# Config 4: Deep Nesting & Complex Structures

## Scenario
**Corner case testing** untuk validasi parser dengan **deep nesting** (5+ levels) dan **complex nested structures** seperti nested arrays dan objects dalam berbagai kombinasi.

## Use Case
Configuration dengan hierarchical structure yang kompleks, seperti routing rules dengan nested conditions dan transformations.

---

## Input: CONFIG4.yaml

```yaml
deepNested:
  level1:
    level2:
      level3:
        level4:
          level5:
            finalValue: reached_bottom
            deepArray:
              - item1
              - item2
  complexMapping:
    rules:
      - condition: status == SUCCESS
        action: PROCEED
        mapping:
          sourceField: response.data.id
          targetField: output.transactionId
          transformation: UPPERCASE
        fallback:
      - condition: status == FAILED
        action: RETRY
        mapping:
          sourceField: response.error.code
          targetField: output.errorCode
        retryConfig:
          maxAttempts: 3
          backoffMs: 1000
      - condition: status == TIMEOUT
        action: CANCEL
        notification:
          - email
          - sms
          - webhook
  metadata:
    version: 2.1.0
    author: ACE Team
    tags:
      - production
      - critical
      - payment
```

---

## Output: hasilParseConfig4.json

```json
{
  "deepNested": {
    "level1": {
      "level2": {
        "level3": {
          "level4": {
            "level5": {
              "finalValue": "reached_bottom",
              "deepArray": ["item1", "item2"]
            }
          }
        }
      }
    },
    "complexMapping": {
      "rules": [
        {
          "condition": "status == SUCCESS",
          "action": "PROCEED",
          "mapping": {
            "sourceField": "response.data.id",
            "targetField": "output.transactionId",
            "transformation": "UPPERCASE"
          },
          "fallback": ""
        },
        {
          "condition": "status == FAILED",
          "action": "RETRY",
          "mapping": {
            "sourceField": "response.error.code",
            "targetField": "output.errorCode"
          },
          "retryConfig": {
            "maxAttempts": "3",
            "backoffMs": "1000"
          }
        },
        {
          "condition": "status == TIMEOUT",
          "action": "CANCEL",
          "notification": ["email", "sms", "webhook"]
        }
      ]
    },
    "metadata": {
      "version": "2.1.0",
      "author": "ACE Team",
      "tags": ["production", "critical", "payment"]
    }
  }
}
```

---

## ESQL Usage

```esql
DECLARE config REFERENCE TO Environment.Variables;
DECLARE success BOOLEAN;

CALL ACE_LIB.getConfig(
    'COMPLEX_CONFIG',
    'deepNested',
    '/path/to/CONFIG4.yaml',
    '600',
    config
) INTO success;

IF success THEN
    -- Access deep nested value (5 levels)
    DECLARE deepValue CHARACTER 
        config.level1.level2.level3.level4.level5.finalValue;
    -- Result: "reached_bottom"
    
    -- Access array in deep nested object
    DECLARE deepArrayItem CHARACTER 
        config.level1.level2.level3.level4.level5.deepArray[1];
    -- Result: "item1"
    
    -- Process complex rules array
    DECLARE ruleRef REFERENCE TO config.complexMapping.rules[1];
    WHILE LASTMOVE(ruleRef) DO
        DECLARE condition CHARACTER ruleRef.condition;
        DECLARE action CHARACTER ruleRef.action;
        
        -- Check for nested mapping object
        IF ruleRef.mapping IS NOT NULL THEN
            DECLARE sourceField CHARACTER ruleRef.mapping.sourceField;
            DECLARE targetField CHARACTER ruleRef.mapping.targetField;
        END IF;
        
        -- Check for nested retryConfig object
        IF ruleRef.retryConfig IS NOT NULL THEN
            DECLARE maxRetries CHARACTER ruleRef.retryConfig.maxAttempts;
        END IF;
        
        -- Check for nested notification array
        DECLARE notifRef REFERENCE TO ruleRef.notification[1];
        IF LASTMOVE(notifRef) THEN
            WHILE LASTMOVE(notifRef) DO
                DECLARE channel CHARACTER notifRef;
                -- "email", "sms", "webhook"
                MOVE notifRef NEXTSIBLING;
            END WHILE;
        END IF;
        
        MOVE ruleRef NEXTSIBLING;
    END WHILE;
END IF;
```

---

## Key Features Tested

✅ Deep nesting hingga 5+ levels  
✅ Arrays dalam deep nested objects  
✅ Array of complex objects  
✅ Nested objects dalam array items (`mapping`, `retryConfig`)  
✅ Nested arrays dalam array items (`notification`)  
✅ Multiple nested structures dalam satu config

---

## Important Notes

- Parser support nesting unlimited depth (limited by memory)
- Nested objects/arrays dalam list items harus properly indented
- Properties dalam nested object tetap accessible dengan dot notation
- Complex navigation path tetap valid di ESQL

---

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