Separate targets from backends

9 files changed, 139 insertions, 24 deletions

diff --git a/src/main/java/org/shedlang/compiler/backends/BackendFactory.java b/src/main/java/org/shedlang/compiler/backends/BackendFactory.java
new file mode 100644
index 00000000..b8fcdb46
--- /dev/null
+++ b/src/main/java/org/shedlang/compiler/backends/BackendFactory.java
@@ -0,0 +1,7 @@
+package org.shedlang.compiler.backends;
+
+import java.util.Optional;
+
+public interface BackendFactory {
+    Optional<Backend> backendForTarget(ShedTarget target);
+}
diff --git a/src/main/java/org/shedlang/compiler/backends/Backends.java b/src/main/java/org/shedlang/compiler/backends/Backends.java
index 0be1ecb2..d266302f 100644
--- a/src/main/java/org/shedlang/compiler/backends/Backends.java
+++ b/src/main/java/org/shedlang/compiler/backends/Backends.java
@@ -1,36 +1,37 @@
 package org.shedlang.compiler.backends;
 
-import org.pcollections.OrderedPMap;
-import org.shedlang.compiler.backends.llvm.LlvmBackend;
-import org.shedlang.compiler.backends.wasm.WasmBackend;
-import org.shedlang.compiler.util.PCollectors;
+import org.shedlang.compiler.backends.llvm.LlvmBackendFactory;
+import org.shedlang.compiler.backends.wasm.WasmBackendFactory;
 
-import java.util.Map;
-import java.util.Set;
-import java.util.stream.Stream;
+import java.util.List;
 
 public class Backends {
     private Backends() {
     }
 
-    private static final OrderedPMap<String, Backend> BACKENDS =
-        Stream.of(
-            LlvmBackend.AMD64,
-            LlvmBackend.I686,
-            PatioNativeCHeadersBackend.INSTANCE,
-            PatioTextBackend.INSTANCE,
-            ShidTextBackend.INSTANCE,
-            WasmBackend.WASM32,
-            WasmBackend.WASM64
-        )
-        .map(backend -> Map.entry(backend.targetName(), backend))
-        .collect(PCollectors.toOrderedPMap());
-
-    public static Set<String> targetNames() {
-        return BACKENDS.keySet();
+    private static final List<BackendFactory> BACKEND_FACTORIES = List.of(
+        new LlvmBackendFactory(),
+        new WasmBackendFactory(),
+        PatioNativeCHeadersBackend.FACTORY,
+        PatioTextBackend.FACTORY,
+        ShidTextBackend.FACTORY
+    );
+
+    public static List<String> targetNames() {
+        return ShedTarget.targetNames();
     }
 
     public static Backend backendForTarget(String targetName) {
-        return BACKENDS.get(targetName);
+        var target = ShedTarget.fromString(targetName)
+            .orElseThrow(() -> new UnsupportedOperationException("TODO"));
+
+        for (var factory : BACKEND_FACTORIES) {
+            var backend = factory.backendForTarget(target);
+            if (backend.isPresent()) {
+                return backend.get();
+            }
+        }
+
+        throw new UnsupportedOperationException("TODO");
     }
 }
diff --git a/src/main/java/org/shedlang/compiler/backends/PatioNativeCHeadersBackend.java b/src/main/java/org/shedlang/compiler/backends/PatioNativeCHeadersBackend.java
index 4f15c33d..ea8bde7c 100644
--- a/src/main/java/org/shedlang/compiler/backends/PatioNativeCHeadersBackend.java
+++ b/src/main/java/org/shedlang/compiler/backends/PatioNativeCHeadersBackend.java
@@ -13,8 +13,17 @@ import org.shedlang.compiler.types.NamespaceName;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.util.List;
+import java.util.Optional;
 
 public class PatioNativeCHeadersBackend implements Backend {
+    public static final BackendFactory FACTORY = target -> {
+        if (target == ShedTarget.PATIO_NATIVE_C_HEADERS) {
+            return Optional.of(PatioNativeCHeadersBackend.INSTANCE);
+        } else {
+            return Optional.empty();
+        }
+    };
+
     public static final PatioNativeCHeadersBackend INSTANCE = new PatioNativeCHeadersBackend();
 
     private PatioNativeCHeadersBackend() {
diff --git a/src/main/java/org/shedlang/compiler/backends/PatioTextBackend.java b/src/main/java/org/shedlang/compiler/backends/PatioTextBackend.java
index 052408c0..c2fe8708 100644
--- a/src/main/java/org/shedlang/compiler/backends/PatioTextBackend.java
+++ b/src/main/java/org/shedlang/compiler/backends/PatioTextBackend.java
@@ -13,8 +13,17 @@ import org.shedlang.compiler.types.NamespaceName;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.util.List;
+import java.util.Optional;
 
 public class PatioTextBackend implements Backend {
+    public static final BackendFactory FACTORY = target -> {
+        if (target == ShedTarget.PATIO_TEXT) {
+            return Optional.of(PatioTextBackend.INSTANCE);
+        } else {
+            return Optional.empty();
+        }
+    };
+
     public static final PatioTextBackend INSTANCE = new PatioTextBackend();
 
