mpvipc-async/src/property_parser.rs

343 lines
12 KiB
Rust

//! JSON parsing logic for properties returned by
//! [[`Event::PropertyChange`], and used internally in `MpvExt`
//! to parse the response from `Mpv::get_property()`.
//!
//! This module is used to parse the json data from the `data` field of
//! known properties. Mpv has about 1000 different properties
//! as of `v0.38.0`, so this module will only implement the most common ones.
// TODO: reuse this logic for providing a more typesafe response API to `Mpv::get_property()`
// Although this data is currently of type `Option<`
use std::collections::HashMap;
use serde::{Deserialize, Serialize};
use crate::{MpvDataType, MpvError, PlaylistEntry};
/// An incomplete list of properties that mpv can return.
///
/// Unimplemented properties will be returned with it's data
/// as a `Property::Unknown` variant.
///
/// See <https://mpv.io/manual/master/#properties> for
/// the upstream list of properties.
#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
#[serde(rename_all = "kebab-case")]
pub enum Property {
Path(Option<String>),
Pause(bool),
PlaybackTime(Option<f64>),
Duration(Option<f64>),
Metadata(Option<HashMap<String, MpvDataType>>),
Playlist(Vec<PlaylistEntry>),
PlaylistPos(Option<usize>),
LoopFile(LoopProperty),
LoopPlaylist(LoopProperty),
TimePos(f64),
TimeRemaining(f64),
Speed(f64),
Volume(f64),
Mute(bool),
Unknown {
name: String,
data: Option<MpvDataType>,
},
}
#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
#[serde(rename_all = "kebab-case")]
pub enum LoopProperty {
N(usize),
Inf,
No,
}
/// Parse a highlevel [`Property`] object from mpv data.
///
/// This is intended to be used with the `data` field of
/// `Event::PropertyChange` and the response from `Mpv::get_property_value()`.
pub fn parse_property(name: &str, data: Option<MpvDataType>) -> Result<Property, MpvError> {
match name {
"path" => {
let path = match data {
Some(MpvDataType::String(s)) => Some(s),
Some(MpvDataType::Null) => None,
Some(data) => {
return Err(MpvError::DataContainsUnexpectedType {
expected_type: "String".to_owned(),
received: data,
})
}
None => {
return Err(MpvError::MissingMpvData);
}
};
Ok(Property::Path(path))
}
"pause" => {
let pause = match data {
Some(MpvDataType::Bool(b)) => b,
Some(data) => {
return Err(MpvError::DataContainsUnexpectedType {
expected_type: "bool".to_owned(),
received: data,
})
}
None => {
return Err(MpvError::MissingMpvData);
}
};
Ok(Property::Pause(pause))
}
"playback-time" => {
let playback_time = match data {
Some(MpvDataType::Double(d)) => Some(d),
None | Some(MpvDataType::Null) => None,
Some(data) => {
return Err(MpvError::DataContainsUnexpectedType {
expected_type: "f64".to_owned(),
received: data,
})
}
};
Ok(Property::PlaybackTime(playback_time))
}
"duration" => {
let duration = match data {
Some(MpvDataType::Double(d)) => Some(d),
None | Some(MpvDataType::Null) => None,
Some(data) => {
return Err(MpvError::DataContainsUnexpectedType {
expected_type: "f64".to_owned(),
received: data,
})
}
};
Ok(Property::Duration(duration))
}
"metadata" => {
let metadata = match data {
Some(MpvDataType::HashMap(m)) => Some(m),
None | Some(MpvDataType::Null) => None,
Some(data) => {
return Err(MpvError::DataContainsUnexpectedType {
expected_type: "HashMap".to_owned(),
received: data,
})
}
};
Ok(Property::Metadata(metadata))
}
"playlist" => {
let playlist = match data {
Some(MpvDataType::Array(a)) => mpv_array_to_playlist(&a)?,
None => Vec::new(),
Some(data) => {
return Err(MpvError::DataContainsUnexpectedType {
expected_type: "Array".to_owned(),
received: data,
})
}
};
Ok(Property::Playlist(playlist))
}
"playlist-pos" => {
let playlist_pos = match data {
Some(MpvDataType::Usize(u)) => Some(u),
Some(MpvDataType::MinusOne) => None,
Some(MpvDataType::Null) => None,
None => None,
Some(data) => {
return Err(MpvError::DataContainsUnexpectedType {
expected_type: "usize or -1".to_owned(),
received: data,
})
}
};
Ok(Property::PlaylistPos(playlist_pos))
}
