Coverage Summary for Class: KotlinxHtmlRenderer (io.heapy.kotmark.renderer.kotlinxhtml)

 package io.heapy.kotmark.renderer.kotlinxhtml
 
 import io.heapy.kotmark.KotmarkDsl
 import io.heapy.kotmark.internal.util.Escaping
 import io.heapy.kotmark.node.Node
 import io.heapy.kotmark.renderer.NodeRenderer
 import io.heapy.kotmark.renderer.Renderer
 import io.heapy.kotmark.renderer.html.AttributeProviderFactory
 import io.heapy.kotmark.renderer.html.DefaultUrlSanitizer
 import io.heapy.kotmark.renderer.html.UrlResolver
 import io.heapy.kotmark.renderer.html.UrlSanitizer
 import io.heapy.kotmark.renderer.kotlinxhtml.internal.CoreNodeRenderer
 import kotlinx.html.FlowContent
 import kotlinx.html.HTMLTag
 import kotlinx.html.TagConsumer
 import kotlinx.html.stream.appendHTML
 import kotlinx.html.visit
 import kotlin.reflect.KClass
 
 /** Renders AST nodes as kotlinx.html events. No syntax extension is loaded implicitly. */
 class KotlinxHtmlRenderer private constructor(configuration: Configuration) : Renderer {
     private val escapeHtml = configuration.escapeHtml
     private val sanitizeUrls = configuration.sanitizeUrls
     private val urlSanitizer = configuration.urlSanitizer
     private val urlResolver = configuration.urlResolver
     private val percentEncodeUrls = configuration.percentEncodeUrls
     private val omitSingleParagraphP = configuration.omitSingleParagraphP
     private val softbreak = configuration.softbreak
     private val factories = configuration.factories.toList() + KotlinxHtmlNodeRendererFactory(::CoreNodeRenderer)
     private val attributeFactories = configuration.attributeFactories.toList()
 
     override fun render(node: Node): String = buildString { render(node, this) }
 
     override fun render(node: Node, output: Appendable) {
         val consumer = output.appendHTML(prettyPrint = false)
         render(node, consumer)
         consumer.finalize()
     }
 
     /** Inserts into an open DSL container without finalizing or adding a wrapper. */
     fun render(node: Node, into: FlowContent) = render(node, into.consumer)
 
     /** Emits a fragment. The caller owns the consumer and its finalization. */
     fun render(node: Node, consumer: TagConsumer<*>) {
         val context = Context(consumer)
         context.renderers.forEach { it.beforeRoot(node) }
         context.render(node)
         context.renderers.forEach { it.afterRoot(node) }
     }
 
     @KotmarkDsl
     class Configuration internal constructor() {
         /** Raw Markdown HTML is escaped by default, including when rendering into a DOM. */
         var escapeHtml: Boolean = true
         var sanitizeUrls: Boolean = true
         var urlSanitizer: UrlSanitizer = DefaultUrlSanitizer()
         var urlResolver: UrlResolver? = null
         var percentEncodeUrls: Boolean = false
         var omitSingleParagraphP: Boolean = false
         /** Trusted replacement markup for soft breaks. The default is an ordinary newline. */
         var softbreak: String = "\n"
         internal val factories = mutableListOf<KotlinxHtmlNodeRendererFactory>()
         internal val attributeFactories = mutableListOf<AttributeProviderFactory>()
 
         /** First handler registered for a node type wins; core handlers come last. */
         fun nodeRendererFactory(factory: KotlinxHtmlNodeRendererFactory) {
             factories.add(factory)
         }
 
         fun attributeProviderFactory(factory: AttributeProviderFactory) {
             attributeFactories.add(factory)
         }
 
         fun adapters(vararg adapters: KotlinxHtmlAdapter) = adapters(adapters.asIterable())
 
         fun adapters(adapters: Iterable<KotlinxHtmlAdapter>) {
             adapters.forEach { it.extend(this) }
         }
 
