feat: implement SqlQueryFilterService for dynamic SQL query filtering

Author: mjabascal10

backend/src/main/java/com/park/utmstack/service/elasticsearch/sql/SqlQueryFilterService.java

@@ -0,0 +1,377 @@
+package com.park.utmstack.service.elasticsearch.sql;
+
+import com.park.utmstack.domain.chart_builder.types.query.FilterType;
+import com.park.utmstack.domain.chart_builder.types.query.OperatorType;
+import org.springframework.stereotype.Service;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Collectors;
+
+@Service
+public class SqlQueryFilterService {
+
+    /**
+     * Applies the given filters to the base SQL query by generating a dynamic WHERE clause.
+     * - Handles all FilterType operators.
+     * - Treats @timestamp specially (relative and absolute ranges).
+     * - Merges the generated WHERE with an existing WHERE if present.
+     */
+    public String applyFilters(String baseSql, List<FilterType> filters) {
+        if (filters == null || filters.isEmpty()) {
+            return baseSql;
+        }
+
+        List<String> andConditions = new ArrayList<>();
+        List<String> orConditions = new ArrayList<>();
+
+        for (FilterType filter : filters) {
+
+            // Special handling for @timestamp: relative/absolute time logic
+            if ("@timestamp".equals(filter.getField())) {
+                andConditions.add(buildTimestampCondition(filter));
+                continue;
+            }
+
+            String sqlCondition = toSqlCondition(filter);
+
+            // IS_ONE_OF_TERMS_OR is explicitly an OR-group operator
+            if (filter.getOperator() == OperatorType.IS_ONE_OF_TERMS_OR) {
+                orConditions.add(sqlCondition);
+            } else {
+                andConditions.add(sqlCondition);
+            }
+        }
+
+        String whereClause = combineConditions(andConditions, orConditions);
+        return mergeSql(baseSql, whereClause);
+    }
+
+    // -------------------------------------------------------------------------
+    //  TIMESTAMP HANDLING
+    // -------------------------------------------------------------------------
+
+    /**
+     * Builds the SQL condition for @timestamp.
+     * The value may be:
+     * - A List<?> of two elements (for IS_BETWEEN)
+     * - A single String (for > or <=)
+     */
+    private String buildTimestampCondition(FilterType f) {
+
+        Object rawValue = f.getValue();
+
+        switch (f.getOperator()) {
+
+            case IS_BETWEEN:
+                if (!(rawValue instanceof List<?> list) || list.size() != 2) {
+                    throw new IllegalArgumentException("@timestamp IS_BETWEEN requires a list of two values");
+                }
+
+                String from = String.valueOf(list.get(0));
+                String to   = String.valueOf(list.get(1));
+
+                return "@timestamp BETWEEN " + toSqlTime(from) + " AND " + toSqlTime(to);
+
+            case IS_GREATER_THAN:
+                if (!(rawValue instanceof String singleGt)) {
+                    throw new IllegalArgumentException("@timestamp IS_GREATER_THAN requires a single value");
+                }
+
+                return "@timestamp > " + toSqlTime(singleGt);
+
+            case IS_LESS_THAN_OR_EQUALS:
+                if (!(rawValue instanceof String singleLe)) {
+                    throw new IllegalArgumentException("@timestamp IS_LESS_THAN_OR_EQUALS requires a single value");
+                }
+
+                return "@timestamp <= " + toSqlTime(singleLe);
+
+
+            default:
+                throw new IllegalArgumentException("Unsupported timestamp operator: " + f.getOperator());
+        }
+    }
+
+
+    /**
+     * Converts a logical time value into a SQL expression:
+     * - "now"      -> NOW()
+     * - "now-24h"  -> DATE_SUB(NOW(), INTERVAL 24 HOUR)
+     * - "now-15m"  -> DATE_SUB(NOW(), INTERVAL 15 MINUTE)
+     * - "now-7d"   -> DATE_SUB(NOW(), INTERVAL 7 DAY)
+     * - any other  -> quoted literal (absolute timestamp)
+     */
+    private String toSqlTime(String value) {
+        if ("now".equals(value)) {
+            return "NOW()";
+        }
+
+        if (value.startsWith("now-")) {
+            // Example: now-24h, now-15m, now-7d
+            String number = value.substring(4, value.length() - 1);
+            char unit = value.toLowerCase().charAt(value.length() - 1);
+
+            String sqlUnit = switch (unit) {
+                case 'm' -> "MINUTE";
+                case 'h' -> "HOUR";
+                case 'd' -> "DAY";
+                default -> throw new IllegalArgumentException("Invalid time unit in value: " + value);
+            };
+
+            return "DATE_SUB(NOW(), INTERVAL " + number + " " + sqlUnit + ")";
+        }
+
+        // Absolute timestamp value
+        return "'" + value + "'";
+    }
+
+    // -------------------------------------------------------------------------
+    //  GENERAL OPERATORS
+    // -------------------------------------------------------------------------
+
+    /**
+     * Maps a FilterType to a SQL condition string.
