Add basic compilation to native C headers

2 files changed, 117 insertions, 0 deletions

diff --git a/src/main/java/org/shedlang/compiler/backends/Backends.java b/src/main/java/org/shedlang/compiler/backends/Backends.java
index f1d0abc4..0be1ecb2 100644
--- a/src/main/java/org/shedlang/compiler/backends/Backends.java
+++ b/src/main/java/org/shedlang/compiler/backends/Backends.java
@@ -17,6 +17,7 @@ public class Backends {
         Stream.of(
             LlvmBackend.AMD64,
             LlvmBackend.I686,
+            PatioNativeCHeadersBackend.INSTANCE,
             PatioTextBackend.INSTANCE,
             ShidTextBackend.INSTANCE,
             WasmBackend.WASM32,
diff --git a/src/main/java/org/shedlang/compiler/backends/PatioNativeCHeadersBackend.java b/src/main/java/org/shedlang/compiler/backends/PatioNativeCHeadersBackend.java
new file mode 100644
index 00000000..e483708b
--- /dev/null
+++ b/src/main/java/org/shedlang/compiler/backends/PatioNativeCHeadersBackend.java
@@ -0,0 +1,116 @@
+package org.shedlang.compiler.backends;
+
+import org.shedlang.compiler.backends.paths.PartialTargetPath;
+import org.shedlang.compiler.backends.paths.TargetDir;
+import org.shedlang.compiler.config.ProfileConfig;
+import org.shedlang.compiler.config.ProjectConfig;
+import org.shedlang.compiler.patio.PatioCompilationUnit;
+import org.shedlang.compiler.patio.PatioFunctionDeclaration;
+import org.shedlang.compiler.shid.ShidNamespace;
+import org.shedlang.compiler.typechecker.TypeInfos;
+import org.shedlang.compiler.types.NamespaceName;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.util.List;
+
+public class PatioNativeCHeadersBackend implements Backend {
+    public static final PatioNativeCHeadersBackend INSTANCE = new PatioNativeCHeadersBackend();
+
+    private PatioNativeCHeadersBackend() {
+    }
+
+    @Override
+    public String targetName() {
+        return "patio-native-c-headers";
+    }
+
+    public void compile(
+        ProjectConfig config,
+        ProfileConfig profileConfig,
+        List<ShidNamespace> namespaces,
+        TypeInfos typeInfos,
+        TargetDir targetDir
+    ) throws IOException, InterruptedException {
+        PatioBackends.compile(
+            config,
+            profileConfig,
+            namespaces,
+            typeInfos,
+            new PatioToNativeHeaders(targetDir)
+        );
+    }
+
+    private static class PatioToNativeHeaders implements PatioBackends.PatioToTarget {
+
+        private final TargetDir targetDir;
+
+        public PatioToNativeHeaders(TargetDir targetDir) {
+            this.targetDir = targetDir;
+        }
+
+        @Override
+        public PatioBackends.PatioToTarget namespace(
+            NamespaceName namespaceName,
+            PatioCompilationUnit patioCompilationUnit
+        ) throws IOException, InterruptedException {
+            serializeToDisk(
+                targetDir.namespace(namespaceName),
+                patioCompilationUnit
+            );
+
+            return this;
+        }
+
+        @Override
+        public void bin(
+            String binName,
+            PatioCompilationUnit patioCompilationUnit,
+            String mainFunctionName,
+            ProfileConfig profileConfig
+        ) throws IOException, InterruptedException {
+            serializeToDisk(
+                targetDir.bin(binName),
+                patioCompilationUnit
+            );
+        }
+
+        private void serializeToDisk(
+            PartialTargetPath partialTargetPath,
+            PatioCompilationUnit patioCompilationUnit
+        ) throws IOException {
+            var empty = true;
+
+            var builder = new StringBuilder();
+            // TODO: path to header file? Use angle brackets?
+            builder.append("#include \"shed.h\"\n");
+            for (var element : patioCompilationUnit.elements()) {
+                if (element instanceof PatioFunctionDeclaration patioFunctionDeclaration) {
+                    // TODO: pass this information through rather than having to inspect the string?
+                    // TODO: ignore dependency projects?
+                    if (patioFunctionDeclaration.name().startsWith("shed__runtime__namespace__")) {
+                        empty = false;
+                        builder.append("ShedObject ");
+                        builder.append(patioFunctionDeclaration.name());
+                        builder.append("(ShedClosurePointer closurePointer");
+                        for (var param : patioFunctionDeclaration.params()) {
+                            builder.append(", ShedObject ");
+                            builder.append(param.name());
+                        }
+                        builder.append(");\n");
+                    }
+                }
+            }
+
+            if (empty) {
+                return;
+            }
+
+            var compilationUnitString = builder.toString();
+
+            var path = partialTargetPath.withExtension(".h");
+            Files.createDirectories(path.getParent());
+            Files.writeString(path, compilationUnitString);
+        }
+    }
+}