pile-audio refactor

crates/pile-audio/src/blocks/padding.rs

@@ -0,0 +1,53 @@
+use std::{fmt::Debug, io::Read};
+
+use super::{FlacMetablockDecode, FlacMetablockEncode, FlacMetablockHeader, FlacMetablockType};
+use crate::{FlacDecodeError, FlacEncodeError};
+
+/// A padding block in a FLAC file.
+#[derive(Debug)]
+pub struct FlacPaddingBlock {
+	/// The length of this padding, in bytes.
+	pub size: u32,
+}
+
+impl FlacMetablockDecode for FlacPaddingBlock {
+	#[expect(clippy::expect_used)]
+	fn decode(data: &[u8]) -> Result<Self, FlacDecodeError> {
+		if data.iter().any(|x| *x != 0u8) {
+			return Err(FlacDecodeError::MalformedBlock);
+		}
+
+		Ok(Self {
+			size: data
+				.len()
+				.try_into()
+				.expect("padding size does not fit into u32"),
+		})
+	}
+}
+
+impl FlacMetablockEncode for FlacPaddingBlock {
+	fn get_len(&self) -> u32 {
+		self.size
+	}
+
+	fn encode(
+		&self,
+		is_last: bool,
+		with_header: bool,
+		target: &mut impl std::io::Write,
+	) -> Result<(), FlacEncodeError> {
+		if with_header {
+			let header = FlacMetablockHeader {
+				block_type: FlacMetablockType::Padding,
+				length: self.get_len(),
+				is_last,
+			};
+			header.encode(target)?;
+		}
+
+		std::io::copy(&mut std::io::repeat(0u8).take(self.size.into()), target)?;
+
+		return Ok(());
+	}
+}