src/main/kotlin/net/pterodactylus/sone/template/LinkedElementRenderFilter.kt

   1 package net.pterodactylus.sone.template
   2
   3 import net.pterodactylus.sone.core.*
   4 import net.pterodactylus.sone.utils.*
   5 import net.pterodactylus.util.template.*
   6 import java.io.*
   7
   8 /**
   9  * Renders all kinds of [LinkedElement]s.
  10  */
  11 class LinkedElementRenderFilter : Filter {
  12
  13         private val templateContextFactory = TemplateContextFactory().apply {
  14                 addFilter("html", HtmlFilter())
  15                 addProvider(ClassPathTemplateProvider(LinkedElementRenderFilter::class.java, "/templates/"))
  16         }
  17
  18         override fun format(templateContext: TemplateContext?, data: Any?, parameters: Map<String, Any?>?) =
  19                         when {
  20                                 data is LinkedElement && data.loading -> renderNotLoadedLinkedElement(data)
  21                                 data is LinkedElement && data.properties["type"] == "image" -> renderLinkedImage(data)
  22                                 data is LinkedElement && data.properties["type"] == "html" -> renderHtmlPage(data)
  23                                 else -> null
  24                         }
  25
  26         private fun renderLinkedImage(linkedElement: LinkedElement) =
  27                         StringWriter().use {
  28                                 val templateContext = templateContextFactory.createTemplateContext()
  29                                 templateContext["link"] = linkedElement.link
  30                                 it.also { loadedImageTemplate.render(templateContext, it) }
  31                         }.toString()
  32
  33         private fun renderHtmlPage(linkedElement: LinkedElement) =
  34                         StringWriter().use {
  35                                 val templateContext = templateContextFactory.createTemplateContext()
  36                                 templateContext["link"] = linkedElement.link
  37                                 templateContext["title"] = linkedElement.properties["title"] ?: "No title"
  38                                 templateContext["description"] = linkedElement.properties["description"] ?: "No description"
  39                                 it.also { loadedHtmlPageTemplate.render(templateContext, it) }
  40                         }.toString()
  41
  42         private fun renderNotLoadedLinkedElement(linkedElement: LinkedElement) =
  43                         StringWriter().use {
  44                                 val templateContext = templateContextFactory.createTemplateContext()
  45                                 templateContext["link"] = linkedElement.link
  46                                 it.also { notLoadedImageTemplate.render(templateContext, it) }
  47                         }.toString()
  48
  49 }
  50
  51 private val loadedImageTemplate = """<%include linked/image.html>""".asTemplate()
  52 private val loadedHtmlPageTemplate = """<%include linked/html-page.html>""".asTemplate()
  53 private val notLoadedImageTemplate = """<%include linked/notLoaded.html>""".asTemplate()