build-tools: Implement compile_schemas helper for compiling GSettings schemas

It generates the `gschemas.compiled` file by copying all `.gschema.xml` files from the specified directories into the `glib-2.0/schemas` cache directory and then running `glib-compile-schemas --strict` to compile them.

Author: shahradelahi

glib-build-tools/src/lib.rs

@@ -2,7 +2,12 @@
 
 #![doc = include_str!("../README.md")]
 
-use std::{env, path::Path, process::Command};
+use gio::glib;
+use std::{
+    env,
+    path::{Path, PathBuf},
+    process::Command,
+};
 
 // rustdoc-stripper-ignore-next
 /// Call to run `glib-compile-resources` to generate compiled gresources to embed
@@ -57,3 +62,73 @@ pub fn compile_resources<P: AsRef<Path>>(source_dirs: &[P], gresource: &str, tar
         println!("cargo:rerun-if-changed={dep}");
     }
 }
+
+// rustdoc-stripper-ignore-next
+/// Call to run `glib-compile-schemas` to generate compiled gschemas from `.gschema.xml` schemas
+/// files from specified directories and store `gschemas.compiled` into `glib-2.0` schema cache
+/// directory.
+///
+/// ```no_run
+/// glib_build_tools::compile_schemas(
+///     &["schemas"],
+///     None
+/// );
+/// ```
+pub fn compile_schemas(schemas_dir: &[&str], target_dir: Option<&str>) {
+    // Target Directory
+    //  Unix - $HOME/.local/share/glib-2.0/schemas/
+    //  Windows - C:/ProgramData/glib-2.0/schemas/
+
+    let target_dir = match target_dir {
+        Some(base) => PathBuf::from(base),
+        None => {
+            let prefix = if cfg!(windows) {
+                PathBuf::from("C:/ProgramData")
+            } else {
+                glib::user_data_dir()
+            };
+
+            Path::new(&prefix).join("glib-2.0").join("schemas")
+        }
+    };
+
+    // Ensure target_dir exists
+    std::fs::create_dir_all(&target_dir).expect("Failed to create target directory");
+
+    // Recursively copy all files with .gschema.xml extension from schema_dir to target_dir
+    for schema_dir in schemas_dir {
+        let entries = Path::new(schema_dir)
+            .read_dir()
+            .expect("Failed to read schema directory")
+            .flatten();
+
+        for entry in entries {
+            let path = entry.path();
+            let file_name = path.file_name().unwrap().to_str().unwrap();
+
+            if path.is_file() && file_name.ends_with(".gschema.xml") {
+                let target_path = target_dir.join(path.file_name().unwrap());
+                std::fs::copy(&path, &target_path).expect("Failed to copy schema file");
+            }
+        }
+    }
+
+    let mut command = Command::new("glib-compile-schemas");
+    command.arg("--strict");
+    command.arg(target_dir);
+
+    let output = command
+        .output()
+        .expect("Failed to execute glib-compile-schemas");
+
+    assert!(
+        output.status.success(),
+        "glib-compile-schemas failed with exit status {} and stderr:\n{}",
+        output.status,
+        String::from_utf8_lossy(&output.stderr)
+    );
+
+    for schema_dir in schemas_dir {
+        println!("cargo:rerun-if-changed={}", schema_dir);
+    }
+}