metal: implement VRR

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

@@ -0,0 +1,116 @@
+use {
+    crate::{
+        config::{
+            context::Context,
+            extractor::{opt, val, Extractor, ExtractorError},
+            parser::{DataType, ParseResult, Parser, UnexpectedDataType},
+            Vrr,
+        },
+        toml::{
+            toml_span::{Span, Spanned, SpannedExt},
+            toml_value::Value,
+        },
+    },
+    indexmap::IndexMap,
+    jay_config::video::VrrMode,
+    thiserror::Error,
+};
+
+#[derive(Debug, Error)]
+pub enum VrrParserError {
+    #[error(transparent)]
+    Expected(#[from] UnexpectedDataType),
+    #[error(transparent)]
+    Extract(#[from] ExtractorError),
+}
+
+pub struct VrrParser<'a>(pub &'a Context<'a>);
+
+impl Parser for VrrParser<'_> {
+    type Value = Vrr;
+    type Error = VrrParserError;
+    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, cursor_hz) = ext.extract((opt(val("mode")), opt(val("cursor-hz"))))?;
+        let mode = mode.and_then(|m| match m.parse(&mut VrrModeParser) {
+            Ok(m) => Some(m),
+            Err(e) => {
+                log::error!("Could not parse mode: {}", self.0.error(e));
+                None
+            }
+        });
+        let cursor_hz = cursor_hz.and_then(|m| match m.parse(&mut VrrRateParser) {
+            Ok(m) => Some(m),
+            Err(e) => {
+                log::error!("Could not parse rate: {}", self.0.error(e));
+                None
+            }
+        });
+        Ok(Vrr { mode, cursor_hz })
+    }
+}
+
+#[derive(Debug, Error)]
+pub enum VrrModeParserError {
+    #[error(transparent)]
+    Expected(#[from] UnexpectedDataType),
+    #[error("Unknown mode {0}")]
+    UnknownMode(String),
+}
+
+struct VrrModeParser;
+
+impl Parser for VrrModeParser {
+    type Value = VrrMode;
+    type Error = VrrModeParserError;
+    const EXPECTED: &'static [DataType] = &[DataType::String];
+
+    fn parse_string(&mut self, span: Span, string: &str) -> ParseResult<Self> {
+        let mode = match string {
+            "never" => VrrMode::NEVER,
+            "always" => VrrMode::ALWAYS,
+            "variant1" => VrrMode::VARIANT_1,
+            "variant2" => VrrMode::VARIANT_2,
+            "variant3" => VrrMode::VARIANT_3,
+            _ => return Err(VrrModeParserError::UnknownMode(string.to_string()).spanned(span)),
+        };
+        Ok(mode)
+    }
+}
+
+#[derive(Debug, Error)]
+pub enum VrrRateParserError {
+    #[error(transparent)]
+    Expected(#[from] UnexpectedDataType),
+    #[error("Unknown rate {0}")]
+    UnknownString(String),
+}
+
+struct VrrRateParser;
+
+impl Parser for VrrRateParser {
+    type Value = f64;
+    type Error = VrrRateParserError;
+    const EXPECTED: &'static [DataType] = &[DataType::String, DataType::Float, DataType::Integer];
+
+    fn parse_string(&mut self, span: Span, string: &str) -> ParseResult<Self> {
+        match string {
+            "none" => Ok(f64::INFINITY),
+            _ => Err(VrrRateParserError::UnknownString(string.to_string()).spanned(span)),
+        }
+    }
+
+    fn parse_integer(&mut self, _span: Span, integer: i64) -> ParseResult<Self> {
+        Ok(integer as _)
+    }
+
+    fn parse_float(&mut self, _span: Span, float: f64) -> ParseResult<Self> {
+        Ok(float)
+    }
+}