Refactor parsers and data classes

- Move `PropStatParser` to object-based implementation
- Update `MultiStatusParser` and `ResponseParser` to use callback directly
- Remove redundant parameters from parsing functions

Author: rfc2822

src/main/kotlin/at/bitfire/dav4jvm/ktor/DavResource.kt

@@ -744,7 +744,7 @@ open class DavResource(
                 while (eventType != XmlPullParser.END_DOCUMENT) {
                     if (eventType == XmlPullParser.START_TAG && parser.depth == 1)
                         if (parser.propertyName() == WebDAV.MultiStatus) {
-                            return MultiStatusParser(location).parseResponse(parser, callback)
+                            return MultiStatusParser(location, callback).parseResponse(parser)
                             // further <multistatus> elements are ignored
                         }
 

src/main/kotlin/at/bitfire/dav4jvm/ktor/MultiStatusParser.kt

@@ -24,11 +24,13 @@ import org.xmlpull.v1.XmlPullParser
  * @param location  location of the request (used to resolve possible relative `<href>` in responses)
  */
 class MultiStatusParser(
-    private val location: Url
+    private val location: Url,
+    private val callback: MultiResponseCallback
 ) {
 
-    suspend fun parseResponse(parser: XmlPullParser, callback: MultiResponseCallback): List<Property> {
+    suspend fun parseResponse(parser: XmlPullParser): List<Property> {
         val responseProperties = mutableListOf<Property>()
+        val responseParser = ResponseParser(location, callback)
 
         // <!ELEMENT multistatus (response*, responsedescription?,
         //                        sync-token?) >
@@ -38,7 +40,7 @@ class MultiStatusParser(
             if (eventType == XmlPullParser.START_TAG && parser.depth == depth + 1)
                 when (parser.propertyName()) {
                     WebDAV.Response ->
-                        ResponseParser(location).parseResponse(parser, callback)
+                        responseParser.parseResponse(parser)
                     WebDAV.SyncToken ->
                         XmlReader(parser).readText()?.let {
                             responseProperties += SyncToken(it)

src/main/kotlin/at/bitfire/dav4jvm/ktor/PropStatParser.kt

@@ -17,7 +17,9 @@ import io.ktor.http.HttpStatusCode
 import org.xmlpull.v1.XmlPullParser
 import java.util.LinkedList
 
-class PropStatParser {
+object PropStatParser {
+
+    private val ASSUMING_OK = HttpStatusCode(200, "Assuming OK")
 
     fun parse(parser: XmlPullParser): PropStat {
         val depth = parser.depth
@@ -40,11 +42,4 @@ class PropStatParser {
         return PropStat(prop, status ?: ASSUMING_OK)
     }
 
-
-    companion object {
-
-        private val ASSUMING_OK = HttpStatusCode(200, "Assuming OK")
-
-    }
-
 }

src/main/kotlin/at/bitfire/dav4jvm/ktor/ResponseParser.kt

@@ -29,7 +29,8 @@ import java.util.logging.Logger
  * @param location  location of the request (used to resolve possible relative `<href>`)
  */
 class ResponseParser(
-    private val location: Url
+    private val location: Url,
+    private val callback: MultiResponseCallback
 ) {
 
     private val logger
@@ -46,13 +47,13 @@ class ResponseParser(
      * So if you want PROPFIND results to have a trailing slash when they are collections, make sure
      * that you query [at.bitfire.dav4jvm.property.webdav.ResourceType].
      */
-    suspend fun parseResponse(parser: XmlPullParser, callback: MultiResponseCallback) {
+    suspend fun parseResponse(parser: XmlPullParser) {
         val depth = parser.depth
 
         var hrefOrNull: Url? = null
         var status: HttpStatusCode? = null
         val propStat = mutableListOf<PropStat>()
-        var error: List<at.bitfire.dav4jvm.Error>? = null
+        var error: List<Error>? = null
         var newLocation: Url? = null
 
         var eventType = parser.eventType
@@ -83,8 +84,7 @@ class ResponseParser(
                             }
                         }
 
-
-                        if(!hierarchical) {
+                        if (!hierarchical) {
                             val urlBuilder = URLBuilder(location).takeFrom(sHref)
                             urlBuilder.pathSegments = urlBuilder.pathSegments.filterNot { it == "." } // Drop segments that are "./"
                             hrefOrNull = urlBuilder.build()
@@ -95,7 +95,7 @@ class ResponseParser(
                     WebDAV.Status ->
                         status = KtorHttpUtils.parseStatusLine(parser.nextText())
                     WebDAV.PropStat ->
-                        PropStatParser().parse(parser).let { propStat += it }
+                        PropStatParser.parse(parser).let { propStat += it }
                     WebDAV.Error ->
                         error = Error.parseError(parser)
                     WebDAV.Location ->