#!/bin/bash

# This script keeps only one backup file per month for 2023
# It will keep the first backup of each month (usually the 1st day at midnight)
# and delete all other 2023 backups

# Create a deletion plan file
deletion_plan="backup_deletion_plan_$(date +%Y%m%d_%H%M%S).txt"
echo "Backup Deletion Plan - Created $(date)" > "$deletion_plan"
echo "----------------------------------------" >> "$deletion_plan"
echo "The following 2023 backup files will be kept:" >> "$deletion_plan"

# Create an associative array to track which files to keep
declare -A keep_files

# Find all 2023 backup files and identify one per month to keep
for file in backup_2023_*.sql.gz; do
    # Extract month from filename (position 13-14 in the filename)
    month=${file:13:2}

    # If we haven't marked a file to keep for this month yet, keep this one
    if [[ -z ${keep_files[$month]} ]]; then
        keep_files[$month]=$file
        echo "Keeping $file as the representative backup for month $month"
        echo "KEEP: $file" >> "$deletion_plan"
    fi
done

# Add a section for files to be deleted
echo "" >> "$deletion_plan"
echo "The following 2023 backup files will be deleted:" >> "$deletion_plan"

# Now identify all 2023 backup files for deletion (without deleting yet)
delete_count=0
for file in backup_2023_*.sql.gz; do
    # Check if this file is in our keep list
    keep=0
    for keep_file in "${keep_files[@]}"; do
        if [[ "$file" == "$keep_file" ]]; then
            keep=1
            break
        fi
    done

    # If not in keep list, mark for deletion
    if [[ $keep -eq 0 ]]; then
        echo "Marking for deletion: $file"
        echo "DELETE: $file" >> "$deletion_plan"
        delete_count=$((delete_count+1))
    fi
done

# Add summary to deletion plan
echo "" >> "$deletion_plan"
echo "----------------------------------------" >> "$deletion_plan"
echo "Summary: Will keep ${#keep_files[@]} files and delete $delete_count files" >> "$deletion_plan"
echo "To execute this plan, run: ./execute_deletion_plan.sh" >> "$deletion_plan"

# Create the execution script
cat > execute_deletion_plan.sh << 'EOF'
#!/bin/bash

# Check if deletion plan file is provided
if [ $# -ne 1 ]; then
    echo "Usage: $0 <deletion_plan_file>"
    exit 1
fi

plan_file="$1"

# Check if the file exists
if [ ! -f "$plan_file" ]; then
    echo "Error: Deletion plan file not found: $plan_file"
    exit 1
fi

echo "Executing deletion plan from: $plan_file"
echo "----------------------------------------"

# Process the deletion plan
while IFS= read -r line; do
    if [[ $line == DELETE:* ]]; then
        file="${line#DELETE: }"
        if [ -f "$file" ]; then
            echo "Deleting: $file"
            rm "$file"
        else
            echo "Warning: File not found: $file"
        fi
    fi
done < "$plan_file"

echo "----------------------------------------"
echo "Deletion plan execution completed."
EOF

chmod +x execute_deletion_plan.sh

echo "Deletion plan created: $deletion_plan"
echo "Review the plan and then execute it with: ./execute_deletion_plan.sh $deletion_plan"