feat: add GribFileManager interface and InMemoryGribFileManager

3 files changed, 184 insertions, 0 deletions

diff --git a/android-app/app/src/main/kotlin/org/terst/nav/data/storage/GribFileManager.kt b/android-app/app/src/main/kotlin/org/terst/nav/data/storage/GribFileManager.kt
new file mode 100644
index 0000000..e17e5ca
--- /dev/null
+++ b/android-app/app/src/main/kotlin/org/terst/nav/data/storage/GribFileManager.kt
@@ -0,0 +1,42 @@
+package org.terst.nav.data.storage
+
+import org.terst.nav.data.model.GribFile
+import org.terst.nav.data.model.GribRegion
+import java.time.Instant
+
+interface GribFileManager {
+    /** Save metadata for a newly-downloaded GRIB file. */
+    fun saveMetadata(file: GribFile)
+    /** Return all stored GRIB files for [region], newest first. */
+    fun listFiles(region: GribRegion): List<GribFile>
+    /** Return the most-recently-downloaded GRIB file for [region], or null if none. */
+    fun latestFile(region: GribRegion): GribFile?
+    /** Delete a specific GRIB file's metadata and from disk. Returns true if deleted. */
+    fun delete(file: GribFile): Boolean
+    /** Delete all GRIB files older than [before]. Returns count of deleted files. */
+    fun purgeOlderThan(before: Instant): Int
+    /** Total size in bytes of all stored GRIB files. */
+    fun totalSizeBytes(): Long
+}
+
+class InMemoryGribFileManager : GribFileManager {
+    private val files = mutableListOf<GribFile>()
+
+    override fun saveMetadata(file: GribFile) { files.add(file) }
+
+    override fun listFiles(region: GribRegion): List<GribFile> =
+        files.filter { it.region.name == region.name }
+             .sortedByDescending { it.downloadedAt }
+
+    override fun latestFile(region: GribRegion): GribFile? = listFiles(region).firstOrNull()
+
+    override fun delete(file: GribFile): Boolean = files.remove(file)
+
+    override fun purgeOlderThan(before: Instant): Int {
+        val toRemove = files.filter { it.downloadedAt.isBefore(before) }
+        files.removeAll(toRemove)
+        return toRemove.size
+    }
+
+    override fun totalSizeBytes(): Long = files.sumOf { it.sizeBytes }
+}
diff --git a/test-runner/src/main/kotlin/org/terst/nav/data/storage/GribFileManager.kt b/test-runner/src/main/kotlin/org/terst/nav/data/storage/GribFileManager.kt
new file mode 100644
index 0000000..e17e5ca
--- /dev/null
+++ b/test-runner/src/main/kotlin/org/terst/nav/data/storage/GribFileManager.kt
@@ -0,0 +1,42 @@
+package org.terst.nav.data.storage
+
+import org.terst.nav.data.model.GribFile
+import org.terst.nav.data.model.GribRegion
+import java.time.Instant
+
+interface GribFileManager {
+    /** Save metadata for a newly-downloaded GRIB file. */
+    fun saveMetadata(file: GribFile)
+    /** Return all stored GRIB files for [region], newest first. */
+    fun listFiles(region: GribRegion): List<GribFile>
+    /** Return the most-recently-downloaded GRIB file for [region], or null if none. */
+    fun latestFile(region: GribRegion): GribFile?
