1 files changed, 96 insertions, 0 deletions
diff --git a/src-tauri/src/core/modpack/extractor.rs b/src-tauri/src/core/modpack/extractor.rs
new file mode 100644
index 0000000..b8d4ff2
--- /dev/null
+++ b/src-tauri/src/core/modpack/extractor.rs
@@ -0,0 +1,96 @@
+use std::{fs, path::Path};
+
+use super::archive;
+
+pub(crate) trait ProgressReporter {
+    fn report(&mut self, current: usize, total: usize, name: &str);
+}
+
+impl<F> ProgressReporter for F
+where
+    F: FnMut(usize, usize, &str),
+{
+    fn report(&mut self, current: usize, total: usize, name: &str) {
+        self(current, total, name);
+    }
+}
+
+pub(crate) trait OverrideExtractor: Send + Sync {
+    fn extract(
+        &self,
+        path: &Path,
+        game_dir: &Path,
+        override_prefixes: &[String],
+        reporter: &mut dyn ProgressReporter,
+    ) -> Result<(), String>;
+}
+
+#[derive(Debug, Default, Clone, Copy)]
+pub(crate) struct ZipOverrideExtractor;
+
+impl ZipOverrideExtractor {
+    pub(crate) fn new() -> Self {
+        Self
+    }
+}
+
+impl OverrideExtractor for ZipOverrideExtractor {
+    fn extract(
+        &self,
+        path: &Path,
+        game_dir: &Path,
+        override_prefixes: &[String],
+        reporter: &mut dyn ProgressReporter,
+    ) -> Result<(), String> {
+        let mut archive = archive::open(path)?;
+        let all_names = archive::list_names(&mut archive);
+        let prefixes: Vec<&str> = override_prefixes
+            .iter()
+            .filter(|prefix| {
+                all_names
+                    .iter()
+                    .any(|name| name.starts_with(prefix.as_str()))
+            })
+            .map(String::as_str)
+            .collect();
+        let strip = |name: &str| -> Option<String> {
+            prefixes.iter().find_map(|prefix| {
+                let relative = name.strip_prefix(*prefix)?;
+                (!relative.is_empty()).then(|| relative.to_string())
+            })
+        };
+        let total = all_names
+            .iter()
+            .filter(|name| strip(name).is_some())
+            .count();
+        let mut current = 0;
+
+        for index in 0..archive.len() {
+            let mut entry = archive.by_index(index).map_err(|e| e.to_string())?;
+            let name = entry.name().to_string();
+            let Some(relative) = strip(&name) else {
+                continue;
+            };
+
+            let outpath = game_dir.join(&relative);
+            if !outpath.starts_with(game_dir) {
+                continue;
+            }
+
+            if entry.is_dir() {
+                fs::create_dir_all(&outpath).map_err(|e| e.to_string())?;
+            } else {
+                if let Some(parent) = outpath.parent() {
+                    fs::create_dir_all(parent).map_err(|e| e.to_string())?;
+                }
+                let mut file = fs::File::create(&outpath).map_err(|e| e.to_string())?;
+                std::io::copy(&mut entry, &mut file).map_err(|e| e.to_string())?;
+            }
+
+            current += 1;
+            reporter.report(current, total, &relative);
+        }
+
+        Ok(())
+    }
+}