#!/bin/bash

# Plex Backup System Monitoring Dashboard
# Provides real-time status and health monitoring for the enhanced backup system

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'
MAGENTA='\033[0;35m'
NC='\033[0m' # No Color

# Configuration
SCRIPT_DIR="$(dirname "$(readlink -f "$0")")"
BACKUP_ROOT="/mnt/share/media/backups/plex"
LOG_ROOT="/mnt/share/media/backups/logs"
JSON_LOG_FILE="$SCRIPT_DIR/logs/plex-backup.json"
PERFORMANCE_LOG_FILE="$SCRIPT_DIR/logs/plex-backup-performance.json"

# Display mode
WATCH_MODE=false
REFRESH_INTERVAL=5

# Parse command line arguments
while [[ $# -gt 0 ]]; do
    case $1 in
        --watch)
            WATCH_MODE=true
            shift
            ;;
        --interval=*)
            REFRESH_INTERVAL="${1#*=}"
            shift
            ;;
        -h|--help)
            echo "Usage: $0 [OPTIONS]"
            echo "Options:"
            echo "  --watch          Continuous monitoring mode (refresh every 5 seconds)"
            echo "  --interval=N     Set refresh interval for watch mode (seconds)"
            echo "  -h, --help       Show this help message"
            exit 0
            ;;
        *)
            echo "Unknown option: $1"
            echo "Use --help for usage information"
            exit 1
            ;;
    esac
done

# Utility functions
log_status() {
    local status="$1"
    local message="$2"
    case "$status" in
        "OK") echo -e "${GREEN}✓${NC} $message" ;;
        "WARN") echo -e "${YELLOW}⚠${NC} $message" ;;
        "ERROR") echo -e "${RED}✗${NC} $message" ;;
        "INFO") echo -e "${BLUE}ℹ${NC} $message" ;;
    esac
}

# Clear screen for watch mode
clear_screen() {
    if [ "$WATCH_MODE" = true ]; then
        clear
    fi
}

# Header display
show_header() {
    echo -e "${CYAN}╔══════════════════════════════════════════════════════════════════════════════╗${NC}"
    echo -e "${CYAN}║${NC}                       ${MAGENTA}PLEX BACKUP SYSTEM DASHBOARD${NC}                        ${CYAN}║${NC}"
    echo -e "${CYAN}║${NC}                           $(date '+%Y-%m-%d %H:%M:%S')                            ${CYAN}║${NC}"
    echo -e "${CYAN}╚══════════════════════════════════════════════════════════════════════════════╝${NC}"
    echo
}

# System status check
check_system_status() {
    echo -e "${BLUE}📊 SYSTEM STATUS${NC}"
    echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
    
    # Check Plex service
    if systemctl is-active --quiet plexmediaserver; then
        log_status "OK" "Plex Media Server is running"
    else
        log_status "ERROR" "Plex Media Server is not running"
    fi
    
    # Check backup script
    if [ -f "$SCRIPT_DIR/backup-plex.sh" ]; then
        log_status "OK" "Backup script is present"
    else
        log_status "ERROR" "Backup script not found"
    fi
    
    # Check directories
    if [ -d "$BACKUP_ROOT" ]; then
        log_status "OK" "Backup directory exists"
    else
        log_status "ERROR" "Backup directory missing: $BACKUP_ROOT"
    fi
    
    if [ -d "$LOG_ROOT" ]; then
        log_status "OK" "Log directory exists"
    else
        log_status "WARN" "Log directory missing: $LOG_ROOT"
    fi
    
    # Check dependencies
    for cmd in jq sqlite3 curl; do
        if command -v "$cmd" >/dev/null 2>&1; then
            log_status "OK" "$cmd is available"
        else
            log_status "WARN" "$cmd is not installed"
        fi
    done
    
    echo
}

# Backup status
check_backup_status() {
    echo -e "${BLUE}💾 BACKUP STATUS${NC}"
    echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
    
    # Count total backups
    local backup_count=0
    if [ -d "$BACKUP_ROOT" ]; then
        backup_count=$(find "$BACKUP_ROOT" -maxdepth 1 -type d -name "????????" 2>/dev/null | wc -l)
    fi
    
    if [ "$backup_count" -gt 0 ]; then
        log_status "OK" "Total backups: $backup_count"
        
