metal: implement tearing

toml-config/src/config/parsers/tearing.rs

@@ -0,0 +1,78 @@
+use {
+    crate::{
+        config::{
+            context::Context,
+            extractor::{opt, val, Extractor, ExtractorError},
+            parser::{DataType, ParseResult, Parser, UnexpectedDataType},
+            Tearing,
+        },
+        toml::{
+            toml_span::{Span, Spanned, SpannedExt},
+            toml_value::Value,
+        },
+    },
+    indexmap::IndexMap,
+    jay_config::video::TearingMode,
+    thiserror::Error,
+};
+
+#[derive(Debug, Error)]
+pub enum TearingParserError {
+    #[error(transparent)]
+    Expected(#[from] UnexpectedDataType),
+    #[error(transparent)]
+    Extract(#[from] ExtractorError),
+}
+
+pub struct TearingParser<'a>(pub &'a Context<'a>);
+
+impl Parser for TearingParser<'_> {
+    type Value = Tearing;
+    type Error = TearingParserError;
+    const EXPECTED: &'static [DataType] = &[DataType::Table];
+
+    fn parse_table(
+        &mut self,
+        span: Span,
+        table: &IndexMap<Spanned<String>, Spanned<Value>>,
+    ) -> ParseResult<Self> {
+        let mut ext = Extractor::new(self.0, span, table);
+        let mode = ext.extract(opt(val("mode")))?;
+        let mode = mode.and_then(|m| match m.parse(&mut TearingModeParser) {
+            Ok(m) => Some(m),
+            Err(e) => {
+                log::error!("Could not parse mode: {}", self.0.error(e));
+                None
+            }
+        });
+        Ok(Tearing { mode })
+    }
+}
+
+#[derive(Debug, Error)]
+pub enum TearingModeParserError {
+    #[error(transparent)]
+    Expected(#[from] UnexpectedDataType),
+    #[error("Unknown mode {0}")]
+    UnknownMode(String),
+}
+
+struct TearingModeParser;
+
+impl Parser for TearingModeParser {
+    type Value = TearingMode;
+    type Error = TearingModeParserError;
+    const EXPECTED: &'static [DataType] = &[DataType::String];
+
+    fn parse_string(&mut self, span: Span, string: &str) -> ParseResult<Self> {
+        let mode = match string {
+            "never" => TearingMode::NEVER,
+            "always" => TearingMode::ALWAYS,
+            "variant1" => TearingMode::VARIANT_1,
+            "variant2" => TearingMode::VARIANT_2,
+            "variant3" => TearingMode::VARIANT_3,
+            _ => return Err(TearingModeParserError::UnknownMode(string.to_string()).spanned(span)),
+        };
+        Ok(mode)
+    }
+}