+    /** Delete a specific GRIB file's metadata and from disk. Returns true if deleted. */
+    fun delete(file: GribFile): Boolean
+    /** Delete all GRIB files older than [before]. Returns count of deleted files. */
+    fun purgeOlderThan(before: Instant): Int
+    /** Total size in bytes of all stored GRIB files. */
+    fun totalSizeBytes(): Long
+}
+
+class InMemoryGribFileManager : GribFileManager {
+    private val files = mutableListOf<GribFile>()
+
+    override fun saveMetadata(file: GribFile) { files.add(file) }
+
+    override fun listFiles(region: GribRegion): List<GribFile> =
+        files.filter { it.region.name == region.name }
+             .sortedByDescending { it.downloadedAt }
+
+    override fun latestFile(region: GribRegion): GribFile? = listFiles(region).firstOrNull()
+
+    override fun delete(file: GribFile): Boolean = files.remove(file)
+
+    override fun purgeOlderThan(before: Instant): Int {
+        val toRemove = files.filter { it.downloadedAt.isBefore(before) }
+        files.removeAll(toRemove)
+        return toRemove.size
+    }
+
+    override fun totalSizeBytes(): Long = files.sumOf { it.sizeBytes }
+}
diff --git a/test-runner/src/test/kotlin/org/terst/nav/data/storage/GribFileManagerTest.kt b/test-runner/src/test/kotlin/org/terst/nav/data/storage/GribFileManagerTest.kt
new file mode 100644
index 0000000..95ca546
--- /dev/null
+++ b/test-runner/src/test/kotlin/org/terst/nav/data/storage/GribFileManagerTest.kt
@@ -0,0 +1,100 @@
+package org.terst.nav.data.storage
+
+import org.junit.Assert.*
+import org.junit.Test
+import org.terst.nav.data.model.GribFile
+import org.terst.nav.data.model.GribRegion
+import java.time.Instant
+
+private fun makeGribFile(
+    region: GribRegion,
+    downloadedAt: Instant,
+    sizeBytes: Long = 1024L
+): GribFile = GribFile(
+    region = region,
+    modelRunTime = downloadedAt.minusSeconds(6 * 3600),
+    forecastHours = 48,
+    downloadedAt = downloadedAt,
+    filePath = "/tmp/grib_${region.name}_${downloadedAt.epochSecond}.grb2",
+    sizeBytes = sizeBytes
+)
+
+class GribFileManagerTest {
+    private val manager = InMemoryGribFileManager()
+    private val regionA = GribRegion("Atlantic", 30.0, 60.0, -50.0, 0.0)
+    private val regionB = GribRegion("Pacific", 20.0, 50.0, -160.0, -100.0)
+    private val baseTime = Instant.parse("2026-01-01T12:00:00Z")
+
+    @Test
+    fun saveMetadata_addsFileToList() {
+        val file = makeGribFile(regionA, baseTime)
+        manager.saveMetadata(file)
+        assertEquals(listOf(file), manager.listFiles(regionA))
+    }
+
+    @Test
+    fun listFiles_returnsOnlyFilesForRegion() {
+        val fileA = makeGribFile(regionA, baseTime)
+        val fileB = makeGribFile(regionB, baseTime)
+        manager.saveMetadata(fileA)
+        manager.saveMetadata(fileB)
+        assertEquals(listOf(fileA), manager.listFiles(regionA))
+        assertEquals(listOf(fileB), manager.listFiles(regionB))
+    }
+
+    @Test
+    fun listFiles_returnsNewestFirst() {
+        val older = makeGribFile(regionA, baseTime)
+        val newer = makeGribFile(regionA, baseTime.plusSeconds(3600))
+        manager.saveMetadata(older)
+        manager.saveMetadata(newer)
+        assertEquals(listOf(newer, older), manager.listFiles(regionA))
+    }
+
+    @Test
+    fun latestFile_returnsNull_whenNoFiles() {
+        assertNull(manager.latestFile(regionA))
+    }
+
+    @Test
+    fun latestFile_returnsMostRecent() {
+        val older = makeGribFile(regionA, baseTime)
+        val newer = makeGribFile(regionA, baseTime.plusSeconds(3600))
+        manager.saveMetadata(older)
+        manager.saveMetadata(newer)
+        assertEquals(newer, manager.latestFile(regionA))
+    }
+
+    @Test
+    fun delete_removesFile_returnsTrue() {
+        val file = makeGribFile(regionA, baseTime)
+        manager.saveMetadata(file)
+        assertTrue(manager.delete(file))
+        assertTrue(manager.listFiles(regionA).isEmpty())
+    }
+
+    @Test
+    fun delete_returnsFalse_whenNotPresent() {
+        val file = makeGribFile(regionA, baseTime)
+        assertFalse(manager.delete(file))
+    }
+
+    @Test
+    fun purgeOlderThan_removesOldFiles_returnsCount() {
+        val old = makeGribFile(regionA, baseTime)
+        val recent = makeGribFile(regionA, baseTime.plusSeconds(7200))
+        manager.saveMetadata(old)
+        manager.saveMetadata(recent)
+        val cutoff = baseTime.plusSeconds(3600)
+        val deleted = manager.purgeOlderThan(cutoff)
+        assertEquals(1, deleted)
+        assertEquals(listOf(recent), manager.listFiles(regionA))
+    }
+
+    @Test
+    fun totalSizeBytes_sumsAllFiles() {
+        manager.saveMetadata(makeGribFile(regionA, baseTime, sizeBytes = 1000L))
+        manager.saveMetadata(makeGribFile(regionB, baseTime, sizeBytes = 2000L))
+        assertEquals(3000L, manager.totalSizeBytes())
+    }
+}