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

   1 package net.pterodactylus.sone.template
   2
   3 import net.pterodactylus.sone.core.LinkedElement
   4 import net.pterodactylus.util.template.Filter
   5 import net.pterodactylus.util.template.TemplateContext
   6 import net.pterodactylus.util.template.TemplateContextFactory
   7 import net.pterodactylus.util.template.TemplateParser
   8 import java.io.StringReader
   9 import java.io.StringWriter
  10 import javax.inject.Inject
  11
  12 /**
  13  * Renders all kinds of [LinkedElement]s.
  14  */
  15 class LinkedElementRenderFilter @Inject constructor(private val templateContextFactory: TemplateContextFactory): Filter {
  16
  17         companion object {
  18                 private val loadedImageTemplate = """<%include linked/image.html>""".parse()
  19                 private val loadedHtmlPageTemplate = """<%include linked/html-page.html>""".parse()
  20                 private val notLoadedImageTemplate = """<%include linked/notLoaded.html>""".parse()
  21
  22                 private fun String.parse() = StringReader(this).use { TemplateParser.parse(it) }!!
  23         }
  24
  25         override fun format(templateContext: TemplateContext?, data: Any?, parameters: Map<String, Any?>?) =
  26                         when {
  27                                 data is LinkedElement && data.loading -> renderNotLoadedLinkedElement(data)
  28                                 data is LinkedElement && data.properties["type"] == "image" -> renderLinkedImage(data)
  29                                 data is LinkedElement && data.properties["type"] == "html" -> renderHtmlPage(data)
  30                                 else -> null
  31                         }
  32
  33         private fun renderLinkedImage(linkedElement: LinkedElement) =
  34                         StringWriter().use {
  35                                 val templateContext = templateContextFactory.createTemplateContext()
  36                                 templateContext["link"] = linkedElement.link
  37                                 it.also { loadedImageTemplate.render(templateContext, it) }
  38                         }.toString()
  39
  40         private fun renderHtmlPage(linkedElement: LinkedElement) =
  41                         StringWriter().use {
  42                                 val templateContext = templateContextFactory.createTemplateContext()
  43                                 templateContext["link"] = linkedElement.link
  44                                 templateContext["title"] = linkedElement.properties["title"] ?: "No title"
  45                                 templateContext["description"] = linkedElement.properties["description"] ?: "No description"
  46                                 it.also { loadedHtmlPageTemplate.render(templateContext, it) }
  47                         }.toString()
  48
  49         private fun renderNotLoadedLinkedElement(linkedElement: LinkedElement) =
  50                         StringWriter().use {
  51                                 val templateContext = templateContextFactory.createTemplateContext()
  52                                 templateContext["link"] = linkedElement.link
  53                                 it.also { notLoadedImageTemplate.render(templateContext, it) }
  54                         }.toString()
  55
  56 }