diff --git a/.DS_Store b/.DS_Store
new file mode 100644
index 0000000..5008ddf
Binary files /dev/null and b/.DS_Store differ
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..64fc127
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,94 @@
+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio and WebStorm
+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+
+# User-specific stuff
+.idea/**/workspace.xml
+.idea/**/tasks.xml
+.idea/**/usage.statistics.xml
+.idea/**/dictionaries
+.idea/**/shelf
+
+# Generated files
+.idea/**/contentModel.xml
+
+# Sensitive or high-churn files
+.idea/**/dataSources/
+.idea/**/dataSources.ids
+.idea/**/dataSources.local.xml
+.idea/**/sqlDataSources.xml
+.idea/**/dynamic.xml
+.idea/**/uiDesigner.xml
+.idea/**/dbnavigator.xml
+
+# Gradle
+.idea/**/gradle.xml
+.idea/**/libraries
+
+# Gradle and Maven with auto-import
+# When using Gradle or Maven with auto-import, you should exclude module files,
+# since they will be recreated, and may cause churn. Uncomment if using
+# auto-import.
+# .idea/modules.xml
+# .idea/*.iml
+# .idea/modules
+# *.iml
+# *.ipr
+
+# CMake
+cmake-build-*/
+
+# Mongo Explorer plugin
+.idea/**/mongoSettings.xml
+
+# File-based project format
+*.iws
+
+# IntelliJ
+out/
+
+# mpeltonen/sbt-idea plugin
+.idea_modules/
+
+# JIRA plugin
+atlassian-ide-plugin.xml
+
+# Cursive Clojure plugin
+.idea/replstate.xml
+
+# Crashlytics plugin (for Android Studio and IntelliJ)
+com_crashlytics_export_strings.xml
+crashlytics.properties
+crashlytics-build.properties
+fabric.properties
+
+# Editor-based Rest Client
+.idea/httpRequests
+
+# Android studio 3.1+ serialized cache file
+.idea/caches/build_file_checksums.ser
+
+# Compiled class file
+*.class
+
+# Log file
+*.log
+
+# BlueJ files
+*.ctxt
+
+# Mobile Tools for Java (J2ME)
+.mtj.tmp/
+
+# Package Files #
+*.jar
+*.war
+*.nar
+*.ear
+*.zip
+*.tar.gz
+*.rar
+
+# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
+hs_err_pid*
+
+build/
diff --git a/.gradle/5.2.1/executionHistory/executionHistory.bin b/.gradle/5.2.1/executionHistory/executionHistory.bin
new file mode 100644
index 0000000..9906db4
Binary files /dev/null and b/.gradle/5.2.1/executionHistory/executionHistory.bin differ
diff --git a/.gradle/5.2.1/executionHistory/executionHistory.lock b/.gradle/5.2.1/executionHistory/executionHistory.lock
new file mode 100644
index 0000000..cf22416
Binary files /dev/null and b/.gradle/5.2.1/executionHistory/executionHistory.lock differ
diff --git a/.gradle/5.2.1/fileChanges/last-build.bin b/.gradle/5.2.1/fileChanges/last-build.bin
new file mode 100644
index 0000000..f76dd23
Binary files /dev/null and b/.gradle/5.2.1/fileChanges/last-build.bin differ
diff --git a/.gradle/5.2.1/fileContent/fileContent.lock b/.gradle/5.2.1/fileContent/fileContent.lock
new file mode 100644
index 0000000..1c4952b
Binary files /dev/null and b/.gradle/5.2.1/fileContent/fileContent.lock differ
diff --git a/.gradle/5.2.1/fileHashes/fileHashes.bin b/.gradle/5.2.1/fileHashes/fileHashes.bin
new file mode 100644
index 0000000..ae75014
Binary files /dev/null and b/.gradle/5.2.1/fileHashes/fileHashes.bin differ
diff --git a/.gradle/5.2.1/fileHashes/fileHashes.lock b/.gradle/5.2.1/fileHashes/fileHashes.lock
new file mode 100644
index 0000000..91ece94
Binary files /dev/null and b/.gradle/5.2.1/fileHashes/fileHashes.lock differ
diff --git a/.gradle/5.2.1/gc.properties b/.gradle/5.2.1/gc.properties
new file mode 100644
index 0000000..e69de29
diff --git a/.gradle/buildOutputCleanup/buildOutputCleanup.lock b/.gradle/buildOutputCleanup/buildOutputCleanup.lock
