Added comments to explain stuff.

gymboard-api/.gitignore

@@ -32,3 +32,4 @@ build/
 .vscode/
 
 .sample_data
+exercise_submission_temp_files/

gymboard-api/src/main/java/nl/andrewlalis/gymboard_api/model/exercise/ExerciseSubmission.java

@@ -10,11 +10,22 @@ import java.time.LocalDateTime;
 @Entity
 @Table(name = "exercise_submission")
 public class ExerciseSubmission {
+	/**
+	 * The status of a submission.
+	 * <ul>
+	 *     <li>Each submission starts as WAITING.</li>
+	 *     <li>The status changes to PROCESSING once it's picked up for processing.</li>
+	 *     <li>If processing fails, the status changes to FAILED.</li>
+	 *     <li>If processing is successful, the status changes to COMPLETED.</li>
+	 *     <li>Once a completed submission is verified either automatically or manually, it's set to VERIFIED.</li>
+	 * </ul>
+	 */
 	public enum Status {
 		WAITING,
 		PROCESSING,
 		FAILED,
-		COMPLETED
+		COMPLETED,
+		VERIFIED
 	}
 
 	@Id

gymboard-api/src/main/java/nl/andrewlalis/gymboard_api/service/ExerciseSubmissionService.java

@@ -211,6 +211,17 @@ public class ExerciseSubmissionService {
 		log.info("Processing of submission {} complete.", submission.getId());
 	}
 
+	/**
+	 * Uses the `ffmpeg` system command to process a raw input video and produce
+	 * a compressed, reduced-size output video that's ready for usage in the
+	 * application.
+	 * @param dir The working directory.
+	 * @param inFile The input file to read from.
+	 * @param outFile The output file to write to. MUST have a ".mp4" extension.
+	 * @throws IOException If a filesystem error occurs.
+	 * @throws CommandFailedException If the ffmpeg command fails.
+	 * @throws InterruptedException If the ffmpeg command is interrupted.
+	 */
 	private void processVideo(Path dir, Path inFile, Path outFile) throws IOException, InterruptedException {
 		Path tmpStdout = Files.createTempFile(dir, "stdout-", ".log");
 		Path tmpStderr = Files.createTempFile(dir, "stderr-", ".log");
@@ -240,6 +251,7 @@ public class ExerciseSubmissionService {
 		String reductionFactorStr = String.format("%.3f%%", reductionFactor * 100);
 		log.info("Processed video from {} bytes to {} bytes in {} seconds, {} reduction.", startSize, endSize, dur.getSeconds(), reductionFactorStr);
 
+		// Delete the logs if everything was successful.
 		Files.deleteIfExists(tmpStdout);
 		Files.deleteIfExists(tmpStderr);
 	}