add ScheduleBuilder as the variant of DSL

src/commonMain/kotlin/com/github/insanusmokrassar/krontab/builder/SchedulerBuilder.kt

@@ -0,0 +1,109 @@
+package com.github.insanusmokrassar.krontab.builder
+
+import com.github.insanusmokrassar.krontab.*
+
+fun buildSchedule(settingsBlock: SchedulerBuilder.() -> Unit): CronDateTimeScheduler {
+    val builder = SchedulerBuilder()
+
+    builder.settingsBlock()
+
+    return builder.build()
+}
+
+//infix fun Int.withStep(step: Int): PropertyHolder {
+//    return DivPropertyHolder(this, step)
+//}
+//
+//operator fun Int.minus(including: Int): PropertyHolder {
+//    return RangePropertyHolder(this, including)
+//}
+
+class SchedulerBuilder(
+    private var seconds: Array<Byte>? = null,
+    private var minutes: Array<Byte>? = null,
+    private var hours: Array<Byte>? = null,
+    private var dayOfMonth: Array<Byte>? = null,
+    private var month: Array<Byte>? = null
+) {
+    private fun <T : TimeBuilder> callAndReturn(
+        initial: Array<Byte>?,
+        builder: T,
+        block: T.() -> Unit
+    ): Array<Byte>? {
+        builder.block()
+
+        val builderValue = builder.build()
+
+        return initial ?.let {
+            builderValue ?.let { _ ->
+                (it + builderValue).distinct().toTypedArray()
+            } ?: builderValue
+        } ?: builderValue
+    }
+
+    fun seconds(block: SecondsBuilder.() -> Unit) {
+        seconds = callAndReturn(
+            seconds,
+            SecondsBuilder(),
+            block
+        )
+    }
+
+    fun minutes(block: MinutesBuilder.() -> Unit) {
+        minutes = callAndReturn(
+            minutes,
+            MinutesBuilder(),
+            block
+        )
+    }
+
+    fun hours(block: HoursBuilder.() -> Unit) {
+        hours = callAndReturn(
+            hours,
+            HoursBuilder(),
+            block
+        )
+    }
+
+    fun dayOfMonth(block: DaysOfMonthBuilder.() -> Unit) {
+        dayOfMonth = callAndReturn(
+            dayOfMonth,
+            DaysOfMonthBuilder(),
+            block
+        )
+    }
+
+    fun months(block: MonthsBuilder.() -> Unit) {
+        month = callAndReturn(
+            month,
+            MonthsBuilder(),
+            block
+        )
+    }
+
+    fun build(): CronDateTimeScheduler {
+        val resultCronDateTimes = mutableListOf(CronDateTime())
+
+        seconds ?.fillWith(resultCronDateTimes) { previousCronDateTime: CronDateTime, currentTime: Byte ->
+            previousCronDateTime.copy(seconds = currentTime)
+        }
+
+        minutes ?.fillWith(resultCronDateTimes) { previousCronDateTime: CronDateTime, currentTime: Byte ->
+            previousCronDateTime.copy(minutes = currentTime)
+        }
+
+        hours ?.fillWith(resultCronDateTimes) { previousCronDateTime: CronDateTime, currentTime: Byte ->
+            previousCronDateTime.copy(hours = currentTime)
+        }
+
+        dayOfMonth ?.fillWith(resultCronDateTimes) { previousCronDateTime: CronDateTime, currentTime: Byte ->
+            previousCronDateTime.copy(dayOfMonth = currentTime)
+        }
+
+        month ?.fillWith(resultCronDateTimes) { previousCronDateTime: CronDateTime, currentTime: Byte ->
+            previousCronDateTime.copy(month = currentTime)
+        }
+
+        return CronDateTimeScheduler(resultCronDateTimes.toList())
+    }
+}

src/commonMain/kotlin/com/github/insanusmokrassar/krontab/builder/TimeBuilder.kt

@@ -0,0 +1,54 @@
+package com.github.insanusmokrassar.krontab.builder
+
+import com.github.insanusmokrassar.krontab.*
+import com.github.insanusmokrassar.krontab.minutesRange
+import com.github.insanusmokrassar.krontab.monthRange
+import com.github.insanusmokrassar.krontab.secondsRange
+import com.github.insanusmokrassar.krontab.utils.clamp
+
+sealed class TimeBuilder (
+    private val restrictionsRange: IntRange
+) {
+    private var result: Set<Int>? = null
+
+    fun allowAll() {
+        result = null
+    }
+
+    infix fun include(array: Array<Int>) {
+        val clamped = array.map { it.clamp(restrictionsRange) } + (result ?: emptySet())
+        result = clamped.toSet()
+    }
+
+    infix fun at(value: Int) {
+        result = (result ?: emptySet()) + value.clamp(restrictionsRange)
+    }
+
+    inline infix fun from(value: Int) = value
+
+    infix fun Int.every(delay: Int): Array<Int> {
+        val progression = clamp(restrictionsRange) .. restrictionsRange.last step delay
+        val result = progression.toSet().toTypedArray()
+
+        this@TimeBuilder include result
+
+        return result
+    }
+
+    infix fun Int.upTo(endIncluding: Int): Array<Int> {
+        val progression = clamp(restrictionsRange) .. endIncluding.clamp(restrictionsRange)
+        val result = progression.toSet().toTypedArray()
+
+        this@TimeBuilder include result
+
+        return result
+    }
+
+    internal fun build() = result ?.map { it.toByte() } ?.toTypedArray()
+}
+
+class SecondsBuilder : TimeBuilder(secondsRange)
+class MinutesBuilder : TimeBuilder(minutesRange)
+class HoursBuilder : TimeBuilder(hoursRange)
+class DaysOfMonthBuilder : TimeBuilder(dayOfMonthRange)
+class MonthsBuilder : TimeBuilder(monthRange)