new file mode 100644
index 0000000..949c6d6
Binary files /dev/null and b/.gradle/buildOutputCleanup/buildOutputCleanup.lock differ
diff --git a/.gradle/buildOutputCleanup/cache.properties b/.gradle/buildOutputCleanup/cache.properties
new file mode 100644
index 0000000..4f0c09f
--- /dev/null
+++ b/.gradle/buildOutputCleanup/cache.properties
@@ -0,0 +1,2 @@
+#Mon Aug 05 11:06:56 CEST 2019
+gradle.version=5.2.1
diff --git a/.gradle/buildOutputCleanup/outputFiles.bin b/.gradle/buildOutputCleanup/outputFiles.bin
new file mode 100644
index 0000000..fa9d5e3
Binary files /dev/null and b/.gradle/buildOutputCleanup/outputFiles.bin differ
diff --git a/.gradle/vcs-1/gc.properties b/.gradle/vcs-1/gc.properties
new file mode 100644
index 0000000..e69de29
diff --git a/.idea/$PRODUCT_WORKSPACE_FILE$ b/.idea/$PRODUCT_WORKSPACE_FILE$
new file mode 100644
index 0000000..3733e0d
--- /dev/null
+++ b/.idea/$PRODUCT_WORKSPACE_FILE$
@@ -0,0 +1,19 @@
+
+
+
+
+
+
+ 1.8
+
+
+
+
+
+
+
+
\ No newline at end of file
diff --git a/.idea/.name b/.idea/.name
new file mode 100644
index 0000000..64f7f1b
--- /dev/null
+++ b/.idea/.name
@@ -0,0 +1 @@
+untitled
\ No newline at end of file
diff --git a/.idea/codeStyles/Project.xml b/.idea/codeStyles/Project.xml
new file mode 100644
index 0000000..1bec35e
--- /dev/null
+++ b/.idea/codeStyles/Project.xml
@@ -0,0 +1,10 @@
+
+
+
+
+
+
+
+
+
+
\ No newline at end of file
diff --git a/.idea/codeStyles/codeStyleConfig.xml b/.idea/codeStyles/codeStyleConfig.xml
new file mode 100644
index 0000000..79ee123
--- /dev/null
+++ b/.idea/codeStyles/codeStyleConfig.xml
@@ -0,0 +1,5 @@
+
+
+
+
+
\ No newline at end of file
diff --git a/.idea/compiler.xml b/.idea/compiler.xml
new file mode 100644
index 0000000..1d7cb70
--- /dev/null
+++ b/.idea/compiler.xml
@@ -0,0 +1,9 @@
+
+
+
+
+
+
+
+
+
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
new file mode 100644
index 0000000..bc8d0a3
--- /dev/null
+++ b/.idea/misc.xml
@@ -0,0 +1,7 @@
+
+
+
+
+
+
+
\ No newline at end of file
diff --git a/build.gradle b/build.gradle
new file mode 100644
index 0000000..665f54e
--- /dev/null
+++ b/build.gradle
@@ -0,0 +1,25 @@
+plugins {
+ id 'java'
+ id 'org.jetbrains.kotlin.jvm' version '1.3.41'
+}
+
+group 'com.philjay.rrule'
+version '1.0.0'
+
+sourceCompatibility = 1.8
+
+repositories {
+ mavenCentral()
+}
+
+dependencies {
+ implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
+ testCompile group: 'junit', name: 'junit', version: '4.12'
+}
+
+compileKotlin {
+ kotlinOptions.jvmTarget = "1.8"
+}
+compileTestKotlin {
+ kotlinOptions.jvmTarget = "1.8"
+}
\ No newline at end of file
diff --git a/gradle.properties b/gradle.properties
new file mode 100644
index 0000000..29e08e8
--- /dev/null
+++ b/gradle.properties
@@ -0,0 +1 @@
+kotlin.code.style=official
\ No newline at end of file
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 0000000..2b94657
--- /dev/null
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,6 @@
+#Mon Aug 05 11:07:13 CEST 2019
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.2.1-all.zip
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+zipStorePath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME
diff --git a/gradlew b/gradlew
new file mode 100755
index 0000000..af6708f
--- /dev/null
+++ b/gradlew
@@ -0,0 +1,172 @@
+#!/usr/bin/env sh
+
+##############################################################################
+##
+## Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+ ls=`ls -ld "$PRG"`
+ link=`expr "$ls" : '.*-> \(.*\)$'`
+ if expr "$link" : '/.*' > /dev/null; then
