1 files changed, 116 insertions, 0 deletions
diff --git a/plugins/base/src/main/kotlin/resolvers/DefaultLocationProvider.kt b/plugins/base/src/main/kotlin/resolvers/DefaultLocationProvider.kt
new file mode 100644
index 00000000..2238b0c3
--- /dev/null
+++ b/plugins/base/src/main/kotlin/resolvers/DefaultLocationProvider.kt
@@ -0,0 +1,116 @@
+package org.jetbrains.dokka.base.resolvers
+
+import org.jetbrains.dokka.links.DRI
+import org.jetbrains.dokka.pages.*
+import org.jetbrains.dokka.plugability.DokkaContext
+import org.jetbrains.dokka.utilities.htmlEscape
+import java.util.*
+
+private const val PAGE_WITH_CHILDREN_SUFFIX = "index"
+
+open class DefaultLocationProvider(
+    protected val pageGraphRoot: RootPageNode,
+    protected val dokkaContext: DokkaContext
+) : LocationProvider {
+    protected val extension = ".html"
+
+    protected val pagesIndex: Map<DRI, ContentPage> = pageGraphRoot.asSequence().filterIsInstance<ContentPage>()
+        .map { it.dri.map { dri -> dri to it } }.flatten()
+        .groupingBy { it.first }
+        .aggregate { dri, _, (_, page), first ->
+            if (first) page else throw AssertionError("Multiple pages associated with dri: $dri")
+        }
+
+    protected val pathsIndex: Map<PageNode, List<String>> = IdentityHashMap<PageNode, List<String>>().apply {
+        fun registerPath(page: PageNode, prefix: List<String>) {
+            val newPrefix = prefix + page.pathName
+            put(page, newPrefix)
+            page.children.forEach { registerPath(it, newPrefix) }
+        }
+        put(pageGraphRoot, emptyList())
+        pageGraphRoot.children.forEach { registerPath(it, emptyList()) }
+    }
+
+    override fun resolve(node: PageNode, context: PageNode?, skipExtension: Boolean): String =
+        pathTo(node, context) + if (!skipExtension) extension else ""
+
+    override fun resolve(dri: DRI, platforms: List<PlatformData>, context: PageNode?): String =
+        pagesIndex[dri]?.let { resolve(it, context) } ?:
+        // Not found in PageGraph, that means it's an external link
+        ExternalLocationProvider.getLocation(dri,
+            this.dokkaContext.configuration.passesConfigurations
+                .filter { passConfig ->
+                    platforms.toSet()
+                        .contains(PlatformData(passConfig.moduleName, passConfig.analysisPlatform, passConfig.targets))
+                } // TODO: change targets to something better?
+                .flatMap { it.externalDocumentationLinks }.distinct()
+        )
+
+    override fun resolveRoot(node: PageNode): String =
+        pathTo(pageGraphRoot, node).removeSuffix(PAGE_WITH_CHILDREN_SUFFIX)
+
+    override fun ancestors(node: PageNode): List<PageNode> =
+        generateSequence(node) { it.parent() }.toList()
+
+    protected open fun pathTo(node: PageNode, context: PageNode?): String {
+        fun pathFor(page: PageNode) = pathsIndex[page] ?: throw AssertionError(
+            "${page::class.simpleName}(${page.name}) does not belong to current page graph so it is impossible to compute its path"
+        )
+
+        val contextNode =
+            if (context?.children?.isEmpty() == true && context.parent() != null) context.parent() else context
+        val nodePath = pathFor(node)
+        val contextPath = contextNode?.let { pathFor(it) }.orEmpty()
+
+        val commonPathElements = nodePath.asSequence().zip(contextPath.asSequence())
+            .takeWhile { (a, b) -> a == b }.count()
+
+        return (List(contextPath.size - commonPathElements) { ".." } + nodePath.drop(commonPathElements) +
+                if (node.children.isNotEmpty()) listOf(PAGE_WITH_CHILDREN_SUFFIX) else emptyList()).joinToString("/")
+    }
+
+    private fun PageNode.parent() = pageGraphRoot.parentMap[this]
+}
+
+fun DRI.toJavadocLocation(jdkVersion: Int): String { // TODO: classes without packages?
+    val packageLink = packageName?.replace(".", "/")
+    if (classNames == null) {
+        return "$packageLink/package-summary.html".htmlEscape()
+    }
+    val classLink = if (packageLink == null) "$classNames.html" else "$packageLink/$classNames.html"
+    val callableChecked = callable ?: return classLink.htmlEscape()
+
+    val callableLink = "$classLink#${callableChecked.name}" + when {
+        jdkVersion < 8 -> "(${callableChecked.params.joinToString(", ")})"
+        jdkVersion < 10 -> "-${callableChecked.params.joinToString("-")}-"
+        else -> "(${callableChecked.params.joinToString(",")})"
+    }
+
+    return callableLink.htmlEscape()
+}
+
+fun DRI.toDokkaLocation(extension: String): String { // TODO: classes without packages?
+    val classNamesChecked = classNames ?: return "$packageName/index$extension"
+
+    val classLink = if (packageName == null) {
+        ""
+    } else {
+        "$packageName/"
+    } + classNamesChecked.split('.').joinToString("/", transform = ::identifierToFilename)
+
+    val callableChecked = callable ?: return "$classLink/index$extension"
+
+    return "$classLink/${identifierToFilename(callableChecked.name)}$extension"
+}
+
+private val reservedFilenames = setOf("index", "con", "aux", "lst", "prn", "nul", "eof", "inp", "out")
+
+private fun identifierToFilename(name: String): String {
+    if (name.isEmpty()) return "--root--"
+    val escaped = name.replace('<', '-').replace('>', '-')
+    val lowercase = escaped.replace("[A-Z]".toRegex()) { matchResult -> "-" + matchResult.value.toLowerCase() }
+    return if (lowercase in reservedFilenames) "--$lowercase--" else lowercase
+}
+
+private val PageNode.pathName: String
+    get() = if (this is PackagePageNode) name else identifierToFilename(name)