feat: add basic plan support

crates/forest/src/model.rs

@@ -0,0 +1,77 @@
+use std::path::PathBuf;
+
+use kdl::{KdlDocument, KdlNode, KdlValue};
+
+#[derive(Debug, Clone)]
+pub enum ProjectPlan {
+    Local { path: PathBuf },
+    NoPlan,
+}
+
+impl TryFrom<&KdlNode> for ProjectPlan {
+    type Error = anyhow::Error;
+
+    fn try_from(value: &KdlNode) -> Result<Self, Self::Error> {
+        let Some(children) = value.children() else {
+            return Ok(Self::NoPlan);
+        };
+
+        if let Some(local) = children.get_arg("local") {
+            return Ok(Self::Local {
+                path: local
+                    .as_string()
+                    .map(|l| l.to_string())
+                    .ok_or(anyhow::anyhow!("local must have an arg with a valid path"))?
+                    .into(),
+            });
+        }
+
+        Ok(Self::NoPlan)
+    }
+}
+
+#[derive(Debug, Clone)]
+pub struct Project {
+    pub name: String,
+    pub description: Option<String>,
+    pub plan: Option<ProjectPlan>,
+}
+
+impl TryFrom<KdlDocument> for Project {
+    type Error = anyhow::Error;
+
+    fn try_from(value: KdlDocument) -> Result<Self, Self::Error> {
+        let project_section = value.get("project").ok_or(anyhow::anyhow!(
+            "forest.kdl project file must have a project object"
+        ))?;
+
+        let project_children = project_section
+            .children()
+            .ok_or(anyhow::anyhow!("a forest project must have children"))?;
+
+        let project_plan: Option<ProjectPlan> = if let Some(project) = project_children.get("plan")
+        {
+            Some(project.try_into()?)
+        } else {
+            None
+        };
+
+        Ok(Self {
+            name: project_children
+                .get_arg("name")
+                .and_then(|n| match n {
+                    KdlValue::String(s) => Some(s),
+                    _ => None,
+                })
+                .cloned()
+                .ok_or(anyhow::anyhow!("a forest kuddle project must have a name"))?,
+            description: project_children
+                .get_arg("description")
+                .and_then(|n| match n {
+                    KdlValue::String(s) => Some(s.trim().to_string()),
+                    _ => None,
+                }),
+            plan: project_plan,
+        })
+    }
+}