"loop-file" => {
let loop_file = match data.to_owned() {
Some(MpvDataType::Usize(n)) => Some(LoopProperty::N(n)),
Some(MpvDataType::Bool(b)) => match b {
true => Some(LoopProperty::Inf),
false => Some(LoopProperty::No),
},
Some(MpvDataType::String(s)) => match s.as_str() {
"inf" => Some(LoopProperty::Inf),
_ => None,
},
_ => None,
}
.ok_or(match data {
Some(data) => MpvError::DataContainsUnexpectedType {
expected_type: "'inf', bool, or usize".to_owned(),
received: data,
},
None => MpvError::MissingMpvData,
})?;
Ok(Property::LoopFile(loop_file))
}
"loop-playlist" => {
let loop_playlist = match data.to_owned() {
Some(MpvDataType::Usize(n)) => Some(LoopProperty::N(n)),
Some(MpvDataType::Bool(b)) => match b {
true => Some(LoopProperty::Inf),
false => Some(LoopProperty::No),
},
Some(MpvDataType::String(s)) => match s.as_str() {
"inf" => Some(LoopProperty::Inf),
_ => None,
},
_ => None,
}
.ok_or(match data {
Some(data) => MpvError::DataContainsUnexpectedType {
expected_type: "'inf', bool, or usize".to_owned(),
received: data,
},
None => MpvError::MissingMpvData,
})?;
Ok(Property::LoopPlaylist(loop_playlist))
}
"time-pos" => {
let time_pos = match data {
Some(MpvDataType::Double(d)) => d,
Some(data) => {
return Err(MpvError::DataContainsUnexpectedType {
expected_type: "f64".to_owned(),
received: data,
})
}
None => {
return Err(MpvError::MissingMpvData);
}
};
Ok(Property::TimePos(time_pos))
}
"time-remaining" => {
let time_remaining = match data {
Some(MpvDataType::Double(d)) => d,
Some(data) => {
return Err(MpvError::DataContainsUnexpectedType {
expected_type: "f64".to_owned(),
received: data,
})
}
None => {
return Err(MpvError::MissingMpvData);
}
};
Ok(Property::TimeRemaining(time_remaining))
}
"speed" => {
let speed = match data {
Some(MpvDataType::Double(d)) => d,
Some(data) => {
return Err(MpvError::DataContainsUnexpectedType {
expected_type: "f64".to_owned(),
received: data,
})
}
None => {
return Err(MpvError::MissingMpvData);
}
};
Ok(Property::Speed(speed))
}
"volume" => {
let volume = match data {
Some(MpvDataType::Double(d)) => d,
Some(data) => {
return Err(MpvError::DataContainsUnexpectedType {
expected_type: "f64".to_owned(),
received: data,
})
}
None => {
return Err(MpvError::MissingMpvData);
}
};
Ok(Property::Volume(volume))
}
"mute" => {
let mute = match data {
Some(MpvDataType::Bool(b)) => b,
Some(data) => {
return Err(MpvError::DataContainsUnexpectedType {
expected_type: "bool".to_owned(),
received: data,
})
}
None => {
return Err(MpvError::MissingMpvData);
}
};
Ok(Property::Mute(mute))
}
// TODO: add missing cases
_ => Ok(Property::Unknown {
name: name.to_owned(),
data,
}),
}
}
fn mpv_data_to_playlist_entry(
map: &HashMap<String, MpvDataType>,
) -> Result<PlaylistEntry, MpvError> {
let filename = match map.get("filename") {
Some(MpvDataType::String(s)) => s.to_string(),
Some(data) => {
return Err(MpvError::DataContainsUnexpectedType {
expected_type: "String".to_owned(),
received: data.clone(),
})
}
None => return Err(MpvError::MissingMpvData),
};
let title = match map.get("title") {
Some(MpvDataType::String(s)) => s.to_string(),
Some(data) => {
return Err(MpvError::DataContainsUnexpectedType {
expected_type: "String".to_owned(),
received: data.clone(),
})
}
None => return Err(MpvError::MissingMpvData),
};
let current = match map.get("current") {
Some(MpvDataType::Bool(b)) => *b,
Some(data) => {
return Err(MpvError::DataContainsUnexpectedType {
expected_type: "bool".to_owned(),
received: data.clone(),
})
}
None => return Err(MpvError::MissingMpvData),
};
Ok(PlaylistEntry {
id: 0,
filename,
title,
current,
})
}
fn mpv_array_to_playlist(array: &[MpvDataType]) -> Result<Vec<PlaylistEntry>, MpvError> {
array
.iter()
.map(|value| match value {
MpvDataType::HashMap(map) => mpv_data_to_playlist_entry(map),
_ => Err(MpvError::DataContainsUnexpectedType {
expected_type: "HashMap".to_owned(),
received: value.clone(),
}),
})
.enumerate()
.map(|(id, entry)| entry.map(|entry| PlaylistEntry { id, ..entry }))
.collect()
}