+     * All non-@timestamp operators are handled here.
+     */
+    private String toSqlCondition(FilterType f) {
+
+        String field = f.getField();
+        Object rawValue = f.getValue();
+        List<String> list = asList(rawValue); // safe conversion
+
+        return switch (f.getOperator()) {
+
+            // ---------------------------------------------------------------------
+            // Equality
+            // ---------------------------------------------------------------------
+            case IS -> field + " = '" + list.get(0) + "'";
+
+            case IS_NOT -> field + " <> '" + list.get(0) + "'";
+
+            // ---------------------------------------------------------------------
+            // Text contains
+            // ---------------------------------------------------------------------
+            case CONTAIN -> field + " LIKE '%" + list.get(0) + "%'";
+
+            case DOES_NOT_CONTAIN -> field + " NOT LIKE '%" + list.get(0) + "%'";
+
+            case CONTAIN_ONE_OF ->
+                    "(" + list.stream()
+                            .map(v -> field + " LIKE '%" + v + "%'")
+                            .collect(Collectors.joining(" OR ")) + ")";
+
+            case DOES_NOT_CONTAIN_ONE_OF ->
+                    "(" + list.stream()
+                            .map(v -> field + " NOT LIKE '%" + v + "%'")
+                            .collect(Collectors.joining(" AND ")) + ")";
+
+            // ---------------------------------------------------------------------
+            // List membership
+            // ---------------------------------------------------------------------
+            case IS_ONE_OF ->
+                    field + " IN (" + joinQuoted(list) + ")";
+
+            case IS_NOT_ONE_OF ->
+                    field + " NOT IN (" + joinQuoted(list) + ")";
+
+            case IS_ONE_OF_TERMS ->
+                    field + " IN (" + joinQuoted(list) + ")";
+
+            case IS_ONE_OF_TERMS_OR ->
+                    "(" + list.stream()
+                            .map(v -> field + " = '" + v + "'")
+                            .collect(Collectors.joining(" OR ")) + ")";
+
+            // ---------------------------------------------------------------------
+            // Existence
+            // ---------------------------------------------------------------------
+            case EXIST -> field + " IS NOT NULL";
+
+            case DOES_NOT_EXIST -> field + " IS NULL";
+
+            // ---------------------------------------------------------------------
+            // Ranges (non-timestamp fields)
+            // ---------------------------------------------------------------------
+            case IS_BETWEEN -> {
+                if (list.size() != 2) {
+                    throw new IllegalArgumentException("IS_BETWEEN requires exactly 2 values");
+                }
+                yield field + " BETWEEN '" + list.get(0) + "' AND '" + list.get(1) + "'";
+            }
+
+            case IS_NOT_BETWEEN -> {
+                if (list.size() != 2) {
+                    throw new IllegalArgumentException("IS_NOT_BETWEEN requires exactly 2 values");
+                }
+                yield field + " NOT BETWEEN '" + list.get(0) + "' AND '" + list.get(1) + "'";
+            }
+
+            case IS_GREATER_THAN ->
+                    field + " > '" + list.get(0) + "'";
+
+            case IS_LESS_THAN_OR_EQUALS ->
+                    field + " <= '" + list.get(0) + "'";
+
+            // ---------------------------------------------------------------------
+            // Starts / ends with
+            // ---------------------------------------------------------------------
+            case START_WITH ->
+                    field + " LIKE '" + list.get(0) + "%'";
+
+            case NOT_START_WITH ->
+                    field + " NOT LIKE '" + list.get(0) + "%'";
+
+            case ENDS_WITH ->
+                    field + " LIKE '%" + list.get(0) + "'";
+
+            case NOT_ENDS_WITH ->
+                    field + " NOT LIKE '%" + list.get(0) + "'";
+
+            // ---------------------------------------------------------------------
+            // Value in multiple fields
+            // ---------------------------------------------------------------------
+            case IS_IN_FIELDS ->
+                    "'" + list.get(0) + "' IN (" + String.join(", ", list) + ")";
+
+            case IS_NOT_IN_FIELDS ->
+                    "'" + list.get(0) + "' NOT IN (" + String.join(", ", list) + ")";
+
+            // ---------------------------------------------------------------------
+            default -> throw new IllegalArgumentException("Unsupported operator: " + f.getOperator());
+        };
+    }
+
+    /**
+     * Joins a list of values into a comma-separated list of quoted literals.
