;

	const FRAME_ID: FrameId<'static> = FrameId::Valid(Cow::Borrowed("TIPL"));

	fn expected(encoding: TextEncoding) -> KeyValueFrame<'static> {
		KeyValueFrame {
			header: FrameHeader::new(FRAME_ID, FrameFlags::default()),
			encoding,
			key_value_pairs: Cow::Owned(vec![
				("producer".into(), "Serial-ATA".into()),
				("mixer".into(), "lofty-rs".into()),
			]),
		}
	}

	#[test_log::test]
	fn tipl_decode() {
		let cont = crate::tag::utils::test_utils::read_path("tests/tags/assets/id3v2/test.tipl");

		let parsed_tipl = KeyValueFrame::parse(
			&mut &cont[..],
			FRAME_ID,
			FrameFlags::default(),
			Id3v2Version::V4,
		)
		.unwrap()
		.unwrap();

		assert_eq!(parsed_tipl, expected(TextEncoding::Latin1));
	}

	#[test_log::test]
	fn tipl_encode() {
		let encoded = expected(TextEncoding::Latin1)
			.as_bytes(WriteOptions::default())
			.unwrap();

		let expected_bytes =
			crate::tag::utils::test_utils::read_path("tests/tags/assets/id3v2/test.tipl");

		assert_eq!(encoded, expected_bytes);
	}

	#[test_log::test]
	fn tipl_decode_utf16() {
		let cont =
			crate::tag::utils::test_utils::read_path("tests/tags/assets/id3v2/test_utf16.tipl");

		let parsed_tipl = KeyValueFrame::parse(
			&mut &cont[..],
			FRAME_ID,
			FrameFlags::default(),
			Id3v2Version::V4,
		)
		.unwrap()
		.unwrap();

		assert_eq!(parsed_tipl, expected(TextEncoding::UTF16));
	}

	#[test_log::test]
	fn tipl_encode_utf_16() {
		let encoded = expected(TextEncoding::UTF16)
			.as_bytes(WriteOptions::default())
			.unwrap();

		let expected_bytes =
			crate::tag::utils::test_utils::read_path("tests/tags/assets/id3v2/test_utf16.tipl");

		assert_eq!(encoded, expected_bytes);
	}
}