add support for reading brotli and gzip files

2 files changed, 45 insertions, 5 deletions

diff --git a/src/gpx.rs b/src/gpx.rs
index 337a2a9..9dd7725 100644
--- a/src/gpx.rs
+++ b/src/gpx.rs
@@ -3,9 +3,16 @@
 //! We *could* use the [gpx](https://github.com/georust/gpx) crate, but we don't care about much
 //! other than the coordinates of the tracks. By implementing the little functionality ourselves,
 //! we can use a fast XML parser ([roxmltree](https://github.com/RazrFalcon/roxmltree)).
-use std::{f64::consts::PI, fs, path::Path};
+use std::{
+    f64::consts::PI,
+    ffi::OsStr,
+    fs::{self, File},
+    io::{BufReader, Read},
+    path::Path,
+};
 
 use color_eyre::eyre::{eyre, Result};
+use flate2::bufread::GzDecoder;
 use roxmltree::{Document, Node, NodeType};
 
 #[derive(Debug, Copy, Clone, PartialEq)]
@@ -67,12 +74,41 @@ pub fn extract_from_str(input: &str) -> Result<Vec<Coordinates>> {
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
 pub enum Compression {
     None,
+    Gzip,
+    Brotli,
+}
+
+impl Compression {
+    pub fn suggest_from_path<P: AsRef<Path>>(path: P) -> Option<Compression> {
+        let Some(ext) = path.as_ref().extension() else { return None };
+        if OsStr::new("br") == ext {
+            Some(Compression::Brotli)
+        } else if [OsStr::new("gz"), OsStr::new("gzip")].contains(&ext) {
+            Some(Compression::Gzip)
+        } else if OsStr::new("gpx") == ext {
+            Some(Compression::None)
+        } else {
+            None
+        }
+    }
 }
 
 pub fn extract_from_file<P: AsRef<Path>>(
     path: P,
-    _compression: Compression,
+    compression: Compression,
 ) -> Result<Vec<Coordinates>> {
-    let content = fs::read_to_string(path)?;
+    let content = match compression {
+        Compression::None => fs::read_to_string(path)?,
+        Compression::Gzip => {
+            let mut result = String::new();
+            GzDecoder::new(BufReader::new(File::open(path)?)).read_to_string(&mut result)?;
+            result
+        }
+        Compression::Brotli => {
+            let mut result = Vec::new();
+            brotli::BrotliDecompress(&mut BufReader::new(File::open(path)?), &mut result)?;
+            String::from_utf8(result)?
+        }
+    };
     extract_from_str(&content)
 }
diff --git a/src/main.rs b/src/main.rs
index f4a7aa7..e2dacb7 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -5,7 +5,7 @@ use std::{
 };
 
 use clap::Parser;
-use color_eyre::eyre::{bail, Context, Result};
+use color_eyre::eyre::{bail, eyre, Context, Result};
 use indicatif::{MultiProgress, ProgressBar, ProgressDrawTarget, ProgressStyle};
 use is_terminal::IsTerminal;
 use rayon::ThreadPoolBuilder;
@@ -14,6 +14,8 @@ mod gpx;
 mod layer;
 mod renderer;
 
+use gpx::Compression;
+
 #[derive(Parser, Debug, Clone)]
 #[command(author, version, about)]
 struct Args {
@@ -70,7 +72,9 @@ fn main() -> Result<()> {
 
     let mut tracks = Vec::new();
     for file in &args.files {
-        let data = gpx::extract_from_file(file, gpx::Compression::None).unwrap();
+        let compression = Compression::suggest_from_path(file)
+            .ok_or_else(|| eyre!("Could not determine format for {file:?}"))?;
+        let data = gpx::extract_from_file(file, compression)?;
         tracks.push(data);
         bar.inc(1);
     }