Streamline text & sentiment analysis architecture

Includes the following:
- Created Service Layer Separation to eliminate fat services and improve maintainability
- Added Engines for core logic
- Added Classifiers/Calculators as small, focused components
- Implemented Managers for IO/caching
- Externalized configuration using @ConfigurationProperties to remove hardcoded values
- Introduced classpath-based word list resources and added loader support for classpath
- Removed explicit H2 dialect (auto-detected by Spring Boot)
- Centralized constants used throughout the application

Author: kappil-garg

src/main/java/com/kapil/verbametrics/config/ReadabilityAnalysisProperties.java

@@ -0,0 +1,68 @@
+package com.kapil.verbametrics.config;
+
+import lombok.Data;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.context.annotation.Configuration;
+
+/**
+ * Configuration properties for readability analysis.
+ * Contains coefficients for Flesch-Kincaid and Flesch Reading Ease for reading and complexity levels.
+ *
+ * @author Kapil Garg
+ */
+@Data
+@Configuration
+@ConfigurationProperties(prefix = "readability.analysis")
+public class ReadabilityAnalysisProperties {
+
+    /**
+     * Reading level thresholds
+     */
+    private ReadingLevels readingLevels = new ReadingLevels();
+
+    /**
+     * Flesch-Kincaid formula coefficients
+     */
+    private FleschKincaid fleschKincaid = new FleschKincaid();
+
+    /**
+     * Complexity level thresholds
+     */
+    private ComplexityLevels complexityLevels = new ComplexityLevels();
+
+    /**
+     * Flesch Reading Ease formula coefficients
+     */
+    private FleschReadingEase fleschReadingEase = new FleschReadingEase();
+
+    @Data
+    public static class ReadingLevels {
+        private double elementary = 6.0;
+        private double middleSchool = 9.0;
+        private double highSchool = 12.0;
+        private double college = 16.0;
+    }
+
+    @Data
+    public static class FleschKincaid {
+        private double sentenceLengthMultiplier = 0.39;
+        private double syllablesPerWordMultiplier = 11.8;
+        private double constant = -15.59;
+    }
+
+    @Data
+    public static class ComplexityLevels {
+        private double veryEasy = 80.0;
+        private double easy = 60.0;
+        private double moderate = 40.0;
+        private double difficult = 20.0;
+    }
+
+    @Data
+    public static class FleschReadingEase {
+        private double constant = 206.835;
+        private double sentenceLengthMultiplier = 1.015;
+        private double syllablesPerWordMultiplier = 84.6;
+    }
+
+}

src/main/java/com/kapil/verbametrics/config/SentimentAnalysisProperties.java

@@ -0,0 +1,67 @@
+package com.kapil.verbametrics.config;
+
+import lombok.Data;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.context.annotation.Configuration;
+
+import java.util.List;
+
+/**
+ * Configuration properties for sentiment analysis.
+ * Contains thresholds for sentiment classification, confidence levels, text processing options, and word lists.
+ *
+ * @author Kapil Garg
+ */
+@Data
+@Configuration
+@ConfigurationProperties(prefix = "sentiment.analysis")
+public class SentimentAnalysisProperties {
+
+    /**
+     * Word list configuration
+     */
+    private WordLists wordLists = new WordLists();
+
+    /**
+     * Sentiment thresholds for classification
+     */
+    private Thresholds thresholds = new Thresholds();
+
+    /**
+     * Text processing configuration
+     */
+    private TextProcessing textProcessing = new TextProcessing();
+
+    /**
+     * Confidence level thresholds
+     */
+    private ConfidenceLevels confidenceLevels = new ConfidenceLevels();
+
+    @Data
+    public static class WordLists {
+        private String positiveWordsPath;
+        private String negativeWordsPath;
+        private List<String> positiveWords = List.of();
+        private List<String> negativeWords = List.of();
+    }
+
+    @Data
+    public static class Thresholds {
+        private double positive = 0.1;
+        private double negative = -0.1;
+    }
+
+    @Data
+    public static class TextProcessing {
+        private String wordSeparator = "\\W+";
+        private boolean caseSensitive = false;
+        private boolean removePunctuation = true;
+    }
+
+    @Data
+    public static class ConfidenceLevels {
+        private double high = 0.8;
+        private double medium = 0.6;
+    }
+
+}

src/main/java/com/kapil/verbametrics/config/SentimentWordProperties.java

@@ -29,14 +29,24 @@ public record BasicTextStatistics(
      */
     private static void validateInputs(int wordCount, int sentenceCount, int characterCount,
                                        int characterCountNoSpaces, int paragraphCount) {
-        if (wordCount < 0) throw new IllegalArgumentException("Word count cannot be negative");
-        if (sentenceCount < 0) throw new IllegalArgumentException("Sentence count cannot be negative");
-        if (characterCount < 0) throw new IllegalArgumentException("Character count cannot be negative");
-        if (characterCountNoSpaces < 0)
+        if (wordCount < 0) {
+            throw new IllegalArgumentException("Word count cannot be negative");
+        }
+        if (sentenceCount < 0) {
+            throw new IllegalArgumentException("Sentence count cannot be negative");
+        }
+        if (characterCount < 0) {
+            throw new IllegalArgumentException("Character count cannot be negative");
+        }
+        if (characterCountNoSpaces < 0) {
             throw new IllegalArgumentException("Character count without spaces cannot be negative");
-        if (paragraphCount < 0) throw new IllegalArgumentException("Paragraph count cannot be negative");
-        if (characterCountNoSpaces > characterCount)
+        }
+        if (paragraphCount < 0) {
+            throw new IllegalArgumentException("Paragraph count cannot be negative");
+        }
+        if (characterCountNoSpaces > characterCount) {
             throw new IllegalArgumentException("Character count without spaces cannot exceed total character count");
+        }
     }
 
