rewrite system with offsets

src/commonMain/kotlin/dev/inmo/krontab/KronScheduler.kt

@@ -13,22 +13,15 @@ import dev.inmo.krontab.internal.toNearDateTime
  * @see dev.inmo.krontab.internal.CronDateTimeScheduler
  */
 interface KronScheduler {
-
     /**
      * @return Next [DateTime] when some action must be triggered according to settings of this instance
      *
      * @see dev.inmo.krontab.internal.CronDateTimeScheduler.next
      */
     suspend fun next(relatively: DateTime = DateTime.now()): DateTime?
-
-    suspend fun next(relatively: DateTimeTz): DateTimeTz?
 }
 
 suspend fun KronScheduler.nextOrRelative(relatively: DateTime = DateTime.now()): DateTime = next(relatively) ?: getAnyNext(relatively)
-suspend fun KronScheduler.nextOrRelative(relatively: DateTimeTz): DateTimeTz = next(relatively) ?: getAnyNext(relatively)
 suspend fun KronScheduler.nextOrNow(): DateTime = DateTime.now().let {
     next(it) ?: getAnyNext(it)
 }
-suspend fun KronScheduler.nextOrNowWithOffset(): DateTimeTz = DateTimeTz.nowLocal().let {
-    next(it) ?: getAnyNext(it)
-}

src/commonMain/kotlin/dev/inmo/krontab/KronSchedulerTz.kt

@@ -0,0 +1,32 @@
+package dev.inmo.krontab
+
+import com.soywiz.klock.DateTime
+import com.soywiz.klock.DateTimeTz
+
+/**
+ * This interface extending [KronScheduler] to use [DateTimeTz] with taking into account offset of incoming time for
+ * [next] operation.
+ *
+ * @see dev.inmo.krontab.internal.CronDateTimeScheduler
+ * @see dev.inmo.krontab.KronScheduler
+ */
+interface KronSchedulerTz : KronScheduler {
+    suspend fun next(relatively: DateTimeTz): DateTimeTz?
+
+    override suspend fun next(relatively: DateTime): DateTime? = next(relatively.localUnadjusted) ?.local
+}
+
+suspend fun KronSchedulerTz.nextOrRelative(relatively: DateTimeTz): DateTimeTz = next(relatively) ?: getAnyNext(
+    relatively.local
+).toOffsetUnadjusted(relatively.offset)
+suspend fun KronSchedulerTz.nextOrNowWithOffset(): DateTimeTz = DateTimeTz.nowLocal().let {
+    next(it) ?: getAnyNext(
+        it.local
+    ).toOffsetUnadjusted(it.offset)
+}
+
+suspend fun KronScheduler.next(relatively: DateTimeTz) = if (this is KronSchedulerTz) {
+    this.next(relatively)
+} else {
+    this.next(relatively.local) ?.toOffsetUnadjusted(relatively.offset)
+}

src/commonMain/kotlin/dev/inmo/krontab/KronSchedulersMerging.kt

@@ -1,8 +1,12 @@
 package dev.inmo.krontab
 
+import com.soywiz.klock.TimezoneOffset
 import dev.inmo.krontab.collection.CollectionKronScheduler
+import dev.inmo.krontab.collection.includeAll
+import dev.inmo.krontab.internal.*
 import dev.inmo.krontab.internal.CronDateTime
 import dev.inmo.krontab.internal.CronDateTimeScheduler
+import dev.inmo.krontab.internal.CronDateTimeSchedulerTz
 
 /**
  * Create new one [CollectionKronScheduler] to include all [KronScheduler]s of [this] [Iterator]
@@ -10,18 +14,23 @@ import dev.inmo.krontab.internal.CronDateTimeScheduler
  * @see CollectionKronScheduler
  * @see CollectionKronScheduler.include
  */
-fun Iterator<KronScheduler>.merge(): KronScheduler {
+fun Iterator<KronScheduler>.merge(): CollectionKronScheduler {
     val cronDateTimes = mutableListOf<CronDateTime>()
+    val timezonedCronDateTimes = mutableListOf<CronDateTimeSchedulerTz>()
     val collectionScheduler = CollectionKronScheduler()
     forEach {
         when (it) {
             is CronDateTimeScheduler -> cronDateTimes.addAll(it.cronDateTimes)
+            is CronDateTimeSchedulerTz -> timezonedCronDateTimes.add(it)
             else -> collectionScheduler.include(it)
         }
     }
     if (cronDateTimes.isNotEmpty()) {
         collectionScheduler.include(CronDateTimeScheduler(cronDateTimes))
     }
+    if (timezonedCronDateTimes.isNotEmpty()) {
+        collectionScheduler.includeAll(mergeCronDateTimeSchedulers(timezonedCronDateTimes))
+    }
     return collectionScheduler
 }
 
