1 files changed, 87 insertions, 0 deletions
diff --git a/src/main/kotlin/moe/nea/blog/gen/MD2HtmlGenerator.kt b/src/main/kotlin/moe/nea/blog/gen/MD2HtmlGenerator.kt
new file mode 100644
index 0000000..0077469
--- /dev/null
+++ b/src/main/kotlin/moe/nea/blog/gen/MD2HtmlGenerator.kt
@@ -0,0 +1,87 @@
+package moe.nea.blog.gen
+
+import moe.nea.blog.md.Begin
+import moe.nea.blog.md.Bold
+import moe.nea.blog.md.CodeBlock
+import moe.nea.blog.md.Document
+import moe.nea.blog.md.FormatSequence
+import moe.nea.blog.md.Header
+import moe.nea.blog.md.Italics
+import moe.nea.blog.md.Link
+import moe.nea.blog.md.MarkdownElement
+import moe.nea.blog.md.Paragraph
+import moe.nea.blog.md.Whitespace
+import moe.nea.blog.md.Word
+import kotlin.reflect.KClass
+
+
+class MD2HtmlGenerator {
+	private val generators = mutableMapOf<KClass<out MarkdownElement>, HtmlFragmentGenerator<MarkdownElement>>()
+
+	fun <T : MarkdownElement> getGeneratorFor(kClass: KClass<out T>) = generators[kClass] as HtmlFragmentGenerator<T>?
+
+	inline fun <reified T : MarkdownElement> registerFragmentGenerator(noinline outputter: HtmlDsl.(generator: MD2HtmlGenerator, node: T) -> Unit) {
+		registerGeneratorFor(T::class) { gen, node ->
+			HtmlDsl()
+				.apply { outputter.invoke(this, gen, node) }
+				.intoFragment()
+		}
+	}
+
+	inline fun <reified T : MarkdownElement> registerGeneratorFor(outputter: HtmlFragmentGenerator<T>) {
+		registerGeneratorFor(T::class, outputter)
+	}
+
+	fun <T : MarkdownElement> registerGeneratorFor(kClass: KClass<T>, outputter: HtmlFragmentGenerator<T>) {
+		generators[kClass] = outputter as HtmlFragmentGenerator<MarkdownElement>
+	}
+
+	fun registerDefaultGenerators() {
+		registerGeneratorFor<Begin> { _, _ -> HtmlFragment.empty() }
+		registerFragmentGenerator<Header> { gen, header ->
+			element("h${header.level}", mapOf()) {
+				+header.text
+			}
+		}
+		registerFragmentGenerator<Bold> { gen, node ->
+			element("b", mapOf(), gen.generateHtml(node.inner))
+		}
+		registerFragmentGenerator<Italics> { generator, node ->
+			element("em", mapOf(), generator.generateHtml(node.inner))
+		}
+		registerFragmentGenerator<Link> { generator, node ->
+			element("a", mapOf("href" to node.target), generator.generateHtml(node.label ?: Begin()))
+		}
+		registerFragmentGenerator<Paragraph> { generator, node ->
+			element("p", mapOf(), generator.generateHtml(node.format))
+		}
+		registerFragmentGenerator<CodeBlock> { generator, node ->
+			element("pre", mapOf()) {
+				element("code", mapOf("class" to "language-${node.language}")) {
+					append(node.lines.joinToString("\n"))
+				}
+			}
+		}
+		registerFragmentGenerator<FormatSequence> { generator, node ->
+			for (markdownFormat in node.list) {
+				append(generator.generateHtml(markdownFormat))
+			}
+		}
+		registerFragmentGenerator<Word> { generator, node ->
+			append(node.text)
+		}
+		registerFragmentGenerator<Whitespace> { generator, node ->
+			append(" ")
+		}
+		registerFragmentGenerator<Document> { generator, node ->
+			for (markdownBlock in node.list) {
+				append(generator.generateHtml(markdownBlock))
+			}
+		}
+	}
+
+	fun <T : MarkdownElement> generateHtml(node: T): HtmlFragment {
+		val gen = getGeneratorFor(node::class) ?: error("Missing html generator for $node")
+		return gen.generateHtml(this, node)
+	}
+}
+\ No newline at end of file