Add new limit options

app/src/main/java/io/timelimit/android/logic/RemainingSessionDuration.kt

@@ -0,0 +1,62 @@
+/*
+ * TimeLimit Copyright <C> 2019- 2020 Jonas Lochmann
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation version 3 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+package io.timelimit.android.logic
+
+import io.timelimit.android.data.model.SessionDuration
+import io.timelimit.android.data.model.TimeLimitRule
+
+object RemainingSessionDuration {
+    fun min(a: Long?, b: Long?): Long? {
+        if (a == null && b == null) {
+            return null
+        } else if (a == null) {
+            return b
+        } else if (b == null) {
+            return a
+        } else {
+            return a.coerceAtMost(b)
+        }
+    }
+
+    fun getRemainingSessionDuration(
+            rules: List<TimeLimitRule>, durationsOfCategory: List<SessionDuration>,
+            dayOfWeek: Int, minuteOfDay: Int, timestamp: Long
+    ): Long? {
+        var result: Long? = null
+
+        rules.forEach { rule ->
+            if (
+                    rule.sessionDurationLimitEnabled &&
+                            rule.dayMask.toInt() and (1 shl dayOfWeek) != 0 &&
+                            rule.startMinuteOfDay <= minuteOfDay && rule.endMinuteOfDay >= minuteOfDay
+            ) {
+                val remaining = durationsOfCategory.find {
+                    it.startMinuteOfDay == rule.startMinuteOfDay &&
+                            it.endMinuteOfDay == rule.endMinuteOfDay &&
+                            it.maxSessionDuration == rule.sessionDurationMilliseconds &&
+                            it.sessionPauseDuration == rule.sessionPauseMilliseconds &&
+                            it.lastUsage + it.sessionPauseDuration > timestamp
+                }?.let { durationItem ->
+                    (durationItem.maxSessionDuration - durationItem.lastSessionDuration).coerceAtLeast(0)
+                } ?: rule.sessionDurationMilliseconds.toLong()
+
+                result = min(result, remaining)
+            }
+        }
+
+        return result
+    }
+}