test(unit): compression service test

src/main/java/com/ddf/vodsystem/services/media/CompressionService.java

@@ -106,7 +106,7 @@ public class CompressionService {
         return command;
     }
 
-    private List<String> buildCommand(Path inputFile, Path outputFile, ClipOptions clipOptions) {
+    protected List<String> buildCommand(Path inputFile, Path outputFile, ClipOptions clipOptions) {
         List<String> command = new ArrayList<>();
         command.add("ffmpeg");
         command.add("-progress");

src/test/java/com/ddf/vodsystem/services/media/CompressionServiceTest.java

@@ -0,0 +1,159 @@
+package com.ddf.vodsystem.services.media;
+
+import com.ddf.vodsystem.dto.ClipOptions;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.mockito.Mock;
+
+import java.nio.file.Path;
+import java.util.List;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+class CompressionServiceTest {
+    @Mock
+    private CommandRunner commandRunner;
+
+    private CompressionService compressionService;
+
+    @BeforeEach
+    void setUp() {
+        compressionService = new CompressionService(commandRunner);
+    }
+
+    @Test
+    void buildCommand_minimalClipOptions_smallCommand() {
+        Path input = Path.of("/tmp/input.mp4");
+        Path output = Path.of("/tmp/output.mp4");
+        ClipOptions options = new ClipOptions();
+        options.setTitle("hello");
+        options.setStartPoint(10.0f);
+        options.setDuration(30.0f);
+
+        List<String> command = compressionService.buildCommand(input, output, options);
+
+        assertThat(command).containsSubsequence("-ss", "10.0");
+        assertThat(command).containsSubsequence("-t", "30.0");
+        assertThat(command).containsSubsequence("-i", input.toAbsolutePath().toString());
+
+        assertThat(command).doesNotContain("-vf");
+        assertThat(command).doesNotContain("-b:v");
+
+        assertThat(command).endsWith(output.toAbsolutePath().toString());
+    }
+
+    @Test
+    void buildCommand_hasFileSize_hasBitrateOptions() {
+        Path input = Path.of("/tmp/input.mp4");
+        Path output = Path.of("/tmp/output.mp4");
+        ClipOptions options = new ClipOptions();
+
+        options.setTitle("hello");
+        options.setStartPoint(10.0f);
+        options.setDuration(30.0f);
+        options.setFileSize(10.0f);
+
+        List<String> command = compressionService.buildCommand(input, output, options);
+
+        assertThat(command).contains("-b:v", "-b:a");
+        int bvIndex = command.indexOf("-b:v");
+        int baIndex = command.indexOf("-b:a");
+
+        assertThat(command.get(bvIndex + 1)).isNotBlank().endsWith("k");
+        assertThat(command.get(baIndex + 1)).isNotBlank().endsWith("k");
+    }
+
+    @Test
+    void buildCommand_hasWidthHeight_hasVideoFilters() {
+        Path input = Path.of("/tmp/input.mp4");
+        Path output = Path.of("/tmp/output.mp4");
+        ClipOptions options = new ClipOptions();
+
+        options.setTitle("hello");
+        options.setStartPoint(10.0f);
+        options.setDuration(30.0f);
+        options.setWidth(1920);
+        options.setHeight(1080);
+
+        List<String> command = compressionService.buildCommand(input, output, options);
+
+        assertThat(command).containsSequence("-vf", "scale=1920:1080");
+    }
+
+    @Test
+    void buildCommand_onlyWidth_aspectRatioKept() {
+        Path input = Path.of("/tmp/input.mp4");
+        Path output = Path.of("/tmp/output.mp4");
+        ClipOptions options = new ClipOptions();
+
+        options.setTitle("hello");
+        options.setStartPoint(10.0f);
+        options.setDuration(30.0f);
+        options.setWidth(1920);
+
+        List<String> command = compressionService.buildCommand(input, output, options);
+
+        assertThat(command).containsSequence("-vf", "scale=1920:-1");
+    }
+
+    @Test
+    void buildCommand_onlyHeight_aspectRatioKept() {
+        Path input = Path.of("/tmp/input.mp4");
+        Path output = Path.of("/tmp/output.mp4");
+        ClipOptions options = new ClipOptions();
+
+        options.setTitle("hello");
+        options.setStartPoint(10.0f);
+        options.setDuration(30.0f);
+        options.setHeight(1080);
+
+        List<String> command = compressionService.buildCommand(input, output, options);
+
+        assertThat(command).containsSequence("-vf", "scale=-1:1080");
+    }
+
+    @Test
+    void buildCommand_onlyHasFps_hasNoScaleFilter() {
+        Path input = Path.of("/tmp/input.mp4");
+        Path output = Path.of("/tmp/output.mp4");
+        ClipOptions options = new ClipOptions();
+
+        options.setTitle("hello");
+        options.setStartPoint(10.0f);
+        options.setDuration(30.0f);
+        options.setFps(60f);
+
+        List<String> command = compressionService.buildCommand(input, output, options);
+
+        assertThat(command).containsSequence("-vf", "fps=60.0");
+    }
+
+    @Test
+    void buildCommand_noInputFile_throwsNullPointer() {
+        Path output = Path.of("/tmp/output.mp4");
+        ClipOptions options = new ClipOptions();
+
+        options.setTitle("hello");
+        options.setStartPoint(10.0f);
+        options.setDuration(30.0f);
+
+        assertThrows(NullPointerException.class, () ->
+                compressionService.buildCommand(null, output, options)
+        );
+    }
+
+    @Test
+    void buildCommand_noOutputFile_throwsNullPointer() {
+        Path input = Path.of("/tmp/output.mp4");
+        ClipOptions options = new ClipOptions();
+
+        options.setTitle("hello");
+        options.setStartPoint(10.0f);
+        options.setDuration(30.0f);
+
+        assertThrows(NullPointerException.class, () ->
+                compressionService.buildCommand(input, null, options)
+        );
+    }
+}