@@ -32,10 +41,10 @@ fun Iterator<KronScheduler>.merge(): KronScheduler {
  * @see CollectionKronScheduler.include
  */
 @Suppress("NOTHING_TO_INLINE")
-inline fun Iterable<KronScheduler>.merge(): KronScheduler = iterator().merge()
+inline fun Iterable<KronScheduler>.merge(): CollectionKronScheduler = iterator().merge()
 
 /**
  * @return Vararg shortcut for [merge]
  */
 @Suppress("NOTHING_TO_INLINE")
-inline fun merge(vararg kronDateTimeSchedulers: KronScheduler) = kronDateTimeSchedulers.iterator().merge()
+inline fun merge(vararg kronDateTimeSchedulers: KronScheduler): CollectionKronScheduler = kronDateTimeSchedulers.iterator().merge()

src/commonMain/kotlin/dev/inmo/krontab/SchedulerShortcuts.kt

@@ -11,7 +11,6 @@ internal val anyCronDateTime by lazy {
     CronDateTime()
 }
 internal fun getAnyNext(relatively: DateTime) = anyCronDateTime.toNearDateTime(relatively)!!
-internal fun getAnyNext(relatively: DateTimeTz) = anyCronDateTime.toNearDateTime(relatively)!!
 
 /**
  * [KronScheduler.next] will always return [com.soywiz.klock.DateTime.now]

src/commonMain/kotlin/dev/inmo/krontab/StringParser.kt

@@ -1,6 +1,8 @@
 package dev.inmo.krontab
 
+import com.soywiz.klock.*
 import dev.inmo.krontab.internal.*
+import dev.inmo.krontab.utils.Minutes
 
 /**
  * @see createSimpleScheduler
@@ -52,9 +54,15 @@ typealias KrontabTemplate = String
  * * "1 2 3 F,4,L 5 2021" for triggering in near first second of second minute of third hour of fourth day of may of 2021st year
  * * "1 2 3 F,4,L 5 2021 60o" for triggering in near first second of second minute of third hour of fourth day of may of 2021st year with timezone UTC+01:00
  *
+ * @return In case when offset parameter is absent in [incoming] will be used [createSimpleScheduler] method and
+ * returned [CronDateTimeScheduler]. In case when offset parameter there is in [incoming] [KrontabTemplate] will be used
+ * [createKronSchedulerWithOffset] and returned [CronDateTimeSchedulerTz]
+ *
  * @see dev.inmo.krontab.internal.createKronScheduler
  */
-fun createSimpleScheduler(incoming: KrontabTemplate): KronScheduler {
+fun createSimpleScheduler(
+    incoming: KrontabTemplate
+): KronScheduler {
     var offsetParsed: Int? = null
     var yearParsed: Array<Int>? = null
     val (secondsSource, minutesSource, hoursSource, dayOfMonthSource, monthSource) = incoming.split(" ").also {
@@ -81,22 +89,53 @@ fun createSimpleScheduler(incoming: KrontabTemplate): KronScheduler {
     val dayOfMonthParsed = parseDaysOfMonth(dayOfMonthSource)
     val monthParsed = parseMonths(monthSource)
 
-    return createKronScheduler(
-        secondsParsed, minutesParsed, hoursParsed, dayOfMonthParsed, monthParsed, yearParsed, offsetParsed
+    return offsetParsed ?.let { offset ->
+        createKronSchedulerWithOffset(
+            secondsParsed, minutesParsed, hoursParsed, dayOfMonthParsed, monthParsed, yearParsed, TimezoneOffset(offset.minutes)
+        )
+    } ?: createKronScheduler(
+        secondsParsed, minutesParsed, hoursParsed, dayOfMonthParsed, monthParsed, yearParsed
     )
 }
 
