Flatten multi-module structure (#1980)

* Add support for multimodule package lists

* Merge package-lists in multi-module generation

* Remove double-wrapping of modules in multi-module generation

* Handle empty modules in package lists

1 files changed, 35 insertions, 8 deletions

diff --git a/plugins/base/src/main/kotlin/resolvers/shared/PackageList.kt b/plugins/base/src/main/kotlin/resolvers/shared/PackageList.kt
index a06365eb..469904bd 100644
--- a/plugins/base/src/main/kotlin/resolvers/shared/PackageList.kt
+++ b/plugins/base/src/main/kotlin/resolvers/shared/PackageList.kt
@@ -1,20 +1,33 @@
 package org.jetbrains.dokka.base.resolvers.shared
 
-import org.jetbrains.dokka.base.renderers.PackageListService
 import java.net.URL
 
+typealias Module = String
+
 data class PackageList(
     val linkFormat: RecognizedLinkFormat,
-    val packages: Set<String>,
+    val modules: Map<Module, Set<String>>,
     val locations: Map<String, String>,
     val url: URL
 ) {
+    val packages: Set<String>
+        get() = modules.values.flatten().toSet()
+
+    fun moduleFor(packageName: String) = modules.asSequence()
+            .filter { it.value.contains(packageName) }
+            .firstOrNull()?.key
+
     companion object {
+        const val PACKAGE_LIST_NAME = "package-list"
+        const val MODULE_DELIMITER = "module:"
+        const val DOKKA_PARAM_PREFIX = "\$dokka"
+        const val SINGLE_MODULE_NAME = ""
+
         fun load(url: URL, jdkVersion: Int, offlineMode: Boolean = false): PackageList? {
             if (offlineMode && url.protocol.toLowerCase() != "file")
                 return null
 
-            val packageListStream = kotlin.runCatching { url.readContent() }.onFailure {
+            val packageListStream = runCatching { url.readContent() }.onFailure {
                 println("Failed to download package-list from $url, this might suggest that remote resource is not available," +
                         " module is empty or dokka output got corrupted")
                 return null
@@ -22,22 +35,36 @@ data class PackageList(
 
             val (params, packages) = packageListStream
                 .bufferedReader()
-                .useLines { lines -> lines.partition { it.startsWith(PackageListService.DOKKA_PARAM_PREFIX) } }
+                .useLines { lines -> lines.partition { it.startsWith(DOKKA_PARAM_PREFIX) } }
 
             val paramsMap = splitParams(params)
             val format = linkFormat(paramsMap["format"]?.singleOrNull(), jdkVersion)
             val locations = splitLocations(paramsMap["location"].orEmpty()).filterKeys(String::isNotEmpty)
 
-            return PackageList(format, packages.filter(String::isNotBlank).toSet(), locations, url)
+            val modulesMap = splitPackages(packages)
+            return PackageList(format, modulesMap, locations, url)
         }
 
         private fun splitParams(params: List<String>) = params.asSequence()
-            .map { it.removePrefix("${PackageListService.DOKKA_PARAM_PREFIX}.").split(":", limit = 2) }
+            .map { it.removePrefix("$DOKKA_PARAM_PREFIX.").split(":", limit = 2) }
             .groupBy({ (key, _) -> key }, { (_, value) -> value })
 
         private fun splitLocations(locations: List<String>) = locations.map { it.split("\u001f", limit = 2) }
-            .map { (key, value) -> key to value }
-            .toMap()
+                .associate { (key, value) -> key to value }
+
+        private fun splitPackages(packages: List<String>): Map<Module, Set<String>> =
+                packages.fold(("" to mutableMapOf<Module, Set<String>>())) { (lastModule, acc), el ->
+                    val currentModule : String
+                    when {
+                        el.startsWith(MODULE_DELIMITER) -> currentModule = el.substringAfter(MODULE_DELIMITER)
+                        el.isNotBlank() -> {
+                            currentModule = lastModule
+                            acc[currentModule] = acc.getOrDefault(lastModule, emptySet()) + el
+                        }
+                        else -> currentModule = lastModule
+                    }
+                    currentModule to acc
+                }.second
 
         private fun linkFormat(formatName: String?, jdkVersion: Int) =
             formatName?.let { RecognizedLinkFormat.fromString(it) }