Turn Result into a minimal interface

1 files changed, 69 insertions, 0 deletions

diff --git a/src/main/java/org/zwobble/mammoth/internal/results/InternalResult.java b/src/main/java/org/zwobble/mammoth/internal/results/InternalResult.java
new file mode 100644
index 0000000..b3c9ec7
--- /dev/null
+++ b/src/main/java/org/zwobble/mammoth/internal/results/InternalResult.java
@@ -0,0 +1,69 @@
+package org.zwobble.mammoth.internal.results;
+
+import com.google.common.collect.ImmutableList;
+import org.zwobble.mammoth.internal.documents.Style;
+import org.zwobble.mammoth.internal.util.MammothLists;
+
+import java.util.List;
+import java.util.Optional;
+import java.util.function.BiFunction;
+import java.util.function.Function;
+
+import static org.zwobble.mammoth.internal.util.MammothLists.list;
+
+public class InternalResult<T> implements org.zwobble.mammoth.Result<T> {
+    public static <T> InternalResult<List<T>> concat(Iterable<InternalResult<T>> results) {
+        ImmutableList.Builder<T> elements = ImmutableList.builder();
+        ImmutableList.Builder<Warning> warnings = ImmutableList.builder();
+        for (InternalResult<T> result : results) {
+            elements.add(result.value);
+            warnings.addAll(result.warnings);
+        }
+        return new InternalResult<>(elements.build(), warnings.build());
+    }
+
+    public static <T1, T2, R> InternalResult<R> map(
+        InternalResult<T1> first,
+        InternalResult<T2> second,
+        BiFunction<T1, T2, R> function)
+    {
+        return new InternalResult<>(
+            function.apply(first.value, second.value),
+            MammothLists.concat(first.warnings, second.warnings));
+    }
+
+    public static InternalResult<Optional<Style>> empty() {
+        return new InternalResult<>(Optional.empty(), list());
+    }
+
+    public static <T> InternalResult<T> success(T value) {
+        return new InternalResult<>(value, list());
+    }
+
+    private final T value;
+    private final List<Warning> warnings;
+
+    public InternalResult(T value, List<Warning> warnings) {
+        this.value = value;
+        this.warnings = warnings;
+    }
+
+    public T getValue() {
+        return value;
+    }
+
+    public List<Warning> getWarnings() {
+        return warnings;
+    }
+
+    public <R> InternalResult<R> map(Function<T, R> function) {
+        return new InternalResult<>(function.apply(value), warnings);
+    }
+
+    public <R> InternalResult<R> flatMap(Function<T, InternalResult<R>> function) {
+        InternalResult<R> intermediateResult = function.apply(value);
+        return new InternalResult<>(
+            intermediateResult.value,
+            MammothLists.concat(warnings, intermediateResult.warnings));
+    }
+}