+fun createSimpleScheduler(
+    incoming: KrontabTemplate,
+    defaultOffset: Minutes
+): KronSchedulerTz {
+    val scheduler = createSimpleScheduler(incoming)
+    return if (scheduler is KronSchedulerTz) {
+        scheduler
+    } else {
+        CronDateTimeSchedulerTz(
+            (scheduler as CronDateTimeScheduler).cronDateTimes,
+            TimezoneOffset(defaultOffset.minutes)
+        )
+    }
+}
+
 /**
  * Shortcut for [createSimpleScheduler]
  */
 fun buildSchedule(incoming: KrontabTemplate): KronScheduler = createSimpleScheduler(incoming)
+/**
+ * Shortcut for [createSimpleScheduler]
+ */
+fun buildSchedule(incoming: KrontabTemplate, defaultOffset: Minutes): KronSchedulerTz = createSimpleScheduler(incoming, defaultOffset)
 
 /**
  * Shortcut for [buildSchedule]
  */
 fun KrontabTemplate.toSchedule(): KronScheduler = buildSchedule(this)
+/**
+ * Shortcut for [buildSchedule]
+ */
+fun KrontabTemplate.toSchedule(defaultOffset: Minutes): KronSchedulerTz = buildSchedule(this, defaultOffset)
 
 /**
  * Shortcut for [buildSchedule]
  */
-fun KrontabTemplate.toKronScheduler(): KronScheduler = buildSchedule(this)
+fun KrontabTemplate.toKronScheduler(): KronScheduler = buildSchedule(this)
+/**
+ * Shortcut for [buildSchedule]
+ */
+fun KrontabTemplate.toKronScheduler(defaultOffset: Minutes): KronSchedulerTz = buildSchedule(this, defaultOffset)

src/commonMain/kotlin/dev/inmo/krontab/builder/SchedulerBuilder.kt

@@ -1,9 +1,10 @@
 package dev.inmo.krontab.builder
 
-import com.soywiz.klock.TimeSpan
-import com.soywiz.klock.TimezoneOffset
+import com.soywiz.klock.*
 import dev.inmo.krontab.KronScheduler
+import dev.inmo.krontab.KronSchedulerTz
 import dev.inmo.krontab.internal.createKronScheduler
+import dev.inmo.krontab.internal.createKronSchedulerWithOffset
 import dev.inmo.krontab.utils.Minutes
 
 /**
@@ -19,6 +20,22 @@ fun buildSchedule(settingsBlock: SchedulerBuilder.() -> Unit): KronScheduler {
     return builder.build()
 }
 
+/**
+ * Will help to create an instance of [KronScheduler]
+ *
+ * @see dev.inmo.krontab.createSimpleScheduler
+ */
+fun buildSchedule(
+    offset: Minutes,
+    settingsBlock: SchedulerBuilder.() -> Unit
+): KronSchedulerTz {
+    val builder = SchedulerBuilder(offset = offset)
+
+    builder.settingsBlock()
+
+    return builder.build() as KronSchedulerTz
+}
+
 class SchedulerBuilder(
     private var seconds: Array<Byte>? = null,
     private var minutes: Array<Byte>? = null,
@@ -26,7 +43,7 @@ class SchedulerBuilder(
     private var dayOfMonth: Array<Byte>? = null,
     private var month: Array<Byte>? = null,
     private var year: Array<Int>? = null,
-    var offset: Minutes? = null
+    private val offset: Minutes? = null
 ) {
     private fun <I, T : TimeBuilder<I>> callAndReturn(
         initial: Array<I>?,
@@ -110,32 +127,13 @@ class SchedulerBuilder(
         ) ?.toTypedArray()
     }
 
-    /**
-     * Setter of [offset] property
-     */
-    fun offset(offset: Minutes?) {
-        this.offset = offset
-    }
-
-    /**
-     * Setter of [offset] property
-     */
-    fun offset(offset: TimeSpan?) {
-        this.offset = offset ?.minutes ?.toInt()
-    }
-
-    /**
-     * Setter of [offset] property
-     */
-    fun offset(offset: TimezoneOffset?) {
-        this.offset = offset ?.totalMinutesInt
-    }
-
     /**
      * @return Completely built and independent [KronScheduler]
      *
      * @see dev.inmo.krontab.createSimpleScheduler
      * @see dev.inmo.krontab.internal.createKronScheduler
      */
-    fun build(): KronScheduler = createKronScheduler(seconds, minutes, hours, dayOfMonth, month, year)
+    fun build(): KronScheduler = offset ?.let {
+        createKronSchedulerWithOffset(seconds, minutes, hours, dayOfMonth, month, year, TimezoneOffset(it.minutes))
+    } ?: createKronScheduler(seconds, minutes, hours, dayOfMonth, month, year)
 }

src/commonMain/kotlin/dev/inmo/krontab/collection/CollectionKronScheduler.kt

@@ -12,7 +12,7 @@ import dev.inmo.krontab.internal.toNearDateTime
  */
 data class CollectionKronScheduler internal constructor(
     internal val schedulers: MutableList<KronScheduler>
-) : KronScheduler {
+) : KronSchedulerTz {
     internal constructor() : this(mutableListOf())
 
