add content types and multipart parser

src/main/java/io/github/lumijiez/core/http/HttpContentType.java

@@ -0,0 +1,28 @@
+package io.github.lumijiez.core.http;
+
+public enum HttpContentType {
+    TEXT_PLAIN("text/plain"),
+    APPLICATION_JSON("application/json"),
+    APPLICATION_XML("application/xml"),
+    MULTIPART_FORM_DATA("multipart/form-data"),
+    APPLICATION_FORM_URLENCODED("application/x-www-form-urlencoded");
+
+    private final String value;
+
+    HttpContentType(String value) {
+        this.value = value;
+    }
+
+    public String getValue() {
+        return value;
+    }
+
+    public static HttpContentType fromString(String value) {
+        for (HttpContentType type : values()) {
+            if (type.value.equalsIgnoreCase(value)) {
+                return type;
+            }
+        }
+        return TEXT_PLAIN;
+    }
+}

src/main/java/io/github/lumijiez/core/http/HttpMultipartParser.java

@@ -0,0 +1,62 @@
+package io.github.lumijiez.core.http;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+
+public class HttpMultipartParser {
+    private final String boundary;
+    private final BufferedReader reader;
+    private final Map<String, String> parts = new HashMap<>();
+
+    public HttpMultipartParser(BufferedReader reader, String contentType) {
+        this.reader = reader;
+        this.boundary = extractBoundary(contentType);
+    }
+
+    private String extractBoundary(String contentType) {
+        String[] parts = contentType.split(";");
+        for (String part : parts) {
+            if (part.trim().startsWith("boundary=")) {
+                return "--" + part.split("=")[1].trim();
+            }
+        }
+        return null;
+    }
+
+    public Map<String, String> parse() throws IOException {
+        String line;
+        StringBuilder content = new StringBuilder();
+        String currentName = null;
+
+        while ((line = reader.readLine()) != null) {
+            if (line.startsWith(boundary)) {
+                if (currentName != null) {
+                    parts.put(currentName, content.toString().trim());
+                    content = new StringBuilder();
+                }
+
+                while ((line = reader.readLine()) != null && !line.isEmpty()) {
+                    if (line.toLowerCase().startsWith("content-disposition:")) {
+                        currentName = extractFieldName(line);
+                    }
+                }
+            } else if (!line.equals(boundary + "--")) {
+                content.append(line).append("\n");
+            }
+        }
+
+        return parts;
+    }
+
+    private String extractFieldName(String header) {
+        String[] parts = header.split(";");
+        for (String part : parts) {
+            if (part.trim().startsWith("name=")) {
+                return part.split("=")[1].trim().replace("\"", "");
+            }
+        }
+        return null;
+    }
+}