Dev (#1)

Reviewed-on: #1

src/model/layout.rs

@@ -0,0 +1,98 @@
+// SPDX-License-Identifier: Prosperity-3.0.0
+// Copyright Scientific Computing Studio
+// Source: https://git.scient.ing/education/coursebank
+
+//! The on-disk layout of a course directory.
+
+use std::path::PathBuf;
+
+use crate::course::COURSE_FILE;
+use crate::error::{Error, Result};
+
+/// The standard directory layout of a course, resolved from a root.
+#[derive(Debug, Clone)]
+pub struct Layout {
+    /// The course root.
+    pub root: PathBuf,
+}
+
+impl Layout {
+    /// Builds a layout from a course root directory.
+    ///
+    /// # Arguments
+    ///
+    /// * `root` - the course directory.
+    ///
+    /// # Returns
+    ///
+    /// The layout.
+    pub fn new(root: impl Into<PathBuf>) -> Layout {
+        Layout { root: root.into() }
+    }
+
+    /// Path to `course.yaml`.
+    pub fn course_file(&self) -> PathBuf {
+        self.root.join(COURSE_FILE)
+    }
+
+    /// Directory holding item bank YAML files.
+    pub fn banks(&self) -> PathBuf {
+        self.root.join("banks")
+    }
+
+    /// Directory holding assessment records.
+    pub fn assessments(&self) -> PathBuf {
+        self.root.join("assessments")
+    }
+
+    /// Directory holding response tables and derived statistics.
+    pub fn data(&self) -> PathBuf {
+        self.root.join("data")
+    }
+
+    /// Directory holding generated reports.
+    pub fn reports(&self) -> PathBuf {
+        self.root.join("reports")
+    }
+
+    /// Directory holding generated exports such as QTI packages.
+    pub fn build(&self) -> PathBuf {
+        self.root.join("build")
+    }
+
+    /// Directory holding emitted JSON Schema files for editor validation.
+    pub fn schema(&self) -> PathBuf {
+        self.root.join("schema")
+    }
+
+    /// Directory holding Typst export templates and their configuration.
+    ///
+    /// Unlike the other directories, this one is *not* created by
+    /// [`Layout::create_all`]. Its absence is meaningful: a course with no
+    /// `templates/` directory uses the templates compiled into the binary, and
+    /// creating an empty one on `init` would suggest a customization step is
+    /// required when it is not. `coursebank template dump` creates it on demand.
+    pub fn templates(&self) -> PathBuf {
+        self.root.join("templates")
+    }
+
+    /// Creates every directory in the layout.
+    ///
+    /// # Errors
+    ///
+    /// Returns [`Error::Io`] if a directory cannot be created.
+    pub fn create_all(&self) -> Result<()> {
+        for dir in [
+            self.root.clone(),
+            self.banks(),
+            self.assessments(),
+            self.data(),
+            self.reports(),
+            self.build(),
+            self.schema(),
+        ] {
+            std::fs::create_dir_all(&dir).map_err(|e| Error::io(&dir, e))?;
+        }
+        Ok(())
+    }
+}