     /**
@@ -51,6 +51,6 @@ data class CollectionKronScheduler internal constructor(
     }
 
     override suspend fun next(relatively: DateTimeTz): DateTimeTz {
-        return schedulers.mapNotNull { it.next(relatively) }.minOrNull() ?: getAnyNext(relatively)
+        return schedulers.mapNotNull { it.next(relatively) }.minOrNull() ?: getAnyNext(relatively.local).toOffsetUnadjusted(relatively.offset)
     }
 }

src/commonMain/kotlin/dev/inmo/krontab/internal/CronDateTime.kt

@@ -12,7 +12,6 @@ import dev.inmo.krontab.utils.Minutes
  * @param seconds 0-59
  */
 internal data class CronDateTime(
-    val offset: Int? = null,
     val year: Int? = null,
     val month: Byte? = null,
     val dayOfMonth: Byte? = null,
@@ -30,7 +29,6 @@ internal data class CronDateTime(
     }
 
     internal val klockDayOfMonth = dayOfMonth ?.plus(1)
-    internal val klockOffset = offset ?.minutes ?.offset
 }
 
 /**
@@ -82,35 +80,14 @@ internal fun CronDateTime.toNearDateTime(relativelyTo: DateTime = DateTime.now()
     return current
 }
 
-/**
- * THIS METHOD WILL TAKE CARE ABOUT [offset] PARAMETER. It was decided due to the fact that we unable to get
- * real timezone offset from simple [DateTime]
- *
- * @return The near [DateTime] which happens after [relativelyTo] or will be equal to [relativelyTo]
- */
-internal fun CronDateTime.toNearDateTime(
-    relativelyTo: DateTimeTz
-): DateTimeTz? {
-    val klockOffset = klockOffset
-    return if (klockOffset != null) {
-        toNearDateTime(relativelyTo.toOffset(klockOffset).local) ?.toOffsetUnadjusted(klockOffset) ?.toOffset(relativelyTo.offset)
-    } else {
-        toNearDateTime(relativelyTo.local) ?.toOffsetUnadjusted(relativelyTo.offset)
-    }
-}
-
-/**
- * @return [KronScheduler] (in fact [CronDateTimeScheduler]) based on incoming data
- */
-internal fun createKronScheduler(
+internal fun createCronDateTimeList(
     seconds: Array<Byte>? = null,
     minutes: Array<Byte>? = null,
     hours: Array<Byte>? = null,
     dayOfMonth: Array<Byte>? = null,
     month: Array<Byte>? = null,
-    years: Array<Int>? = null,
-    offset: Minutes? = null
-): KronScheduler {
+    years: Array<Int>? = null
+): List<CronDateTime> {
     val resultCronDateTimes = mutableListOf(CronDateTime())
 
     seconds ?.fillWith(resultCronDateTimes) { previousCronDateTime: CronDateTime, currentTime: Byte ->
@@ -141,9 +118,29 @@ internal fun createKronScheduler(
         previousCronDateTime.copy(year = currentTime)
     }
 
-    offset ?.fillWith(resultCronDateTimes) { previousCronDateTime: CronDateTime, currentTime: Int ->
-        previousCronDateTime.copy(year = currentTime)
-    }
-
-    return CronDateTimeScheduler(resultCronDateTimes.toList())
+    return resultCronDateTimes.toList()
 }
+
+/**
+ * @return [KronScheduler] (in fact [CronDateTimeScheduler]) based on incoming data
+ */
+internal fun createKronScheduler(
+    seconds: Array<Byte>? = null,
+    minutes: Array<Byte>? = null,
+    hours: Array<Byte>? = null,
+    dayOfMonth: Array<Byte>? = null,
+    month: Array<Byte>? = null,
+    years: Array<Int>? = null
+): KronScheduler = CronDateTimeScheduler(createCronDateTimeList(seconds, minutes, hours, dayOfMonth, month, years))
+/**
+ * @return [KronScheduler] (in fact [CronDateTimeScheduler]) based on incoming data
+ */
+internal fun createKronSchedulerWithOffset(
+    seconds: Array<Byte>? = null,
+    minutes: Array<Byte>? = null,
+    hours: Array<Byte>? = null,
+    dayOfMonth: Array<Byte>? = null,
+    month: Array<Byte>? = null,
+    years: Array<Int>? = null,
+    offset: TimezoneOffset
+): KronScheduler = CronDateTimeSchedulerTz(createCronDateTimeList(seconds, minutes, hours, dayOfMonth, month, years), offset)

