command reader: json reading

src/main/java/de/bixilon/minosoft/commands/util/CommandReader.kt

@@ -14,6 +14,7 @@
 package de.bixilon.minosoft.commands.util
 
 import de.bixilon.kutil.cast.CastUtil.unsafeCast
+import de.bixilon.kutil.json.JsonObject
 import de.bixilon.minosoft.commands.errors.reader.*
 import de.bixilon.minosoft.commands.errors.reader.map.DuplicatedKeyMapError
 import de.bixilon.minosoft.commands.errors.reader.map.ExpectedKeyMapError
@@ -22,6 +23,7 @@ import de.bixilon.minosoft.commands.errors.reader.map.InvalidMapSeparatorError
 import de.bixilon.minosoft.commands.errors.reader.number.NegativeNumberError
 import de.bixilon.minosoft.data.registries.ResourceLocation
 import de.bixilon.minosoft.util.KUtil.toResourceLocation
+import de.bixilon.minosoft.util.json.Jackson
 
 open class CommandReader(val string: String) {
     var pointer = 0
@@ -359,6 +361,12 @@ open class CommandReader(val string: String) {
         return map
     }
 
+
+    fun readJson(): JsonObject {
+        skipWhitespaces()
+        return Jackson.MAPPER.readValue(JsonReader(this), Jackson.JSON_MAP_TYPE)
+    }
+
     override fun toString(): String {
         return string.substring(pointer, string.length)
     }

src/main/java/de/bixilon/minosoft/commands/util/JsonReader.kt

@@ -0,0 +1,26 @@
+/*
+ * Minosoft
+ * Copyright (C) 2020-2022 Moritz Zwerger
+ *
+ * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * This software is not affiliated with Mojang AB, the original developer of Minecraft.
+ */
+
+package de.bixilon.minosoft.commands.util
+
+import java.io.Reader
+
+class JsonReader(val reader: CommandReader) : Reader() {
+
+    override fun read(cbuf: CharArray, off: Int, len: Int): Int {
+        cbuf[0] = reader.readNext()?.toChar() ?: return 0
+        return 1
+    }
+
+    override fun close() = Unit
+}

src/test/java/de/bixilon/minosoft/commands/util/CommandReaderTest.kt

@@ -182,4 +182,23 @@ internal class CommandReaderTest {
         assertEquals(read, "not")
         assertFalse(negated)
     }
+
+    @Test
+    fun readEmptyJson() {
+        val reader = CommandReader("{}")
+        assertEquals(reader.readJson(), emptyMap())
+    }
+
+    @Test
+    fun readBasicJson() {
+        val reader = CommandReader("""{"test": 123}""")
+        assertEquals(reader.readJson(), mapOf("test" to 123))
+    }
+
+    @Test
+    fun readJsonWithTrailingData() {
+        val reader = CommandReader("""{"test": 123} abc""")
+        assertEquals(reader.readJson(), mapOf("test" to 123))
+        assertEquals(reader.readString(), "abc")
+    }
 }