#!/bin/bash

# Phase 1 Database Cleanup - Remove Empty Tables Only
# This script safely removes tables with 0 rows and no API usage

echo "=== Tilbudgivern Database Cleanup - Phase 1 ==="
echo "Removing empty tables with no API usage..."
echo

# Database connection details
DB_HOST="localhost"
DB_USER="tilbudgivern_service"
DB_PASS="REDACTED_PASSWORD"
DB_NAME="tilbudgivern"

# Function to check if table exists and is empty
check_table() {
    local table_name=$1
    echo "Checking table: $table_name"
    
    # Check if table exists
    exists=$(mysql -h"$DB_HOST" -u"$DB_USER" -p"$DB_PASS" "$DB_NAME" -e "SHOW TABLES LIKE '$table_name';" 2>/dev/null | grep -c "$table_name")
    
    if [ "$exists" -eq 0 ]; then
        echo "  ❌ Table $table_name does not exist"
        return 1
    fi
    
    # Check row count
    row_count=$(mysql -h"$DB_HOST" -u"$DB_USER" -p"$DB_PASS" "$DB_NAME" -e "SELECT COUNT(*) FROM $table_name;" 2>/dev/null | tail -n 1)
    
    if [ "$row_count" -eq 0 ]; then
        echo "  ✅ Table $table_name is empty ($row_count rows)"
        return 0
    else
        echo "  ⚠️  Table $table_name has $row_count rows - SKIPPING"
        return 1
    fi
}

# Function to drop table safely
drop_table() {
    local table_name=$1
    echo "Dropping table: $table_name"
    
    result=$(mysql -h"$DB_HOST" -u"$DB_USER" -p"$DB_PASS" "$DB_NAME" -e "DROP TABLE IF EXISTS $table_name;" 2>&1)
    
    if [ $? -eq 0 ]; then
        echo "  ✅ Successfully dropped $table_name"
    else
        echo "  ❌ Failed to drop $table_name: $result"
    fi
}

# Create backup timestamp
backup_timestamp=$(date +"%Y%m%d_%H%M%S")
echo "Creating backup before cleanup..."
mysqldump -h"$DB_HOST" -u"$DB_USER" -p"$DB_PASS" "$DB_NAME" > "tilbudgivern_backup_before_cleanup_$backup_timestamp.sql"

if [ $? -eq 0 ]; then
    echo "✅ Backup created: tilbudgivern_backup_before_cleanup_$backup_timestamp.sql"
    echo
else
    echo "❌ Backup failed! Aborting cleanup."
    exit 1
fi

# Phase 1: Remove only empty tables (safest cleanup)
echo "=== Phase 1: Removing Empty Tables ==="
echo

tables_to_remove=(
    "bygma_materials_cache"
    "quote_items" 
    "quote_feedback"
    "quote_pricing_history"
    "recent_material_prices"
)

removed_count=0
skipped_count=0

for table in "${tables_to_remove[@]}"; do
    if check_table "$table"; then
        drop_table "$table"
        ((removed_count++))
    else
        ((skipped_count++))
    fi
    echo
done

echo "=== Cleanup Summary ==="
echo "Tables removed: $removed_count"
echo "Tables skipped: $skipped_count"
echo "Backup file: tilbudgivern_backup_before_cleanup_$backup_timestamp.sql"
echo

# Verify remaining table count
echo "=== Final Table Count ==="
final_count=$(mysql -h"$DB_HOST" -u"$DB_USER" -p"$DB_PASS" "$DB_NAME" -e "SHOW TABLES;" 2>/dev/null | wc -l)
((final_count--)) # Subtract header row

echo "Remaining tables: $final_count"
echo

echo "✅ Phase 1 cleanup completed successfully!"
echo "Next steps: Review results and consider Phase 2 (legacy tables) if needed."