         internal fun create(): KotlinxHtmlRenderer = KotlinxHtmlRenderer(this)
     }
 
     private inner class Context(override val consumer: TagConsumer<*>) : KotlinxHtmlNodeRendererContext {
         private var lastChar = '\u0000'
         private val providers = attributeFactories.map { it.create(this) }
         val renderers = factories.map { it.create(this) }
         private val handlers = buildMap<KClass<out Node>, NodeRenderer> {
             for (renderer in renderers) {
                 for (type in renderer.nodeTypes) {
                     if (type !in this) put(type, renderer)
                 }
             }
         }
 
         override val escapeHtml get() = this@KotlinxHtmlRenderer.escapeHtml
         override val sanitizeUrls get() = this@KotlinxHtmlRenderer.sanitizeUrls
         override val urlSanitizer get() = this@KotlinxHtmlRenderer.urlSanitizer
         override val omitSingleParagraphP get() = this@KotlinxHtmlRenderer.omitSingleParagraphP
         override val softbreak get() = this@KotlinxHtmlRenderer.softbreak
 
         override fun render(node: Node) {
             val renderer = handlers[node::class]
                 ?: error("No kotlinx.html handler for ${node::class}. Register its adapter explicitly.")
             renderer.render(node)
         }
 
         override fun renderChildren(parent: Node) {
             var child = parent.firstChild
             while (child != null) {
                 val next = child.next
                 render(child)
                 child = next
             }
         }
 
         override fun text(value: String) {
             // kotlinx.html 0.12 treats backslash + ampersand in one content event
             // as an escape hatch. Split the events to preserve literal Markdown text.
             var start = 0
             for (index in 1 until value.length) {
                 if (value[index] == '&' && value[index - 1] == '\\') {
                     consumer.onTagContent(value.substring(start, index))
                     start = index
                 }
             }
             consumer.onTagContent(value.substring(start))
             if (value.isNotEmpty()) lastChar = value.last()
         }
 
         override fun line() {
             if (!escapeHtml && lastChar != '\u0000' && lastChar != '\n') text("\n")
         }
 
         override fun raw(value: String) {
             if (value.isNotEmpty()) {
                 consumer.onTagContentUnsafe { +value }
                 lastChar = value.last()
             }
         }
 
         override fun resolveUrl(node: Node, destination: String): String =
             urlResolver?.resolveUrl(node, destination) ?: destination
 
         override fun encodeUrl(url: String): String =
             if (percentEncodeUrls) Escaping.percentEncodeUrl(url) else url
 
         override fun extendAttributes(node: Node, tagName: String, attributes: Map<String, String?>): Map<String, String?> =
             attributes.toMutableMap().also { result ->
                 providers.forEach { it.setAttributes(node, tagName, result) }
             }
 
         override fun element(node: Node, name: String, attributes: Map<String, String?>, block: FlowContent.() -> Unit) {
             require(TAG_NAME.matches(name)) { "Invalid HTML tag name: $name" }
             val attrs = extendAttributes(node, name, attributes).mapValues { it.value.orEmpty() }
             ContentTag(name, consumer, attrs).visit {
                 lastChar = '>'
                 block()
             }
             lastChar = '>'
         }
     }
 }
 
 private val TAG_NAME = Regex("[A-Za-z][A-Za-z0-9:-]*")
 private val VOID_TAGS = setOf("area", "base", "br", "col", "embed", "hr", "img", "input", "link", "meta", "param", "source", "track", "wbr")
 private val INLINE_TAGS = setOf("a", "br", "code", "del", "em", "img", "input", "ins", "mark", "span", "strong", "sub", "sup")
 
 private class ContentTag(name: String, consumer: TagConsumer<*>, attributes: Map<String, String>) :
     HTMLTag(name, consumer, attributes, inlineTag = name in INLINE_TAGS, emptyTag = name in VOID_TAGS), FlowContent
 
 /** Creates a renderer with a snapshot of the configured options and registrations. */
 fun kotlinxHtmlRenderer(configure: KotlinxHtmlRenderer.Configuration.() -> Unit = {}): KotlinxHtmlRenderer =
     KotlinxHtmlRenderer.Configuration().apply(configure).create()