1 files changed, 46 insertions, 0 deletions
diff --git a/src/lock.rs b/src/lock.rs
new file mode 100644
index 0000000..3aaacac
--- /dev/null
+++ b/src/lock.rs
@@ -0,0 +1,46 @@
+use serde::{Deserialize, Serialize};
+use std::fs;
+
+pub const LOCK_PATH: &str = "/var/db/forge/forge.lock";
+
+#[derive(Deserialize, Serialize, Debug, Clone)]
+pub struct Package {
+    pub name: String,
+    pub source: String,
+    pub checksum: String,
+}
+
+#[derive(Deserialize, Serialize, Default)]
+pub struct Lockfile {
+    pub package: Vec<Package>,
+}
+
+impl Lockfile {
+    pub fn new() -> Self {
+        if let Ok(contents) = fs::read_to_string(LOCK_PATH) {
+            toml::from_str(&contents).unwrap_or_default()
+        } else {
+            Lockfile::default()
+        }
+    }
+
+    pub fn out_of_date(&self, update: Package) -> bool {
+        if let Some(existing) = self.package.iter().find(|p| p.name == update.name) {
+            return existing.checksum != update.checksum;
+        }
+        true
+    }
+
+    pub fn update_pkg(&mut self, package: Package) -> Result<(), String> {
+        if let Some(existing) = self.package.iter_mut().find(|p| p.name == package.name) {
+            *existing = package;
+        } else {
+            self.package.push(package);
+        }
+
+        let toml_string = toml::to_string_pretty(&self)
+            .map_err(|e| format!("failed to serialize lockfile: {e}"))?;
+
+        fs::write(LOCK_PATH, toml_string).map_err(|e| format!("failed to write to lockfile: {e}"))
+    }
+}