Implement UserId.parse(mailbox)

pgpainless-core/src/main/java/org/pgpainless/key/util/UserId.java

@@ -5,10 +5,21 @@
 package org.pgpainless.key.util;
 
 import java.util.Comparator;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 
 public final class UserId implements CharSequence {
+
+    private static final Pattern emailPattern = Pattern.compile("(?:[\\p{L}\\u0900-\\u097F0-9!#\\$%&'*+/=?^_`{|}~-]+(?:\\.[\\p{L}\\u0900-\\u097F0-9!#\\$%&'*+/=?^_`{|}~-]+)*|\"(?:[\\x01-\\x08\\x0b\\x0c\\x0e-" +
+            "\\x1f\\x21\\x23-\\x5b\\x5d-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])*\")@(?:(?:[\\p{L}\\u0900-\\u097F0-9](?:[\\p{L}\\u0900-\\u097F0-9" +
+            "-]*[\\p{L}\\u0900-\\u097F0-9])?\\.)+[\\p{L}\\u0900-\\u097F0-9](?:[\\p{L}\\u0900-\\u097F0-9-]*[\\p{L}\\u0900-\\u097F0-9])?|\\[(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)" +
+            "\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?|[$\\p{L}\\u0900-\\u097F0-9-]*[\\p{L}\\u0900-\\u097F0-9]:(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f" +
+            "\\x21-\\x5a\\x53-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])+)])");
+
+    private static final Pattern nameAddrPattern = Pattern.compile("^((?<name>.+?)\\s)?(\\((?<comment>.+?)\\)\\s)?(<(?<email>.+?)>)?$");
+
     public static final class Builder {
         private String name;
         private String comment;
@@ -58,6 +69,37 @@ public final class UserId implements CharSequence {
         }
     }
 
+    public static UserId parse(@Nonnull String string) {
+        Builder builder = newBuilder();
+        string = string.trim();
+        Matcher matcher = nameAddrPattern.matcher(string);
+        if (matcher.find()) {
+            String name = matcher.group("name");
+            String comment = matcher.group("comment");
+            String mail = matcher.group("email");
+            matcher = emailPattern.matcher(mail);
+            if (!matcher.matches()) {
+                throw new IllegalArgumentException("Malformed email address");
+            }
+
+            if (name != null) {
+                builder.withName(name);
+            }
+            if (comment != null) {
+                builder.withComment(comment);
+            }
+            builder.withEmail(mail);
+        } else {
+            matcher = emailPattern.matcher(string);
+            if (matcher.matches()) {
+                builder.withEmail(string);
+            } else {
+                throw new IllegalArgumentException("Malformed email address");
+            }
+        }
+        return builder.build();
+    }
+
     private final String name;
     private final String comment;
     private final String email;
@@ -86,6 +128,24 @@ public final class UserId implements CharSequence {
     }
 
     public String getName() {
+        return getName(false);
+    }
+
+    public String getName(boolean preserveQuotes) {
+        if (name == null || name.isEmpty()) {
+            return name;
+        }
+
+        if (name.startsWith("\"")) {
+            if (preserveQuotes) {
+                return name;
+            }
+            String withoutQuotes = name.substring(1);
+            if (withoutQuotes.endsWith("\"")) {
+                withoutQuotes = withoutQuotes.substring(0, withoutQuotes.length() - 1);
+            }
+            return withoutQuotes;
+        }
         return name;
     }
 
@@ -116,7 +176,7 @@ public final class UserId implements CharSequence {
     public @Nonnull String toString() {
         StringBuilder sb = new StringBuilder();
         if (name != null && !name.isEmpty()) {
-            sb.append(name);
+            sb.append(getName(true));
         }
         if (comment != null && !comment.isEmpty()) {
             if (sb.length() > 0) {