+     * Example: ["a","b"] -> 'a', 'b'
+     */
+    private String joinQuoted(List<String> values) {
+        return values.stream()
+                .map(v -> "'" + v + "'")
+                .collect(Collectors.joining(", "));
+    }
+
+    // -------------------------------------------------------------------------
+    //  AND / OR COMBINATION
+    // -------------------------------------------------------------------------
+
+    /**
+     * Combines AND and OR condition lists into a single SQL expression.
+     * - AND conditions are grouped in parentheses.
+     * - OR conditions are grouped in parentheses.
+     * - If both exist: (AND...) AND (OR...)
+     */
+    private String combineConditions(List<String> ands, List<String> ors) {
+
+        String andPart = ands.isEmpty()
+                ? ""
+                : "(" + String.join(" AND ", ands) + ")";
+
+        String orPart = ors.isEmpty()
+                ? ""
+                : "(" + String.join(" OR ", ors) + ")";
+
+        if (!andPart.isEmpty() && !orPart.isEmpty()) {
+            return andPart + " AND " + orPart;
+        }
+
+        return andPart + orPart;
+    }
+
+    // -------------------------------------------------------------------------
+    //  MERGING WITH BASE SQL
+    // -------------------------------------------------------------------------
+
+    /**
+     * Merges the generated WHERE clause into the base SQL.
+     * - If base SQL already has WHERE, appends "AND <whereClause>".
+     * - Otherwise, appends "WHERE <whereClause>".
+     */
+    private String mergeSql(String sql, String whereClause) {
+        if (whereClause == null || whereClause.isBlank()) {
+            return sql;
+        }
+
+        String normalized = normalizeForSearch(sql);
+
+        // Case 1: SQL already contains WHERE → append AND
+        int whereIndex = normalized.indexOf(" where ");
+        if (whereIndex != -1) {
+            // Find where the WHERE clause ends (before GROUP BY / ORDER BY / LIMIT)
+            int endOfWhere = findEndOfWhereClause(normalized, whereIndex + 7);
+            return sql.substring(0, endOfWhere)
+                    + " AND " + whereClause + " "
+                    + sql.substring(endOfWhere);
+        }
+
+        // Case 2: Insert WHERE after FROM <target>
+        int fromIndex = normalized.indexOf(" from ");
+        if (fromIndex != -1) {
+            int insertPos = findEndOfFromTarget(sql, normalized, fromIndex + 6);
+            return sql.substring(0, insertPos)
+                    + " WHERE " + whereClause + " "
+                    + sql.substring(insertPos);
+        }
+
+        // Case 3: fallback
+        return sql + " WHERE " + whereClause;
+    }
+
+    private int findEndOfFromTarget(String originalSql, String normalizedSql, int start) {
+
+        List<String> keywords = List.of(" group by ", " order by ", " limit ", " having ", " where ");
+
+        int nextKeywordPos = normalizedSql.length();
+
+        for (String kw : keywords) {
+            int idx = normalizedSql.indexOf(kw, start);
+            if (idx != -1 && idx < nextKeywordPos) {
+                nextKeywordPos = idx;
+            }
+        }
+
+        // Convert normalized index back to original index
+        String before = normalizedSql.substring(0, nextKeywordPos);
+        String lastToken = before.trim().substring(before.trim().lastIndexOf(" ") + 1);
+
+        int originalIndex = originalSql.toLowerCase().indexOf(lastToken);
+
+        return originalIndex == -1 ? originalSql.length() : originalIndex + lastToken.length();
+    }
+
+    private int findEndOfWhereClause(String normalized, int start) {
+        List<String> keywords = List.of(" group by ", " order by ", " limit ", " having ");
+
+        int nextKeywordPos = normalized.length();
+
+        for (String kw : keywords) {
+            int idx = normalized.indexOf(kw, start);
+            if (idx != -1 && idx < nextKeywordPos) {
+                nextKeywordPos = idx;
+            }
+        }
+
+        return nextKeywordPos;
+    }
+
+    private List<String> asList(Object value) {
+        if (value == null) {
+            return List.of();
+        }
+        if (value instanceof List<?> list) {
+            return list.stream().map(String::valueOf).toList();
+        }
+        return List.of(String.valueOf(value)); // single value → list of one
+    }
+
+    private String normalizeForSearch(String sql) {
+        return sql
+                .replace("\n", " ")
+                .replace("\r", " ")
+                .replace("\t", " ")
+                .replaceAll(" +", " ")
+                .toLowerCase();
+    }
+}
+