+ PRG="$link"
+ else
+ PRG=`dirname "$PRG"`"/$link"
+ fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+ echo "$*"
+}
+
+die () {
+ echo
+ echo "$*"
+ echo
+ exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+ CYGWIN* )
+ cygwin=true
+ ;;
+ Darwin* )
+ darwin=true
+ ;;
+ MINGW* )
+ msys=true
+ ;;
+ NONSTOP* )
+ nonstop=true
+ ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+ if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+ # IBM's JDK on AIX uses strange locations for the executables
+ JAVACMD="$JAVA_HOME/jre/sh/java"
+ else
+ JAVACMD="$JAVA_HOME/bin/java"
+ fi
+ if [ ! -x "$JAVACMD" ] ; then
+ die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+ fi
+else
+ JAVACMD="java"
+ which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+ MAX_FD_LIMIT=`ulimit -H -n`
+ if [ $? -eq 0 ] ; then
+ if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+ MAX_FD="$MAX_FD_LIMIT"
+ fi
+ ulimit -n $MAX_FD
+ if [ $? -ne 0 ] ; then
+ warn "Could not set maximum file descriptor limit: $MAX_FD"
+ fi
+ else
+ warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+ fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+ GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin ; then
+ APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+ CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+ JAVACMD=`cygpath --unix "$JAVACMD"`
+
+ # We build the pattern for arguments to be converted via cygpath
+ ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+ SEP=""
+ for dir in $ROOTDIRSRAW ; do
+ ROOTDIRS="$ROOTDIRS$SEP$dir"
+ SEP="|"
+ done
+ OURCYGPATTERN="(^($ROOTDIRS))"
+ # Add a user-defined pattern to the cygpath arguments
+ if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+ OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+ fi
+ # Now convert the arguments - kludge to limit ourselves to /bin/sh
+ i=0
+ for arg in "$@" ; do
+ CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+ CHECK2=`echo "$arg"|egrep -c "^-"` ### Determine if an option
+
+ if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then ### Added a condition
+ eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+ else
+ eval `echo args$i`="\"$arg\""
+ fi
+ i=$((i+1))
+ done
+ case $i in
+ (0) set -- ;;
+ (1) set -- "$args0" ;;
+ (2) set -- "$args0" "$args1" ;;
+ (3) set -- "$args0" "$args1" "$args2" ;;
+ (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+ (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+ (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+ (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+ (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+ (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+ esac
+fi
+
+# Escape application args
+save () {
+ for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+ echo " "
+}
+APP_ARGS=$(save "$@")
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
+if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then
+ cd "$(dirname "$0")"
+fi
+
+exec "$JAVACMD" "$@"
diff --git a/gradlew.bat b/gradlew.bat
new file mode 100644
index 0000000..0f8d593
--- /dev/null
+++ b/gradlew.bat
@@ -0,0 +1,84 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/settings.gradle b/settings.gradle
new file mode 100644
index 0000000..00221b6
--- /dev/null
+++ b/settings.gradle
@@ -0,0 +1,2 @@
+rootProject.name = 'rrule'
+
diff --git a/src/main/kotlin/com/philjay/Frequency.kt b/src/main/kotlin/com/philjay/Frequency.kt
new file mode 100644
index 0000000..cf65e69
--- /dev/null
+++ b/src/main/kotlin/com/philjay/Frequency.kt
@@ -0,0 +1,17 @@
