Merge pull request #74 from htkhiem/main

MPD v0.21+ filter syntax, DSD support & more

Author: kstep

src/output.rs

@@ -1,9 +1,7 @@
 //! The module describes output
 
-use crate::convert::FromMap;
+use crate::convert::FromIter;
 use crate::error::{Error, ProtoError};
-use std::collections::BTreeMap;
-use std::convert::From;
 
 /// Sound output
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
@@ -17,15 +15,51 @@ pub struct Output {
     pub name: String,
     /// enabled state
     pub enabled: bool,
+    /// Runtime-configurable, plugin-specific attributes, such as "dop" for ALSA
+    pub attributes: Vec<(String, String)>
 }
 
-impl FromMap for Output {
-    fn from_map(map: BTreeMap<String, String>) -> Result<Output, Error> {
-        Ok(Output {
-            id: get_field!(map, "outputid"),
-            plugin: get_field!(map, "plugin"),
-            name: map.get("outputname").map(|v| v.to_owned()).ok_or(Error::Proto(ProtoError::NoField("outputname")))?,
-            enabled: get_field!(map, bool "outputenabled"),
+impl FromIter for Output {
+    // Implement FromIter directly so that we can parse plugin-specific attributes
+    fn from_iter<I: Iterator<Item = Result<(String, String), Error>>>(iter: I) -> Result<Output, Error> {
+        let mut attributes = Vec::new();
+        let mut name: Option<String> = None;  // panic if unnamed
+        let mut plugin: Option<String> = None;  // panic if not found
+        let mut id: u32 = 0;
+        let mut enabled: bool = false;
+
+        for res in iter {
+            let line = res?;
+            match &*line.0 {
+                "outputid" => { id = line.1.parse::<u32>()? },
+                "outputname" => { name.replace(line.1); },
+                "plugin" => { plugin.replace(line.1); },
+                "outputenabled" => enabled = line.1 == "1",
+                "attribute" =>  {
+                    let terms: Vec<&str> = line.1.split("=").collect();
+                    if terms.len() != 2 {
+                        return Err(Error::Proto(ProtoError::NotPair));
+                    }
+                    attributes.push((terms[0].to_owned(), terms[1].to_owned()));
+                },
+                _ => {}
+            }
+        }
+
+        if name.is_none() {
+            return Err(Error::Proto(ProtoError::NoField("outputname")));
+        }
+
+        if plugin.is_none() {
+            return Err(Error::Proto(ProtoError::NoField("plugin")));
+        }
+
+        Ok(Self {
+            id,
+            plugin: plugin.unwrap(),
+            name: name.unwrap(),
+            enabled,
+            attributes
         })
     }
 }

src/search.rs

@@ -1,8 +1,11 @@
 #![allow(missing_docs)]
 // TODO: unfinished functionality
 
-use crate::proto::ToArguments;
-use std::borrow::Cow;
+use crate::proto::{Quoted, ToArguments};
+use std::{
+    io::Write,  // implements write for Vec
+    borrow::Cow
+};
 use std::convert::Into;
 use std::fmt;
 use std::result::Result as StdResult;
@@ -17,16 +20,39 @@ pub enum Term<'a> {
     Tag(Cow<'a, str>),
 }
 
+#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize), serde(untagged, rename_all = "lowercase"))]
+pub enum Operation {
+    Equals,
+    NotEquals,
+    Contains,
+    #[cfg_attr(feature = "serde", serde(rename = "starts_with"))]
+    StartsWith
+}
+
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub struct Filter<'a> {
     typ: Term<'a>,
     what: Cow<'a, str>,
+    how: Operation
 }
 
 impl<'a> Filter<'a> {
-    fn new<W>(typ: Term<'a>, what: W) -> Filter
+    pub fn new<W>(typ: Term<'a>, what: W) -> Filter
     where W: 'a + Into<Cow<'a, str>> {
-        Filter { typ, what: what.into() }
+        Filter {
+            typ,
+            what: what.into(),
+            how: Operation::Equals
+        }
+    }
+
+    pub fn new_with_op<W>(typ: Term<'a>, what: W, how: Operation) -> Filter
+    where W: 'a + Into<Cow<'a, str>> {
+        Filter {
+            typ,
+            what: what.into(),
+            how
+        }
     }
 }
 
@@ -59,6 +85,11 @@ impl<'a> Query<'a> {
         self.filters.push(Filter::new(term, value));
         self
     }
+
+    pub fn and_with_op<'b: 'a, V: 'b + Into<Cow<'b, str>>>(&mut self, term: Term<'b>, op: Operation, value: V) -> &mut Query<'a> {
+        self.filters.push(Filter::new_with_op(term, value, op));
+        self
+    }
 }
 
 impl<'a> fmt::Display for Term<'a> {
@@ -80,21 +111,70 @@ impl<'a> ToArguments for &'a Term<'a> {
     }
 }
 
