#!/bin/bash
# =============================================================================
# SAP HANA Disk Space Monitoring Script
# Checks disk usage for configured directories with auto-cleanup capability
# =============================================================================

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" &>/dev/null && pwd)"
SCRIPT_NAME="hana_disk"

# Load configuration
source "${SCRIPT_DIR}/hana.conf"
source "${SCRIPT_DIR}/hana_lib.sh"

# Acquire lock
LOCK_FILE=$(acquire_lock "$SCRIPT_NAME")
if [ $? -ne 0 ]; then
    exit 1
fi
trap 'release_lock "$LOCK_FILE"' EXIT

log_message "$SCRIPT_NAME" "Starting disk usage check..."

# Track overall status
ALERT_COUNT=0
TOTAL_DIRS=0
CLEANUP_PERFORMED=0

for dir in "${DIRECTORIES_TO_MONITOR[@]}"; do
    TOTAL_DIRS=$((TOTAL_DIRS + 1))
    
    # Check if directory exists
    if [ ! -d "$dir" ]; then
        log_message "$SCRIPT_NAME" "WARNING: Directory '$dir' not found. Skipping."
        send_notification_if_changed "$SCRIPT_NAME" "disk_dir_not_found_${dir//\//_}" "HANA Disk Warning" "Directory '$dir' not found." "true" "DIR_NOT_FOUND"
        ALERT_COUNT=$((ALERT_COUNT + 1))
        continue
    fi
    
    # Get disk usage percentage
    usage=$(get_disk_usage_percentage "$dir")
    
    if [ -z "$usage" ] || [ "$usage" -eq 0 ]; then
        log_message "$SCRIPT_NAME" "WARNING: Could not determine disk usage for '$dir'. Skipping."
        continue
    fi
    
    log_message "$SCRIPT_NAME" "Directory ${dir} is at ${usage}%"
    
    # Check if usage exceeds threshold
    if [ "$usage" -gt "$DISK_USAGE_THRESHOLD" ]; then
        log_message "$SCRIPT_NAME" "ALERT: ${dir} usage is at ${usage}% which is above the ${DISK_USAGE_THRESHOLD}% threshold."
        
        # Attempt auto-cleanup if enabled
        if [ "$AUTO_CLEANUP_ENABLED" == "true" ]; then
            log_message "$SCRIPT_NAME" "Attempting auto-cleanup for '${dir}'..."
            mount_point=$(get_mount_point "$dir")
            
            if auto_cleanup "$mount_point" "$MIN_FREE_SPACE_AFTER_CLEANUP"; then
                CLEANUP_PERFORMED=$((CLEANUP_PERFORMED + 1))
                new_usage=$(get_disk_usage_percentage "$dir")
                log_message "$SCRIPT_NAME" "After cleanup, ${dir} usage is at ${new_usage}%"
                usage=$new_usage
            else
                log_message "$SCRIPT_NAME" "Auto-cleanup failed or no files to clean for '${dir}'"
            fi
        fi
        
        # Send notification with final usage after cleanup attempt
        send_notification_if_changed "$SCRIPT_NAME" "disk_usage_${dir//\//_}" "HANA Disk" "Disk usage for ${dir} is at ${usage}%." "true" "${usage}%"
        ALERT_COUNT=$((ALERT_COUNT + 1))
    else
        # Send OK notification only if state changed from alert
        send_notification_if_changed "$SCRIPT_NAME" "disk_usage_${dir//\//_}" "HANA Disk" "Disk usage for ${dir} is at ${usage}% (below threshold)." "false" "OK"
    fi
done

# Summary logging
log_message "$SCRIPT_NAME" "Disk check complete. Total: ${TOTAL_DIRS} dirs, ${ALERT_COUNT} alerts, ${CLEANUP_PERFORMED} cleanups performed."

# Exit with status based on alerts
if [ "$ALERT_COUNT" -gt 0 ]; then
    exit 1
fi
exit 0