# NEW SAVE ORDER IMPLEMENTATION

## Overview
Updated the voter import system to implement a new save order: **Streets → Booth → Voters** instead of the previous Booth → Streets → Voters flow.

## Changes Made

### 1. Modified ProcessVoterImageBatch.php
- **extractAndPersistBoothAndStreets()** method updated to implement new save order:
  1. **Step 1**: Create streets first without booth_id (independent street records)
  2. **Step 2**: Create booth with streets array containing street IDs
  3. **Step 3**: Update streets to link them back to booth (for relational integrity)

### 2. Updated Street Model
- Made booth_id nullable to support independent street creation
- Streets can now exist without being immediately linked to a booth

### 3. Enhanced ensureStreetExists() Method  
- Updated to work with new save order where streets may exist without booth_id initially
- Prioritizes booth_id matches but falls back to name-only lookups
- Updates booth_id when needed

## New Data Flow

### Before (Old Order)
```
1. Create/Find Booth (booth_number, booth_address)
2. Create Streets linked to booth_id 
3. Create Voters linked to booth_id and street_id
```

### After (New Order)
```
1. Create Streets (street_name, booth_id=null, is_deleted=false)
2. Create Booth (booth_number, booth_address, streets=[1,2,3,4,5...])  
3. Update Streets to link back to booth_id (optional - for relational integrity)
4. Create Voters linked to booth_id and street_id
```

## Database Structure

### Streets Table
- `id` (primary key)
- `street_name` (varchar)
- `booth_id` (nullable foreign key) 
- `is_deleted` (boolean)

### Booths Table  
- `id` (primary key)
- `booth_number` (varchar)
- `booth_address` (text)
- `streets` (JSON array of street IDs)
- `is_deleted` (boolean)

### Voters Table
- Links to both `booth_id` and `street_id` for full relational integrity

## Benefits

1. **Independent Street Management**: Streets can be created and managed independently
2. **Flexible Relationships**: Booth maintains array of street IDs for easy querying
3. **Backward Compatibility**: Still maintains foreign key relationships for existing queries
4. **Data Integrity**: Dual referencing (booth.streets array + street.booth_id) ensures consistency

## Testing Results

✅ **Verified Working**:
- 9 streets created independently (booth_id = null initially)
- 1 booth created with streets array: [1,2,3,4,5,6,7,8,9]  
- Streets updated to link back to booth_id: 1
- Full relational integrity maintained

## Example Output
```
Streets: 9
  - ID: 1 | Name: MURUGAN KOIL STREET | Booth ID: 1
  - ID: 2 | Name: SENGENIAMMAN KOIL STREET | Booth ID: 1
  [... 7 more streets ...]

Booths: 1
  - ID: 1 | Number: 1
  - Streets Array: [1,2,3,4,5,6,7,8,9]
```

## Usage

The new save order is now active in `ProcessVoterImageBatch.php`. When processing booth_info.png files:

1. Streets are extracted and created first
2. Booth is created with the array of street IDs
3. Voter processing continues with full booth and street context available

This maintains all existing functionality while providing the requested save order: **Streets → Booth → Voters**.