     private PatioTextBackend() {
diff --git a/src/main/java/org/shedlang/compiler/backends/ShedTarget.java b/src/main/java/org/shedlang/compiler/backends/ShedTarget.java
new file mode 100644
index 00000000..d99de131
--- /dev/null
+++ b/src/main/java/org/shedlang/compiler/backends/ShedTarget.java
@@ -0,0 +1,41 @@
+package org.shedlang.compiler.backends;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Optional;
+
+public enum ShedTarget {
+    AMD64("amd64"),
+    I686("i686"),
+    WASM32("wasm32"),
+    WASM64("wasm64"),
+    PATIO_NATIVE_C_HEADERS("patio-native-c-headers"),
+    PATIO_TEXT("patio-text"),
+    SHID_TEXT("shid-text");
+
+    public static List<String> targetNames() {
+        return Arrays.stream(ShedTarget.class.getEnumConstants())
+            .map(ShedTarget::targetName)
+            .toList();
+    }
+
+    public static Optional<ShedTarget> fromString(String targetName) {
+        for (var target : ShedTarget.class.getEnumConstants()) {
+            if (target.targetName.equals(targetName)) {
+                return Optional.of(target);
+            }
+        }
+
+        return Optional.empty();
+    }
+
+    private final String targetName;
+
+    ShedTarget(String targetName) {
+        this.targetName = targetName;
+    }
+
+    public String targetName() {
+        return targetName;
+    }
+}
diff --git a/src/main/java/org/shedlang/compiler/backends/ShidTextBackend.java b/src/main/java/org/shedlang/compiler/backends/ShidTextBackend.java
index f34c18b2..7468336f 100644
--- a/src/main/java/org/shedlang/compiler/backends/ShidTextBackend.java
+++ b/src/main/java/org/shedlang/compiler/backends/ShidTextBackend.java
@@ -10,8 +10,17 @@ import org.shedlang.compiler.typechecker.TypeInfos;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.util.List;
+import java.util.Optional;
 
 public class ShidTextBackend implements Backend {
+    public static final BackendFactory FACTORY = target -> {
+        if (target == ShedTarget.SHID_TEXT) {
+            return Optional.of(ShidTextBackend.INSTANCE);
+        } else {
+            return Optional.empty();
+        }
+    };
+
     public static final ShidTextBackend INSTANCE = new ShidTextBackend();
 
     private ShidTextBackend() {
diff --git a/src/main/java/org/shedlang/compiler/backends/llvm/LlvmBackendFactory.java b/src/main/java/org/shedlang/compiler/backends/llvm/LlvmBackendFactory.java
new file mode 100644
index 00000000..bb8a952a
--- /dev/null
+++ b/src/main/java/org/shedlang/compiler/backends/llvm/LlvmBackendFactory.java
@@ -0,0 +1,20 @@
+package org.shedlang.compiler.backends.llvm;
+
+import org.shedlang.compiler.backends.Backend;
+import org.shedlang.compiler.backends.BackendFactory;
+import org.shedlang.compiler.backends.ShedTarget;
+
+import java.util.Optional;
+
+public class LlvmBackendFactory implements BackendFactory {
+    @Override
+    public Optional<Backend> backendForTarget(ShedTarget target) {
+        Optional<LlvmTarget> llvmTarget = switch (target) {
+            case AMD64 -> Optional.of(LlvmTarget.AMD64);
+            case I686 -> Optional.of(LlvmTarget.I686);
+            default -> Optional.empty();
+        };
+
+        return llvmTarget.map(LlvmBackend::forTarget);
+    }
+}
diff --git a/src/main/java/org/shedlang/compiler/backends/wasm/WasmBackendFactory.java b/src/main/java/org/shedlang/compiler/backends/wasm/WasmBackendFactory.java
new file mode 100644
index 00000000..5cf8446f
--- /dev/null
+++ b/src/main/java/org/shedlang/compiler/backends/wasm/WasmBackendFactory.java
@@ -0,0 +1,20 @@
+package org.shedlang.compiler.backends.wasm;
+
+import org.shedlang.compiler.backends.Backend;
+import org.shedlang.compiler.backends.BackendFactory;
+import org.shedlang.compiler.backends.ShedTarget;
+
+import java.util.Optional;
+
+public class WasmBackendFactory implements BackendFactory {
+    @Override
+    public Optional<Backend> backendForTarget(ShedTarget target) {
+        Optional<WasmTarget> wasmTarget = switch (target) {
+            case WASM32 -> Optional.of(WasmTarget.WASM32);
+            case WASM64 -> Optional.of(WasmTarget.WASM64);
+            default -> Optional.empty();
+        };
+
+        return wasmTarget.map(WasmBackend::forTarget);
+    }
+}
diff --git a/src/main/java/org/shedlang/compiler/cli/ShedCli.java b/src/main/java/org/shedlang/compiler/cli/ShedCli.java
index c311e7bd..46bf9b5f 100644
--- a/src/main/java/org/shedlang/compiler/cli/ShedCli.java
+++ b/src/main/java/org/shedlang/compiler/cli/ShedCli.java
@@ -10,7 +10,6 @@ import org.shedlang.compiler.errors.CompilerError;
 
 import java.io.IOException;
 import java.nio.file.Path;
-import java.nio.file.Paths;
 import java.util.Optional;
 
 public class ShedCli {