#!/bin/bash

# Enhanced Backup Log Monitor
# Provides real-time monitoring and analysis of backup operations

set -e

# Color codes for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
CYAN='\033[0;36m'
PURPLE='\033[0;35m'
NC='\033[0m' # No Color

SCRIPT_DIR="$(dirname "$(readlink -f "$0")")"
LOG_DIR="$SCRIPT_DIR/logs"
REPORT_DIR="$LOG_DIR/reports"
HOSTNAME=$(hostname)

# Ensure directories exist
mkdir -p "$LOG_DIR" "$REPORT_DIR"

# Backup service tags for monitoring
BACKUP_TAGS=("plex-backup" "backup-move" "plex-validation" "immich-backup" "plex-report" "crontab-backup")

log_message() {
    echo -e "$(date '+%H:%M:%S') $1"
}

log_error() {
    log_message "${RED}ERROR: $1${NC}"
}

log_success() {
    log_message "${GREEN}SUCCESS: $1${NC}"
}

log_warning() {
    log_message "${YELLOW}WARNING: $1${NC}"
}

log_info() {
    log_message "${BLUE}INFO: $1${NC}"
}

monitor_realtime() {
    local tags_filter=""
    for tag in "${BACKUP_TAGS[@]}"; do
        tags_filter="$tags_filter -t $tag"
    done
    
    log_info "Starting real-time monitoring of backup logs"
    log_info "Press Ctrl+C to stop monitoring"
    echo
    
    sudo journalctl -f $tags_filter --no-hostname --output=short-iso | while read -r line; do
        # Color code different log levels and services
        if [[ "$line" =~ ERROR ]]; then
            echo -e "${RED}$line${NC}"
        elif [[ "$line" =~ SUCCESS ]]; then
            echo -e "${GREEN}$line${NC}"
        elif [[ "$line" =~ WARNING ]]; then
            echo -e "${YELLOW}$line${NC}"
        elif [[ "$line" =~ plex-backup ]]; then
            echo -e "${BLUE}$line${NC}"
        elif [[ "$line" =~ backup-move ]]; then
            echo -e "${CYAN}$line${NC}"
        elif [[ "$line" =~ plex-validation ]]; then
            echo -e "${PURPLE}$line${NC}"
        else
            echo "$line"
        fi
    done
}

show_recent_logs() {
    local hours="${1:-24}"
    local service="${2:-all}"
    
    log_info "Showing logs from the last $hours hours"
    
    local tags_filter=""
    if [ "$service" = "all" ]; then
        for tag in "${BACKUP_TAGS[@]}"; do
            tags_filter="$tags_filter -t $tag"
        done
    else
        tags_filter="-t $service"
    fi
    
    echo
    sudo journalctl --since "${hours} hours ago" $tags_filter --no-hostname --output=short-iso | \
    while read -r line; do
        # Color code the output
        if [[ "$line" =~ ERROR ]]; then
            echo -e "${RED}$line${NC}"
        elif [[ "$line" =~ SUCCESS ]]; then
            echo -e "${GREEN}$line${NC}"
        elif [[ "$line" =~ WARNING ]]; then
            echo -e "${YELLOW}$line${NC}"
        else
            echo "$line"
        fi
    done
}

show_error_summary() {
    local days="${1:-7}"
    
    log_info "Error summary for the last $days days"
    echo
    
    local error_file="/tmp/backup_errors_$$.tmp"
    
    for tag in "${BACKUP_TAGS[@]}"; do
        local error_count=$(sudo journalctl --since "${days} days ago" -t "$tag" --grep="ERROR" --output=cat | wc -l)
        if [ "$error_count" -gt 0 ]; then
            echo -e "${RED}$tag: $error_count errors${NC}"
            sudo journalctl --since "${days} days ago" -t "$tag" --grep="ERROR" --output=short-iso | head -5
            echo
        else
            echo -e "${GREEN}$tag: No errors${NC}"
        fi
    done
}

generate_backup_report() {
    local days="${1:-7}"
    local report_file="$REPORT_DIR/backup-report-$(date +%Y%m%d_%H%M%S).txt"
    
    log_info "Generating comprehensive backup report for the last $days days"
    log_info "Report will be saved to: $report_file"
    
