Add conversion of single paragraph documents

5 files changed, 69 insertions, 3 deletions

diff --git a/src/main/java/org/zwobble/mammoth/Mammoth.java b/src/main/java/org/zwobble/mammoth/Mammoth.java
index 5a2ed17..aa3514f 100644
--- a/src/main/java/org/zwobble/mammoth/Mammoth.java
+++ b/src/main/java/org/zwobble/mammoth/Mammoth.java
@@ -1,11 +1,57 @@
 package org.zwobble.mammoth;
 
+import java.io.File;
+import java.io.IOException;
 import java.io.InputStream;
+import java.util.zip.ZipFile;
+
+import org.zwobble.mammoth.xml.XmlElement;
+import org.zwobble.mammoth.xml.XmlNodeVisitor;
+import org.zwobble.mammoth.xml.XmlParser;
+import org.zwobble.mammoth.xml.XmlTextNode;
+
+import com.google.common.base.Joiner;
+import com.google.common.base.Strings;
+import com.google.common.collect.ImmutableBiMap;
+
+import static com.google.common.collect.Iterables.transform;
+
+import lombok.val;
 
 public class Mammoth {
 
-    public static String convertToHtml(InputStream stream) {
-        return "";
+    public static String convertToHtml(File file) {
+        try (val zipFile = new ZipFile(file)) {
+            val entry = zipFile.getEntry("word/document.xml");
+            val documentXml = parseXml(zipFile.getInputStream(entry));
+            val text = extractText(documentXml);
+            if (Strings.isNullOrEmpty(text)) {
+                return "";
+            } else {
+                return "<p>" + text + "</p>";                
+            }
+        } catch (IOException e) {
+            throw new UnsupportedOperationException("Should return a result of failure");   
+        }
+    }
+
+    private static XmlElement parseXml(InputStream inputStream) {
+        return new XmlParser(ImmutableBiMap.of()).parseStream(inputStream);
+    }
+
+    private static String extractText(XmlElement documentXml) {
+        return documentXml.accept(new XmlNodeVisitor<String>() {
+            @Override
+            public String visit(XmlElement element) {
+                return Joiner.on("").join(
+                    transform(element.children(), child -> child.accept(this)));
+            }
+
+            @Override
+            public String Visit(XmlTextNode textNode) {
+                return textNode.getValue();
+            }
+        });
     }
 
 }
diff --git a/src/main/java/org/zwobble/mammoth/xml/XmlElement.java b/src/main/java/org/zwobble/mammoth/xml/XmlElement.java
index a49f5f8..b5e8f1b 100644
--- a/src/main/java/org/zwobble/mammoth/xml/XmlElement.java
+++ b/src/main/java/org/zwobble/mammoth/xml/XmlElement.java
@@ -27,4 +27,13 @@ public class XmlElement implements XmlNode {
     private final String name;
     private final Map<String, String> attributes;
     private final List<XmlNode> children;
+    
+    @Override
+    public <T> T accept(XmlNodeVisitor<T> visitor) {
+        return visitor.visit(this);
+    }
+
+    public Iterable<XmlNode> children() {
+        return children;
+    }
 }
diff --git a/src/main/java/org/zwobble/mammoth/xml/XmlNode.java b/src/main/java/org/zwobble/mammoth/xml/XmlNode.java
index c91e100..37ce2cf 100644
--- a/src/main/java/org/zwobble/mammoth/xml/XmlNode.java
+++ b/src/main/java/org/zwobble/mammoth/xml/XmlNode.java
@@ -1,5 +1,5 @@
 package org.zwobble.mammoth.xml;
 
 public interface XmlNode {
-
+    <T> T accept(XmlNodeVisitor<T> visitor);
 }
diff --git a/src/main/java/org/zwobble/mammoth/xml/XmlNodeVisitor.java b/src/main/java/org/zwobble/mammoth/xml/XmlNodeVisitor.java
new file mode 100644
index 0000000..717e3db
--- /dev/null
+++ b/src/main/java/org/zwobble/mammoth/xml/XmlNodeVisitor.java
@@ -0,0 +1,6 @@
+package org.zwobble.mammoth.xml;
+
+public interface XmlNodeVisitor<T> {
+    T visit(XmlElement element);
+    T Visit(XmlTextNode textNode);
+}
diff --git a/src/main/java/org/zwobble/mammoth/xml/XmlTextNode.java b/src/main/java/org/zwobble/mammoth/xml/XmlTextNode.java
index 0d63273..4d47626 100644
--- a/src/main/java/org/zwobble/mammoth/xml/XmlTextNode.java
+++ b/src/main/java/org/zwobble/mammoth/xml/XmlTextNode.java
@@ -5,4 +5,9 @@ import lombok.Value;
 @Value
 public class XmlTextNode implements XmlNode {
     private String value;
+
+    @Override
+    public <T> T accept(XmlNodeVisitor<T> visitor) {
+        return visitor.Visit(this);
+    }
 }