import org.springframework.web.context.request.RequestContextHolder as RCH

import org.codehaus.groovy.grails.commons.GrailsClass
import org.codehaus.groovy.grails.plugins.PluginMetaManager
import org.codehaus.groovy.grails.plugins.web.ControllersGrailsPlugin
import org.codehaus.groovy.grails.web.metaclass.BindDynamicMethod
import org.codehaus.groovy.grails.web.plugins.support.WebMetaUtils
import org.springframework.aop.framework.ProxyFactoryBean
import org.springframework.aop.target.HotSwappableTargetSource
import org.springframework.beans.factory.config.MethodInvokingFactoryBean
import org.springframework.context.ApplicationContext
import org.springframework.web.context.request.RequestAttributes
import org.codehaus.grails.portlets.*

class PortletsGrailsPlugin {

    // the plugin version
    def version = "0.9.1"
    // the version or versions of Grails the plugin is designed for
    def grailsVersion = "1.3 > *"
    // the other plugins this plugin depends on
    def loadAfter = ['controllers']

    def artefacts = [PortletArtefactHandler.class]
    // resources that are excluded from plugin packaging
    def pluginExcludes = [
            "grails-app/views/error.gsp"
    ]

    def author = "Kenji Nakamura"
    def authorEmail = "kenji_nakamura@diva-america.com"
    def title = "Portlets Plugin"
    def description = '''\\
Generate JSR-168 compliant portlet war. 
'''

    // URL to the plugin's documentation
    def documentation = "http://grails.org/plugins/portlets"

    static WEB_APP_NAME = 'Grails Portlet Application'

def watchedResources = [
           'file:./grails-app/portlets/**/*Portlet.groovy',
           'file:./plugins/*/grails-app/portlets/**/*Portlet.groovy'
   ]

   def doWithSpring = {

      application.portletClasses.each {portlet ->
         log.debug "Configuring portlet $portlet.fullName"

         "${portlet.fullName}Class"(MethodInvokingFactoryBean) {
            targetObject = ref("grailsApplication", true)
            targetMethod = "getArtefact"
            arguments = [PortletArtefactHandler.TYPE, portlet.fullName]
         }
         "${portlet.fullName}TargetSource"(HotSwappableTargetSource, ref("${portlet.fullName}Class"))

         "${portlet.fullName}Proxy"(ProxyFactoryBean) {
            targetSource = ref("${portlet.fullName}TargetSource")
            proxyInterfaces = [GrailsPortletClass.class]
         }
         "${portlet.fullName}"("${portlet.fullName}Proxy": "newInstance") {bean ->
            bean.singleton = false
            bean.autowire = "byName"
         }
      }
      portletHandlerMappings(GrailsPortletHandlerMapping) {
         interceptors = [ref("portletHandlerInterceptor")]
      }
      portletHandlerAdapter(GrailsPortletHandlerAdapter)
      portletReloadFilter(PortletReloadFilter)
      portletHandlerInterceptor(GrailsPortletHandlerInterceptor) {
         portletReloadFilter = ref(portletReloadFilter)
      }
   }

   def doWithWebDescriptor = {webXml ->
      def mappingElement = webXml.'servlet-mapping'
      mappingElement = mappingElement[mappingElement.size() - 1]

      mappingElement + {
         'servlet-mapping'
         {
            'servlet-name'('view-servlet')
            'url-pattern'('/WEB-INF/servlet/view')
         }
      }

      def servletElement = webXml.'servlet'
      servletElement = servletElement[servletElement.size() - 1]

      servletElement + {
         'servlet'
         {
            'servlet-name'('view-servlet')
            'servlet-class'('org.springframework.web.servlet.ViewRendererServlet')
            'load-on-startup'('1')
         }
      }
   }

   def doWithDynamicMethods = {ApplicationContext ctx ->
      def registry = GroovySystem.getMetaClassRegistry()

      def bind = new BindDynamicMethod()

      // add commons objects and dynamic methods like render and redirect to portlets
      for (GrailsClass portlet in application.portletClasses) {
         MetaClass mc = portlet.metaClass
         Class portletClass = portlet.clazz
         WebMetaUtils.registerCommonWebProperties(mc, application)
         def controllersPlugin = new ControllersGrailsPlugin()
         controllersPlugin.registerControllerMethods(mc, ctx)
         Class superClass = portletClass.superclass

         mc.getPluginContextPath = {->
            PluginMetaManager metaManager = ctx.pluginMetaManager
            String path = metaManager.getPluginPathForResource(delegate.class.name)
            path ? path : ''
         }

         mc.getPortletRequest = {
            getFromRequestAttributes('javax.portlet.request')
         }

         mc.getPortletResponse = {
            getFromRequestAttributes('javax.portlet.response')
         }

         mc.getMode = {
            def req = getFromRequestAttributes('javax.portlet.request')
            req.portletMode
         }

         mc.getSession = {
            def req = getFromRequestAttributes('javax.portlet.request')
            req.portletSession
         }

         mc.getWindowState = {
            def req = getFromRequestAttributes('javax.portlet.request')
            req.windowState
         }

         mc.getPortalContext = {
            def req = getFromRequestAttributes('javax.portlet.request')
            req.portalContext
         }

         mc.getPreferences = {
            def req = getFromRequestAttributes('javax.portlet.request')
            req.preferences
         }

         // deal with abstract super classes
         while (superClass != Object.class) {
            if (Modifier.isAbstract(superClass.getModifiers())) {
               WebMetaUtils.registerCommonWebProperties(superClass.metaClass, application)
               controllersPlugin.registerControllerMethods(superClass.metaClass, ctx)
            }
         }
      }
   }

   private getFromRequestAttributes(key) {
      def webRequest = RCH.currentRequestAttributes();
      webRequest.getAttribute(key,
              RequestAttributes.SCOPE_REQUEST)
   }

   def onChange = {event ->
      def context = event.ctx
      if (!context) {
         if (log.isDebugEnabled())
            log.debug("Application context not found. Can't reload")
         return
      }
      boolean isNew = application.getPortletClass(event.source?.name) ? false : true
      def portletClass = application.addArtefact(PortletArtefactHandler.TYPE, event.source)

      if (isNew) {
         log.info "Portlet ${event.source} found. You need to restart for the change to be applied"
      }
      else {
         if (log.isDebugEnabled()) {
            log.debug("Portlet ${event.source} changed. Reloading...")
         }

         def portletTargetSource = context.getBean("${portletClass.fullName}TargetSource")
         portletTargetSource.swap(portletClass)
      }
      event.manager?.getGrailsPlugin("portlets")?.doWithDynamicMethods(event.ctx)
   }

    def generateTomcatContextFile() {

    }

}