feat(core): add requirements provider

GH-3

src/main/kotlin/com/goulash/core/ActivityManager.kt

@@ -2,7 +2,9 @@ package com.goulash.core
 
 import com.goulash.core.activity.Activity
 import com.goulash.core.domain.Actor
+import org.springframework.stereotype.Service
 
+@Service
 class ActivityManager {
     private val actorActivities: MutableMap<Actor, Activity> = mutableMapOf()
     private val activityDurations: MutableMap<Actor, Double> = mutableMapOf()

src/main/kotlin/com/goulash/core/RequirementsProvider.kt

@@ -0,0 +1,37 @@
+package com.goulash.core
+
+import com.goulash.core.domain.Actor
+
+/**
+ * Stores provided requirements to be accessed by individual [Actor]s
+ * to satisfy their activity requirements.
+ */
+object RequirementsProvider {
+    private val providedRequirements: MutableMap<Actor, MutableList<String>> = mutableMapOf()
+
+    fun satisfy(actor: Actor, requirement: String) {
+        val provided = providedRequirements.getOrDefault(actor, null)
+        if (provided == null) {
+            providedRequirements[actor] = mutableListOf(requirement)
+        } else {
+            provided.add(requirement)
+        }
+    }
+
+    fun providesAll(actor: Actor): List<String> {
+        return providedRequirements.getOrElse(actor) { listOf() }
+    }
+
+    fun isProvided(actor: Actor, requirement: String): Boolean {
+        val provided = providedRequirements.getOrElse(actor) { mutableListOf() }
+        if (provided.isEmpty()) return false
+        return provided.contains(requirement)
+    }
+
+    fun consume(actor: Actor, requirement: String): Boolean {
+        val provided = providedRequirements.getOrElse(actor) { mutableListOf() }
+        if (provided.isEmpty()) return false
+        return provided.remove(requirement)
+    }
+
+}

src/test/kotlin/com/goulash/core/RequirementsProviderTest.kt

@@ -0,0 +1,68 @@
+package com.goulash.core
+
+import assertk.assertThat
+import assertk.assertions.contains
+import assertk.assertions.containsAll
+import assertk.assertions.hasSize
+import assertk.assertions.isEmpty
+import assertk.assertions.isFalse
+import assertk.assertions.isTrue
+import com.goulash.core.domain.Actor
+import io.mockk.mockk
+import org.junit.jupiter.api.Assertions.*
+import org.junit.jupiter.api.Test
+
+internal class RequirementsProviderTest {
+    @Test
+    fun `should add multiple requirements`() {
+        val actor: Actor = mockk()
+        RequirementsProvider.satisfy(actor, "food")
+        RequirementsProvider.satisfy(actor, "food")
+
+        assertThat(RequirementsProvider.providesAll(actor)).hasSize(2)
+        assertThat(RequirementsProvider.providesAll(actor)).containsAll("food", "food")
+    }
+
+    @Test
+    fun `should consume multiple requirements`() {
+        val actor: Actor = mockk()
+        RequirementsProvider.satisfy(actor, "food")
+        RequirementsProvider.satisfy(actor, "food")
+
+        assertThat(RequirementsProvider.consume(actor, "food")).isTrue()
+        assertThat(RequirementsProvider.isProvided(actor, "food")).isTrue()
+        assertThat(RequirementsProvider.consume(actor, "food")).isTrue()
+        assertThat(RequirementsProvider.isProvided(actor, "food")).isFalse()
+    }
+
+    @Test
+    fun `should consume requirement`() {
+        val actor: Actor = mockk()
+        RequirementsProvider.satisfy(actor, "food")
+
+        assertThat(RequirementsProvider.consume(actor, "food")).isTrue()
+        assertThat(RequirementsProvider.isProvided(actor, "food")).isFalse()
+    }
+
+    @Test
+    fun `should check if requirement is provided`() {
+        val actor: Actor = mockk()
+        RequirementsProvider.satisfy(actor, "food")
+
+        assertThat(RequirementsProvider.isProvided(actor, "food")).isTrue()
+    }
+
+    @Test
+    fun `should return empty list`() {
+        assertThat(RequirementsProvider.providesAll(mockk())).isEmpty()
+    }
+
+    @Test
+    fun `should add requirement to the provided map`() {
+        val actor: Actor = mockk()
+        RequirementsProvider.satisfy(actor, "food")
+        assertThat(RequirementsProvider.providesAll(actor)).contains("food")
+    }
+
+}
+

src/test/kotlin/com/goulash/simulation/SimpleSimulationTest.kt

@@ -3,12 +3,15 @@ package com.goulash.simulation
 import assertk.assertThat
 import assertk.assertions.isEqualTo
 import assertk.assertions.isNull
+import com.goulash.core.ActivityManager
 import com.goulash.core.domain.Container
 import com.goulash.factory.BaseActorFactory
 import com.goulash.script.loader.ScriptLoader
 import org.junit.jupiter.api.BeforeAll
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.io.TempDir
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.boot.test.context.SpringBootTest
 import java.io.File
 
 class SimpleSimulationTest {
@@ -21,6 +24,8 @@ class SimpleSimulationTest {
 
         repeat(5) { manualSimulationRunner.tick() }
         assertThat(person.urges.getUrgeOrNull("hunger")).isEqualTo(5.0)
+        repeat(5) { manualSimulationRunner.tick() }
+        assertThat(person.urges.getUrgeOrNull("hunger")).isNull()
     }
 
     @Test