pgpainless-core/src/test/java/org/pgpainless/key/UserIdTest.java

@@ -271,4 +271,114 @@ public class UserIdTest {
         assertNotEquals(0, UserId.compare(id1, id6, c));
         assertNotEquals(0, UserId.compare(id6, id1, c));
     }
+
+    @Test
+    public void parseNameAndEmail() {
+        UserId id = UserId.parse("Alice <alice@pgpainless.org>");
+
+        assertEquals("Alice", id.getName());
+        assertNull(id.getComment());
+        assertEquals("alice@pgpainless.org", id.getEmail());
+
+        assertEquals("Alice <alice@pgpainless.org>", id.toString());
+    }
+
+    @Test
+    public void parseNameCommentAndEmail() {
+        UserId id = UserId.parse("Alice (work mail) <alice@pgpainless.org>");
+
+        assertEquals("Alice", id.getName());
+        assertEquals("work mail", id.getComment());
+        assertEquals("alice@pgpainless.org", id.getEmail());
+
+        assertEquals("Alice (work mail) <alice@pgpainless.org>", id.toString());
+    }
+
+    @Test
+    public void parseLongNameAndEmail() {
+        UserId id = UserId.parse("Alice von Painleicester <alice@pgpainless.org>");
+
+        assertEquals("Alice von Painleicester", id.getName());
+        assertNull(id.getComment());
+        assertEquals("alice@pgpainless.org", id.getEmail());
+
+        assertEquals("Alice von Painleicester <alice@pgpainless.org>", id.toString());
+    }
+
+    @Test
+    public void parseLongNameCommentAndEmail() {
+        UserId id = UserId.parse("Alice von Painleicester (work email) <alice@pgpainless.org>");
+
+        assertEquals("Alice von Painleicester", id.getName());
+        assertEquals("work email", id.getComment());
+        assertEquals("alice@pgpainless.org", id.getEmail());
+
+        assertEquals("Alice von Painleicester (work email) <alice@pgpainless.org>", id.toString());
+    }
+
+    @Test
+    public void parseQuotedNameAndEmail() {
+        UserId id = UserId.parse("\"Alice\" <alice@pgpainless.org>");
+
+        assertEquals("Alice", id.getName());
+        assertNull(id.getComment());
+        assertEquals("alice@pgpainless.org", id.getEmail());
+
+        assertEquals("\"Alice\" <alice@pgpainless.org>", id.toString());
+    }
+
+    @Test
+    public void parseQuotedNameCommentAndEmail() {
+        UserId id = UserId.parse("\"Alice\" (work email) <alice@pgpainless.org>");
+
+        assertEquals("Alice", id.getName());
+        assertEquals("work email", id.getComment());
+        assertEquals("alice@pgpainless.org", id.getEmail());
+
+        assertEquals("\"Alice\" (work email) <alice@pgpainless.org>", id.toString());
+    }
+
+    @Test
+    public void parseLongQuotedNameAndEmail() {
+        UserId id = UserId.parse("\"Alice Mac Painlester\" <alice@pgpainless.org>");
+
+        assertEquals("Alice Mac Painlester", id.getName());
+        assertNull(id.getComment());
+        assertEquals("alice@pgpainless.org", id.getEmail());
+
+        assertEquals("\"Alice Mac Painlester\" <alice@pgpainless.org>", id.toString());
+    }
+
+    @Test
+    public void parseLongQuotedNameCommentAndEmail() {
+        UserId id = UserId.parse("\"Alice Mac Painlester\" (work email) <alice@pgpainless.org>");
+
+        assertEquals("Alice Mac Painlester", id.getName());
+        assertEquals("work email", id.getComment());
+        assertEquals("alice@pgpainless.org", id.getEmail());
+
+        assertEquals("\"Alice Mac Painlester\" (work email) <alice@pgpainless.org>", id.toString());
+    }
+
+    @Test
+    public void parseEmailOnly() {
+        UserId id = UserId.parse("alice@pgpainless.org");
+
+        assertNull(id.getName());
+        assertNull(id.getComment());
+        assertEquals("alice@pgpainless.org", id.getEmail());
+
+        assertEquals("<alice@pgpainless.org>", id.toString());
+    }
+
+    @Test
+    public void parseBracketedEmailOnly() {
+        UserId id = UserId.parse("<alice@pgpainless.org>");
+
+        assertNull(id.getName());
+        assertNull(id.getComment());
+        assertEquals("alice@pgpainless.org", id.getEmail());
+
+        assertEquals("<alice@pgpainless.org>", id.toString());
+    }
 }