     @Override

src/main/java/com/kapil/verbametrics/constants/SentimentConstants.java

@@ -43,62 +43,6 @@ private static void validateInputs(double fleschKincaidScore, double fleschReadi
         }
     }
 
-    /**
-     * Determines the reading level description based on Flesch-Kincaid score.
-     *
-     * @return the reading level description
-     */
-    public String getReadingLevelDescription() {
-        if (fleschKincaidScore <= 6) {
-            return "Elementary";
-        } else if (fleschKincaidScore <= 9) {
-            return "Middle School";
-        } else if (fleschKincaidScore <= 12) {
-            return "High School";
-        } else if (fleschKincaidScore <= 16) {
-            return "College";
-        } else {
-            return "Graduate";
-        }
-    }
-
-    /**
-     * Determines the complexity level based on Flesch Reading Ease score.
-     *
-     * @return the complexity level
-     */
-    public String getComplexityLevel() {
-        if (fleschReadingEase >= 80) {
-            return "Very Easy";
-        } else if (fleschReadingEase >= 60) {
-            return "Easy";
-        } else if (fleschReadingEase >= 40) {
-            return "Moderate";
-        } else if (fleschReadingEase >= 20) {
-            return "Difficult";
-        } else {
-            return "Very Difficult";
-        }
-    }
-
-    /**
-     * Checks if the text is easy to read.
-     *
-     * @return true if the text is easy to read
-     */
-    public boolean isEasyToRead() {
-        return fleschReadingEase >= 60;
-    }
-
-    /**
-     * Checks if the text is difficult to read.
-     *
-     * @return true if the text is difficult to read
-     */
-    public boolean isDifficultToRead() {
-        return fleschReadingEase < 40;
-    }
-
     @Override
     public String toString() {
         return """

src/main/java/com/kapil/verbametrics/constants/TextAnalysisConstants.java

@@ -1,6 +1,6 @@
 package com.kapil.verbametrics.domain;
 
-import com.kapil.verbametrics.constants.SentimentConstants;
+import com.kapil.verbametrics.util.VerbaMetricsConstants;
 
 /**
  * Domain record representing sentiment analysis results.
@@ -12,11 +12,11 @@ public record SentimentScore(
         double confidence,
         double score
 ) {
-    
+
     public SentimentScore {
         validateInputs(label, confidence, score);
     }
-    
+
     /**
      * Validates the input parameters to ensure they are valid.
      *
@@ -36,49 +36,40 @@ private static void validateInputs(String label, double confidence, double score
             throw new IllegalArgumentException("Score must be between -1.0 and 1.0");
         }
     }
-    
+
     /**
      * Determines the confidence level based on the confidence value.
      *
      * @return the confidence level as a string
      */
     public String getConfidenceLevel() {
-        if (confidence >= SentimentConstants.HIGH_CONFIDENCE) {
-            return "HIGH";
-        } else if (confidence >= SentimentConstants.MEDIUM_CONFIDENCE) {
-            return "MEDIUM";
+        if (confidence >= VerbaMetricsConstants.HIGH_CONFIDENCE) {
+            return VerbaMetricsConstants.K_HIGH;
+        } else if (confidence >= VerbaMetricsConstants.MEDIUM_CONFIDENCE) {
+            return VerbaMetricsConstants.K_MEDIUM;
         } else {
-            return "LOW";
+            return VerbaMetricsConstants.K_LOW;
         }
     }
-    
+
     /**
      * Checks if the sentiment is positive.
      *
      * @return true if the sentiment is positive
      */
     public boolean isPositive() {
-        return SentimentConstants.POSITIVE.equals(label);
+        return VerbaMetricsConstants.POSITIVE.equals(label);
     }
-    
+
     /**
      * Checks if the sentiment is negative.
      *
      * @return true if the sentiment is negative
      */
     public boolean isNegative() {
-        return SentimentConstants.NEGATIVE.equals(label);
+        return VerbaMetricsConstants.NEGATIVE.equals(label);
     }
-    
-    /**
-     * Checks if the sentiment is neutral.
-     *
-     * @return true if the sentiment is neutral
-     */
-    public boolean isNeutral() {
-        return SentimentConstants.NEUTRAL.equals(label);
-    }
-    
+
     @Override
     public String toString() {
         return """
@@ -89,5 +80,5 @@ public String toString() {
                 label, confidence, score, getConfidenceLevel()
         );
     }
-    
+
 }