+package com.philjay
+
+
+enum class Frequency {
+ Daily, Weekly, Monthly, Yearly;
+
+ override fun toString(): String {
+ return super.toString().toUpperCase()
+ }
+
+ companion object {
+
+ val values by lazy {
+ values()
+ }
+ }
+}
\ No newline at end of file
diff --git a/src/main/kotlin/com/philjay/RRule.kt b/src/main/kotlin/com/philjay/RRule.kt
new file mode 100644
index 0000000..af264a5
--- /dev/null
+++ b/src/main/kotlin/com/philjay/RRule.kt
@@ -0,0 +1,218 @@
+package com.philjay
+
+import java.time.Instant
+import java.time.LocalDateTime
+import java.time.ZoneOffset
+import java.time.format.DateTimeFormatter
+
+open class RRule() {
+
+ private val name = "RRULE"
+
+ var freq: Frequency = Frequency.Daily
+ protected set
+ var wkst: Weekday? = null
+ protected set
+ var until: Instant? = null
+ protected set
+ var count = 0
+ protected set
+ var interval = 0
+ protected set
+
+ val byDay = arrayListOf()
+ val byMonth = arrayListOf() // in +/-[1-12]
+ val byMonthDay = arrayListOf() // in +/-[1-31]
+ val byWeekNo = arrayListOf() // in +/-[1-53]
+ val byYearDay = arrayListOf() // in +/-[1-366]
+ val bySetPos = arrayListOf() // in +/-[1-366]
+
+ constructor(rfc2445String: String) : this() {
+ val components = rfc2445String.replace("$name:", "").split(";", "=")
+ var i = 0
+ while (i < components.size) {
+ val component = components[i]
+ if (component == "FREQ") {
+ i += 1
+ freq = when (components[i]) {
+ "DAILY" -> Frequency.Daily
+ "WEEKLY" -> Frequency.Weekly
+ "MONTHLY" -> Frequency.Monthly
+ "YEARLY" -> Frequency.Yearly
+ else -> Frequency.Daily
+ }
+ }
+ if (component == "INTERVAL") {
+ i += 1
+ interval = components[i].toIntOrNull() ?: 1
+ }
+ if (component == "BYDAY") {
+ i += 1
+ val dayStrings = components[i].split(",")
+ for (dayString in dayStrings) {
+ val weekDay = weekDayFromString(dayString)
+
+ if (weekDay != null) {
+ if (dayString.length > 2) {
+ val number = dayString.replace(Regex("[^-?0-9]+"), "").toIntOrNull() ?: 0
+ byDay.add(WeekdayNum(number, weekDay))
+ } else {
+ byDay.add(WeekdayNum(0, weekDay))
+ }
+ }
+ }
+ }
+
+ if (component == "BYMONTHDAY") {
+ i += 1
+ val dayStrings = components[i].split(",")
+ for (dayString in dayStrings) {
+ val monthDay = dayString.toIntOrNull()
+ if (monthDay != null) {
+ byMonthDay.add(monthDay)
+ }
+ }
+ }
+
+ if (component == "BYMONTH") {
+ i += 1
+ val monthStrings = components[i].split(",")
+ for (monthString in monthStrings) {
+ val month = monthString.toIntOrNull()
+ if (month != null) {
+ byMonth.add(month)
+ }
+ }
+ }
+
+ if (component == "BYWEEKNO") {
+ i += 1
+ val weekStrings = components[i].split(",")
+ for (weekString in weekStrings) {
+ val week = weekString.toIntOrNull()
+ if (week != null) {
+ byWeekNo.add(week)
+ }
+ }
+ }
+
+ if (component == "BYYEARDAY") {
+ i += 1
+ val dayStrings = components[i].split(",")
+ for (dayString in dayStrings) {
+ val yearDay = dayString.toIntOrNull()
+ if (yearDay != null) {
+ byYearDay.add(yearDay)
+ }
+ }
+ }
+
+ if (component == "BYSETPOS") {
+ i += 1
+ val posStrings = components[i].split(",")
+ for (posString in posStrings) {
+ val pos = posString.toIntOrNull()
+ if (pos != null) {
+ bySetPos.add(pos)
+ }
+ }
+ }
+
+ if (component == "COUNT") {
+ i += 1
+ count = components[i].toIntOrNull() ?: 1
+ } else if (component == "UNTIL") {
+ i += 1
+ until = LocalDateTime.parse(components[i], dateFormatter).toInstant(ZoneOffset.UTC)
+ }
+
+ if (component == "WKST") {
+ i += 1
+ wkst = weekDayFromString(components[i])
+ }
+ i++
+ }
+ }
+
+ /**
+ * Transforms this RRule to a RFC2445 standard iCal String.