    {
        echo "=== BACKUP SYSTEM REPORT ==="
        echo "Generated: $(date)"
        echo "Period: Last $days days"
        echo "System: $(uname -n)"
        echo
        
        for tag in "${BACKUP_TAGS[@]}"; do
            echo "=== $tag ===" 
            
            # Count entries
            local total_entries=$(sudo journalctl --since "${days} days ago" -t "$tag" --output=cat | wc -l)
            local error_count=$(sudo journalctl --since "${days} days ago" -t "$tag" --grep="ERROR" --output=cat | wc -l)
            local success_count=$(sudo journalctl --since "${days} days ago" -t "$tag" --grep="SUCCESS" --output=cat | wc -l)
            
            echo "Total log entries: $total_entries"
            echo "Errors: $error_count"
            echo "Successes: $success_count"
            
            if [ "$error_count" -gt 0 ]; then
                echo
                echo "Recent errors:"
                sudo journalctl --since "${days} days ago" -t "$tag" --grep="ERROR" --output=short-iso | head -10
            fi
            
            echo
            echo "Recent activity:"
            sudo journalctl --since "${days} days ago" -t "$tag" --output=short-iso | tail -5
            echo
            echo "----------------------------------------"
            echo
        done
        
        # System resource usage during backups
        echo "=== SYSTEM ANALYSIS ==="
        echo "Disk usage in backup directories:"
        if [ -d "/mnt/share/media/backups" ]; then
            du -sh /mnt/share/media/backups/* 2>/dev/null || echo "No backup directories found"
        fi
        echo
        
        # Cron job status
        echo "Active cron jobs related to backups:"
        sudo crontab -l 2>/dev/null | grep -E "(backup|plex|immich)" || echo "No backup-related cron jobs found"
        echo
        
    } > "$report_file"
    
    log_success "Report generated: $report_file"
    
    # Show summary
    echo
    log_info "Report Summary:"
    grep -E "(Total log entries|Errors|Successes):" "$report_file" | while read -r line; do
        if [[ "$line" =~ Errors:.*[1-9] ]]; then
            echo -e "${RED}$line${NC}"
        else
            echo -e "${GREEN}$line${NC}"
        fi
    done
}

check_backup_health() {
    log_info "Checking backup system health for $HOSTNAME"
    echo
    
    local health_score=100
    local issues=()
    
    # Check if backup scripts exist
    local backup_scripts=(
        "/home/acedanger/shell/backup-plex.sh"
        "/home/acedanger/shell/move-backups.sh"
        "/home/acedanger/shell/validate-plex-backups.sh"
        "/home/acedanger/shell/crontab/crontab-backup-system.sh"
    )
    
    for script in "${backup_scripts[@]}"; do
        if [ ! -f "$script" ]; then
            issues+=("Missing script: $script")
            ((health_score -= 20))
        elif [ ! -x "$script" ]; then
            issues+=("Script not executable: $script")
            ((health_score -= 10))
        fi
    done
    
    # Check if backup directories exist
    local backup_dirs=(
        "/mnt/share/media/backups/plex"
        "/mnt/share/media/backups/docker-data"
        "/mnt/share/media/backups/immich"
    )
    
    for dir in "${backup_dirs[@]}"; do
        if [ ! -d "$dir" ]; then
            issues+=("Missing backup directory: $dir")
            ((health_score -= 15))
        fi
    done
    
    # Check crontab backup system structure
    local crontab_backup_dir="$SCRIPT_DIR/crontab-backups/$HOSTNAME"
    if [ ! -d "$crontab_backup_dir" ]; then
        issues+=("Missing crontab backup directory for $HOSTNAME: $crontab_backup_dir")
        ((health_score -= 10))
    fi
    
    # Check recent backup activity
    local recent_activity=false
    for tag in "${BACKUP_TAGS[@]}"; do
        if sudo journalctl --since "24 hours ago" -t "$tag" --output=cat | grep -q .; then
            recent_activity=true
            break
        fi
    done
    
    if [ "$recent_activity" = false ]; then
        issues+=("No backup activity in the last 24 hours")
        ((health_score -= 25))
    fi
    
    # Check for recent errors
    local recent_errors=0
    for tag in "${BACKUP_TAGS[@]}"; do
        local error_count=$(sudo journalctl --since "24 hours ago" -t "$tag" --grep="ERROR" --output=cat | wc -l)
        ((recent_errors += error_count))
    done
    
    if [ "$recent_errors" -gt 0 ]; then
        issues+=("$recent_errors errors in the last 24 hours")
        ((health_score -= $((recent_errors * 5))))
    fi
    