+impl fmt::Display for Operation {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.write_str(match *self {
+            Operation::Equals => "==",
+            Operation::NotEquals => "!=",
+            Operation::Contains => "contains",
+            Operation::StartsWith => "starts_with"
+        })
+    }
+}
+
+impl ToArguments for Operation {
+    fn to_arguments<F, E>(&self, f: &mut F) -> StdResult<(), E>
+    where F: FnMut(&str) -> StdResult<(), E> {
+        f(&self.to_string())
+    }
+}
+
 impl<'a> ToArguments for &'a Filter<'a> {
     fn to_arguments<F, E>(&self, f: &mut F) -> StdResult<(), E>
     where F: FnMut(&str) -> StdResult<(), E> {
-        (&self.typ).to_arguments(f)?;
-        f(&self.what)
+        match self.typ {
+            // For some terms, the filter clause cannot have an operation
+            Term::Base | Term::LastMod => {
+                f(&format!(
+                    "({} {})",
+                    &self.typ,
+                    &Quoted(&self.what).to_string()
+                ))
+            }
+            _ => {
+                f(&format!(
+                    "({} {} {})",
+                    &self.typ,
+                    &self.how,
+                    &Quoted(&self.what).to_string())
+                )
+            }
+        }
     }
 }
 
 impl<'a> ToArguments for &'a Query<'a> {
+    // Use MPD 0.21+ filter syntax
     fn to_arguments<F, E>(&self, f: &mut F) -> StdResult<(), E>
     where F: FnMut(&str) -> StdResult<(), E> {
-        for filter in &self.filters {
-            filter.to_arguments(f)?
+        // Construct the query string in its entirety first before escaping
+        if !self.filters.is_empty() {
+            let mut qs = String::new();
+            for (i, filter) in self.filters.iter().enumerate() {
+                if i > 0 {
+                    qs.push_str(" AND ");
+                }
+                // Leave escaping to the filter since terms should not be escaped or quoted
+                filter.to_arguments(&mut |arg| {
+                    qs.push_str(arg);
+                    Ok(())
+                })?;
+            }
+            // println!("Singly escaped query string: {}", &qs);
+            f(&qs)
+        } else {
+            Ok(())
         }
-        Ok(())
     }
 }
 

src/status.rs

@@ -102,8 +102,8 @@ impl FromIter for Status {
                 "duration" => result.duration = line.1.parse::<f32>().ok().map(|v| Duration::from_millis((v * 1000.0) as u64)),
                 "bitrate" => result.bitrate = Some(line.1.parse()?),
                 "xfade" => result.crossfade = Some(Duration::from_secs(line.1.parse()?)),
-                // "mixrampdb" => 0.0, //get_field!(map, "mixrampdb"),
-                // "mixrampdelay" => None, //get_field!(map, opt "mixrampdelay").map(|v: f64| Duration::milliseconds((v * 1000.0) as i64)),
+                "mixrampdb" => result.mixrampdb = line.1.parse::<f32>()?,
+                "mixrampdelay" => result.mixrampdelay = Some(Duration::from_secs_f64(line.1.parse()?)),
                 "audio" => result.audio = Some(line.1.parse()?),
                 "updating_db" => result.updating_db = Some(line.1.parse()?),
                 "error" => result.error = Some(line.1.to_owned()),
@@ -120,17 +120,33 @@ impl FromIter for Status {
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[derive(Debug, Copy, Clone, PartialEq)]
 pub struct AudioFormat {
-    /// sample rate, kbps
+    /// Sample rate, kbps.
+    /// For DSD, to align with MPD's internal handling, the returned rate will be in kilobytes per second instead.
+    /// See https://mpd.readthedocs.io/en/latest/user.html#audio-output-format.
     pub rate: u32,
-    /// sample resolution in bits, can be 0 for floating point resolution
+    /// Sample resolution in bits, can be 0 for floating point resolution or 1 for DSD.
     pub bits: u8,
-    /// number of channels
+    /// Number of channels.
     pub chans: u8,
 }
 
 impl FromStr for AudioFormat {
     type Err = ParseError;
     fn from_str(s: &str) -> Result<AudioFormat, ParseError> {
+        if s.contains("dsd") {
+            // DSD format string only contains two terms: "dsd..." and number of channels.
+            // To shoehorn into our current AudioFormat struct, use the following conversion:
+            // - Sample rate: 44100 * the DSD multiplier / 8. For example, DSD64 is sampled at 2.8224MHz.
+            // - Bits: 1 (DSD is a sequence of single-bit values, or PDM).
+            // - Channels: as usual.
+            let mut it = s.split(':');
+            let dsd_mul: u32 = it.next().ok_or(ParseError::NoRate).and_then(|v| v[3..].parse().map_err(ParseError::BadRate))?;
+            return Ok(AudioFormat {
+                rate: dsd_mul * 44100 / 8,
+                bits: 1,
+                chans: it.next().ok_or(ParseError::NoChans).and_then(|v| v.parse().map_err(ParseError::BadChans))?,
+            });
+        }
         let mut it = s.split(':');
         Ok(AudioFormat {
             rate: it.next().ok_or(ParseError::NoRate).and_then(|v| v.parse().map_err(ParseError::BadRate))?,