+ */
+ fun toRFC2445String(): String {
+
+ val buf = StringBuilder()
+ buf.append("$name:")
+ buf.append("FREQ=").append(freq.toString())
+ if (interval > 0) {
+ buf.append(";INTERVAL=").append(interval)
+ }
+ if (until != null) {
+ buf.append(";UNTIL=").append(dateFormatter.format(until))
+ }
+ if (count > 0) {
+ buf.append(";COUNT=").append(count)
+ }
+ if (byYearDay.isNotEmpty()) {
+ buf.append(";BYYEARDAY=")
+ writeIntList(byYearDay, buf)
+ }
+ if (byMonth.isNotEmpty()) {
+ buf.append(";BYMONTH=")
+ writeIntList(byMonth, buf)
+ }
+ if (byMonthDay.isNotEmpty()) {
+ buf.append(";BYMONTHDAY=")
+ writeIntList(byMonthDay, buf)
+ }
+ if (byWeekNo.isNotEmpty()) {
+ buf.append(";BYWEEKNO=")
+ writeIntList(byWeekNo, buf)
+ }
+ if (byDay.isNotEmpty()) {
+ buf.append(";BYDAY=")
+ var first = true
+ for (day in byDay) {
+ if (!first) {
+ buf.append(',')
+ } else {
+ first = false
+ }
+ buf.append(day.toICalString())
+ }
+ }
+ if (bySetPos.isNotEmpty()) {
+ buf.append(";BYSETPOS=")
+ writeIntList(bySetPos, buf)
+ }
+ if (wkst != null) {
+ buf.append(";WKST=").append(wkst?.initials)
+ }
+
+ return buf.toString()
+ }
+
+ private fun writeIntList(integers: List, out: StringBuilder) {
+ for (i in integers.indices) {
+ if (0 != i) {
+ out.append(',')
+ }
+ out.append(integers[i])
+ }
+ }
+
+ private fun weekDayFromString(dayString: String): Weekday? {
+ return when {
+ dayString.contains("SU") -> Weekday.Sunday
+ dayString.contains("MO") -> Weekday.Monday
+ dayString.contains("TU") -> Weekday.Tuesday
+ dayString.contains("WE") -> Weekday.Wednesday
+ dayString.contains("TH") -> Weekday.Thursday
+ dayString.contains("FR") -> Weekday.Friday
+ dayString.contains("SA") -> Weekday.Saturday
+ else -> null
+ }
+ }
+
+ companion object {
+ private val dateFormatter = DateTimeFormatter.ofPattern("yyyyMMdd'T'HHmmss'Z'").withZone(ZoneOffset.UTC)
+ }
+}
\ No newline at end of file
diff --git a/src/main/kotlin/com/philjay/Weekday.kt b/src/main/kotlin/com/philjay/Weekday.kt
new file mode 100644
index 0000000..934d962
--- /dev/null
+++ b/src/main/kotlin/com/philjay/Weekday.kt
@@ -0,0 +1,33 @@
+package com.philjay
+
+enum class Weekday(val initials: String) {
+ Monday("MO"), Tuesday("TU"), Wednesday("WE"), Thursday("TH"), Friday("FR"), Saturday("SA"), Sunday("SU");
+
+ companion object {
+
+ val values by lazy {
+ values()
+ }
+
+ fun fromString(string: String?): Weekday? {
+ return if (string.isNullOrEmpty() || string.length < 2) {
