1 files changed, 109 insertions, 0 deletions
diff --git a/crates/shirabe/src/util/zip.rs b/crates/shirabe/src/util/zip.rs
index 583d397..296345a 100644
--- a/crates/shirabe/src/util/zip.rs
+++ b/crates/shirabe/src/util/zip.rs
@@ -1 +1,110 @@
 //! ref: composer/src/Composer/Util/Zip.php
+
+use anyhow::Result;
+use indexmap::IndexMap;
+use shirabe_php_shim::{dirname, extension_loaded, implode, stream_get_contents, RuntimeException, ZipArchive};
+
+pub struct Zip;
+
+impl Zip {
+    pub fn get_composer_json(path_to_zip: &str) -> Result<Option<String>> {
+        if !extension_loaded("zip") {
+            return Err(RuntimeException {
+                message: "The Zip Util requires PHP's zip extension".to_string(),
+                code: 0,
+            }
+            .into());
+        }
+
+        let mut zip = ZipArchive::new();
+        if !zip.open(path_to_zip) {
+            return Ok(None);
+        }
+
+        if zip.num_files == 0 {
+            zip.close();
+            return Ok(None);
+        }
+
+        let found_file_index = Self::locate_file(&zip, "composer.json")?;
+
+        let mut content: Option<String> = None;
+        let configuration_file_name = zip.get_name_index(found_file_index);
+        let stream = zip.get_stream(&configuration_file_name);
+
+        if stream.is_some() {
+            content = stream_get_contents(stream.unwrap());
+        }
+
+        zip.close();
+
+        Ok(content)
+    }
+
+    fn locate_file(zip: &ZipArchive, filename: &str) -> Result<i64> {
+        // return root composer.json if it is there and is a file
+        if let Some(index) = zip.locate_name(filename) {
+            if zip.get_from_index(index).is_some() {
+                return Ok(index);
+            }
+        }
+
+        let mut top_level_paths: IndexMap<String, bool> = IndexMap::new();
+        for i in 0..zip.num_files {
+            let name = zip.get_name_index(i);
+            let dir_name = dirname(&name);
+
+            // ignore OSX specific resource fork folder
+            if name.contains("__MACOSX") {
+                continue;
+            }
+
+            // handle archives with proper TOC
+            if dir_name == "." {
+                top_level_paths.insert(name, true);
+                if top_level_paths.len() > 1 {
+                    return Err(RuntimeException {
+                        message: format!(
+                            "Archive has more than one top level directories, and no composer.json was found on the top level, so it's an invalid archive. Top level paths found were: {}",
+                            implode(",", &top_level_paths.keys().cloned().collect::<Vec<_>>())
+                        ),
+                        code: 0,
+                    }
+                    .into());
+                }
+                continue;
+            }
+
+            // handle archives which do not have a TOC record for the directory itself
+            if !dir_name.contains('\\') && !dir_name.contains('/') {
+                top_level_paths.insert(format!("{}/", dir_name), true);
+                if top_level_paths.len() > 1 {
+                    return Err(RuntimeException {
+                        message: format!(
+                            "Archive has more than one top level directories, and no composer.json was found on the top level, so it's an invalid archive. Top level paths found were: {}",
+                            implode(",", &top_level_paths.keys().cloned().collect::<Vec<_>>())
+                        ),
+                        code: 0,
+                    }
+                    .into());
+                }
+            }
+        }
+
+        if !top_level_paths.is_empty() {
+            let first_key = top_level_paths.keys().next().unwrap().clone();
+            if let Some(index) = zip.locate_name(&format!("{}{}", first_key, filename)) {
+                if zip.get_from_index(index).is_some() {
+                    return Ok(index);
+                }
+            }
+        }
+
+        Err(RuntimeException {
+            message: "No composer.json found either at the top level or within the topmost directory"
+                .to_string(),
+            code: 0,
+        }
+        .into())
+    }
+}