    # Ensure health score doesn't go below 0
    if [ "$health_score" -lt 0 ]; then
        health_score=0
    fi
    
    # Display results
    if [ "$health_score" -ge 90 ]; then
        echo -e "${GREEN}Backup System Health ($HOSTNAME): ${health_score}% - EXCELLENT${NC}"
    elif [ "$health_score" -ge 70 ]; then
        echo -e "${YELLOW}Backup System Health ($HOSTNAME): ${health_score}% - GOOD${NC}"
    elif [ "$health_score" -ge 50 ]; then
        echo -e "${YELLOW}Backup System Health ($HOSTNAME): ${health_score}% - FAIR${NC}"
    else
        echo -e "${RED}Backup System Health ($HOSTNAME): ${health_score}% - POOR${NC}"
    fi
    
    if [ ${#issues[@]} -gt 0 ]; then
        echo
        log_warning "Issues found:"
        for issue in "${issues[@]}"; do
            echo -e "  ${RED}• $issue${NC}"
        done
        
        echo
        log_info "Recommended actions:"
        echo "  • Run: ./manage-enhanced-crontab.sh verify"
        echo "  • Check system logs: sudo journalctl -xe"
        echo "  • Verify backup directories are mounted and accessible"
        echo "  • Run: ./crontab-backup-system.sh status"
    fi
}

show_service_status() {
    log_info "Backup Service Status Overview"
    echo
    
    printf "%-20s %-15s %-20s %-30s\n" "Service" "Status" "Last Activity" "Last Message"
    printf "%-20s %-15s %-20s %-30s\n" "-------" "------" "-------------" "------------"
    
    for tag in "${BACKUP_TAGS[@]}"; do
        local last_entry=$(sudo journalctl -t "$tag" --output=short-iso -n 1 2>/dev/null | tail -1)
        
        if [ -n "$last_entry" ]; then
            local timestamp=$(echo "$last_entry" | cut -d' ' -f1-2)
            local message=$(echo "$last_entry" | cut -d' ' -f4- | cut -c1-30)
            
            # Check if it's recent (within 48 hours)
            local entry_time=$(date -d "$timestamp" +%s 2>/dev/null || echo "0")
            local current_time=$(date +%s)
            local hours_diff=$(( (current_time - entry_time) / 3600 ))
            
            local status
            if [ "$hours_diff" -le 24 ]; then
                status="${GREEN}Active${NC}"
            elif [ "$hours_diff" -le 48 ]; then
                status="${YELLOW}Recent${NC}"
            else
                status="${RED}Stale${NC}"
            fi
            
            printf "%-20s %-25s %-20s %-30s\n" "$tag" "$status" "$timestamp" "$message"
        else
            printf "%-20s %-25s %-20s %-30s\n" "$tag" "${RED}No logs${NC}" "Never" "No activity found"
        fi
    done
}

show_usage() {
    echo -e "${PURPLE}Enhanced Backup Log Monitor${NC}"
    echo
    echo "Usage: $0 [COMMAND] [OPTIONS]"
    echo
    echo "Commands:"
    echo "  monitor                 Real-time monitoring of all backup logs"
    echo "  recent [HOURS] [SERVICE] Show recent logs (default: 24 hours, all services)"
    echo "  errors [DAYS]           Show error summary (default: 7 days)"
    echo "  report [DAYS]           Generate comprehensive report (default: 7 days)"
    echo "  health                  Check backup system health"
    echo "  status                  Show service status overview"
    echo "  help                    Show this help message"
    echo
    echo "Services:"
    for tag in "${BACKUP_TAGS[@]}"; do
        echo "  - $tag"
    done
    echo
    echo "Examples:"
    echo "  $0 monitor"
    echo "  $0 recent 12 plex-backup"
    echo "  $0 errors 3"
    echo "  $0 report 14"
    echo
}

# Main command handling
case "${1:-help}" in
    monitor)
        monitor_realtime
        ;;
    recent)
        show_recent_logs "$2" "$3"
        ;;
    errors)
        show_error_summary "$2"
        ;;
    report)
        generate_backup_report "$2"
        ;;
    health)
        check_backup_health
        ;;
    status)
        show_service_status
        ;;
    help|*)
        show_usage
        ;;
esac