+ null
+ } else {
+ try {
+ string.toLowerCase()
+ string[0].toUpperCase()
+ valueOf(string)
+ } catch (e: Exception) {
+ val dayInitials = string.substring(0, 2)
+
+ for (value in values) {
+ if (value.initials.equals(dayInitials, true)) {
+ return value
+ }
+ }
+ null
+ }
+ }
+ }
+ }
+}
\ No newline at end of file
diff --git a/src/main/kotlin/com/philjay/WeekdayNum.kt b/src/main/kotlin/com/philjay/WeekdayNum.kt
new file mode 100644
index 0000000..6df0e79
--- /dev/null
+++ b/src/main/kotlin/com/philjay/WeekdayNum.kt
@@ -0,0 +1,14 @@
+package com.philjay
+
+data class WeekdayNum(
+ val number: Int, // -53 - +53
+ val weekday: Weekday
+) {
+
+ fun toICalString(): String {
+ return if (number != 0)
+ "$number" + weekday.initials
+ else
+ weekday.initials
+ }
+}
\ No newline at end of file
diff --git a/src/test/kotlin/RRuleTest.kt b/src/test/kotlin/RRuleTest.kt
new file mode 100644
index 0000000..614a514
--- /dev/null
+++ b/src/test/kotlin/RRuleTest.kt
@@ -0,0 +1,45 @@
+import com.philjay.RRule
+import com.philjay.Weekday
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNull
+import org.junit.Test
+
+class RRuleTest {
+
+ private val ruleStrings = listOf(
+ "RRULE:FREQ=DAILY;INTERVAL=1",
+ "RRULE:FREQ=WEEKLY;INTERVAL=2",
+ "RRULE:FREQ=MONTHLY;INTERVAL=3",
+ "RRULE:FREQ=YEARLY;INTERVAL=4",
+ "RRULE:FREQ=WEEKLY;INTERVAL=2;BYDAY=FR;WKST=SU",
+ "RRULE:FREQ=WEEKLY;INTERVAL=1;BYDAY=FR,SU",
+ "RRULE:FREQ=DAILY;INTERVAL=1;UNTIL=20201009T220000Z",
+ "RRULE:FREQ=DAILY;INTERVAL=10;COUNT=5",
+ "RRULE:FREQ=MONTHLY;INTERVAL=2;COUNT=5;BYDAY=2FR",
+ "RRULE:FREQ=MONTHLY;INTERVAL=2;COUNT=10;BYDAY=1SU,-1SU",
+ "RRULE:FREQ=MONTHLY;INTERVAL=1;COUNT=4;BYMONTHDAY=10,11,15",
+ "RRULE:FREQ=YEARLY;INTERVAL=2;COUNT=10;BYMONTH=2,6"
+ )
+
+ @Test
+ fun testRRule() {
+
+ for (ruleString in ruleStrings) {
+ val rule = RRule(ruleString)
+ assertEquals(ruleString, rule.toRFC2445String())
+ }
+ }
+
+ @Test
+ fun testWeekdayFromString() {
+
+ assertEquals(Weekday.Sunday, Weekday.fromString("Sunday"))
+ assertEquals(Weekday.Monday, Weekday.fromString("mo"))
+ assertEquals(Weekday.Thursday, Weekday.fromString("th"))
+ assertEquals(Weekday.Friday, Weekday.fromString("FRIDAY"))
+ assertEquals(Weekday.Wednesday, Weekday.fromString("wednesday"))
+ assertNull(Weekday.fromString(""))
+ assertNull(Weekday.fromString(null))
+ assertNull(Weekday.fromString("s"))
+ }
+}
\ No newline at end of file