src/commonMain/kotlin/dev/inmo/krontab/internal/CronDateTimeScheduler.kt

@@ -1,7 +1,6 @@
 package dev.inmo.krontab.internal
 
-import com.soywiz.klock.DateTime
-import com.soywiz.klock.DateTimeTz
+import com.soywiz.klock.*
 import dev.inmo.krontab.*
 import dev.inmo.krontab.collection.plus
 
@@ -30,10 +29,6 @@ internal data class CronDateTimeScheduler internal constructor(
     override suspend fun next(relatively: DateTime): DateTime {
         return cronDateTimes.mapNotNull { it.toNearDateTime(relatively) }.minOrNull() ?: getAnyNext(relatively)
     }
-
-    override suspend fun next(relatively: DateTimeTz): DateTimeTz {
-        return cronDateTimes.mapNotNull { it.toNearDateTime(relatively) }.minOrNull() ?: getAnyNext(relatively)
-    }
 }
 
 internal fun mergeCronDateTimeSchedulers(schedulers: List<CronDateTimeScheduler>) = CronDateTimeScheduler(

src/commonMain/kotlin/dev/inmo/krontab/internal/CronDateTimeSchedulerTz.kt

@@ -0,0 +1,30 @@
+package dev.inmo.krontab.internal
+
+import com.soywiz.klock.*
+import dev.inmo.krontab.*
+import dev.inmo.krontab.collection.plus
+
+/**
+ * Cron-oriented realisation of [KronScheduler] with taking into account [offset] for list of [cronDateTimes]
+ *
+ * @see CronDateTime
+ */
+internal data class CronDateTimeSchedulerTz internal constructor(
+    internal val cronDateTimes: List<CronDateTime>,
+    internal val offset: TimezoneOffset
+) : KronSchedulerTz {
+    override suspend fun next(relatively: DateTimeTz): DateTimeTz? {
+        val dateTimeWithActualOffset = relatively.utc.toOffset(offset).local
+        return cronDateTimes.mapNotNull {
+            it.toNearDateTime(dateTimeWithActualOffset)
+        }.minOrNull() ?.toOffset(relatively.offset)
+    }
+}
+
+internal fun mergeCronDateTimeSchedulers(
+    schedulers: List<CronDateTimeSchedulerTz>
+) = schedulers.groupBy {
+    it.offset
+}.map { (offset, schedulers) ->
+    CronDateTimeSchedulerTz(schedulers.flatMap { it.cronDateTimes }, offset)
+}

src/commonMain/kotlin/dev/inmo/krontab/internal/Ranges.kt

@@ -6,8 +6,3 @@ internal val dayOfMonthRange = 0 .. 30
 internal val hoursRange = 0 .. 23
 internal val minutesRange = 0 .. 59
 internal val secondsRange = minutesRange
-
-/**
- * From 0 - 1439 minutes (1440 == 24 hours, that is the same as 0 in terms of timezones)
- */
-internal val offsetRange = 0 until (hoursRange.count() * minutesRange.count())

src/commonTest/kotlin/dev/inmo/krontab/utils/StringParseTest.kt

@@ -1,6 +1,7 @@
 package dev.inmo.krontab.utils
 
 import com.soywiz.klock.DateTimeTz
+import dev.inmo.krontab.KronSchedulerTz
 import dev.inmo.krontab.buildSchedule
 import dev.inmo.krontab.internal.offsetRange
 import kotlinx.coroutines.*
@@ -84,9 +85,8 @@ class StringParseTest {
 
         runTest {
             for (i in offsetRange) {
-                val kronScheduler = buildSchedule("* * 10 * * ${i}o")
+                val kronScheduler = buildSchedule("* * 10 * * ${i}o") as KronSchedulerTz
                 val next = kronScheduler.next(now)
-
             }
         }
     }

src/commonTest/kotlin/dev/inmo/krontab/utils/TimeZoneTest.kt

@@ -2,6 +2,7 @@ package dev.inmo.krontab.utils
 
 import com.soywiz.klock.*
 import dev.inmo.krontab.builder.buildSchedule
+import dev.inmo.krontab.next
 import kotlin.test.Test
 import kotlin.test.assertEquals