        # Find latest backup
        local latest_backup=$(find "$BACKUP_ROOT" -maxdepth 1 -type d -name "????????" 2>/dev/null | sort | tail -1)
        if [ -n "$latest_backup" ]; then
            local backup_date=$(basename "$latest_backup")
            local readable_date=$(date -d "${backup_date:0:4}-${backup_date:4:2}-${backup_date:6:2}" '+%B %d, %Y' 2>/dev/null || echo "Invalid date")
            local backup_age_days=$(( ($(date +%s) - $(date -d "${backup_date:0:4}-${backup_date:4:2}-${backup_date:6:2}" +%s 2>/dev/null || echo "0")) / 86400 ))
            
            if [ "$backup_age_days" -le 1 ]; then
                log_status "OK" "Latest backup: $readable_date ($backup_age_days days ago)"
            elif [ "$backup_age_days" -le 7 ]; then
                log_status "WARN" "Latest backup: $readable_date ($backup_age_days days ago)"
            else
                log_status "ERROR" "Latest backup: $readable_date ($backup_age_days days ago)"
            fi
            
            # Check backup size
            local backup_size=$(du -sh "$latest_backup" 2>/dev/null | cut -f1)
            log_status "INFO" "Latest backup size: $backup_size"
            
            # Check backup contents
            local file_count=$(ls -1 "$latest_backup" 2>/dev/null | wc -l)
            log_status "INFO" "Files in latest backup: $file_count"
        fi
    else
        log_status "WARN" "No backups found"
    fi
    
    # Disk usage
    if [ -d "$BACKUP_ROOT" ]; then
        local total_backup_size=$(du -sh "$BACKUP_ROOT" 2>/dev/null | cut -f1)
        local available_space=$(df -h "$BACKUP_ROOT" 2>/dev/null | awk 'NR==2 {print $4}')
        local used_percentage=$(df "$BACKUP_ROOT" 2>/dev/null | awk 'NR==2 {print $5}' | sed 's/%//')
        
        log_status "INFO" "Total backup storage: $total_backup_size"
        log_status "INFO" "Available space: $available_space"
        
        if [ -n "$used_percentage" ]; then
            if [ "$used_percentage" -lt 80 ]; then
                log_status "OK" "Disk usage: $used_percentage%"
            elif [ "$used_percentage" -lt 90 ]; then
                log_status "WARN" "Disk usage: $used_percentage%"
            else
                log_status "ERROR" "Disk usage: $used_percentage% (Critical)"
            fi
        fi
    fi
    
    echo
}

# Performance metrics
show_performance_metrics() {
    echo -e "${BLUE}⚡ PERFORMANCE METRICS${NC}"
    echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
    
    if [ -f "$PERFORMANCE_LOG_FILE" ]; then
        log_status "OK" "Performance log found"
        
        # Recent operations
        local recent_count=$(jq length "$PERFORMANCE_LOG_FILE" 2>/dev/null || echo "0")
        log_status "INFO" "Total logged operations: $recent_count"
        
        if [ "$recent_count" -gt 0 ]; then
            # Average times for different operations
            local avg_backup=$(jq '[.[] | select(.operation == "full_backup") | .duration_seconds] | if length > 0 then add/length else 0 end' "$PERFORMANCE_LOG_FILE" 2>/dev/null || echo "0")
            local avg_verification=$(jq '[.[] | select(.operation == "verification") | .duration_seconds] | if length > 0 then add/length else 0 end' "$PERFORMANCE_LOG_FILE" 2>/dev/null || echo "0")
            local avg_service_stop=$(jq '[.[] | select(.operation == "service_stop") | .duration_seconds] | if length > 0 then add/length else 0 end' "$PERFORMANCE_LOG_FILE" 2>/dev/null || echo "0")
            local avg_service_start=$(jq '[.[] | select(.operation == "service_start") | .duration_seconds] | if length > 0 then add/length else 0 end' "$PERFORMANCE_LOG_FILE" 2>/dev/null || echo "0")
            
            if [ "$avg_backup" != "0" ] && [ "$avg_backup" != "null" ]; then
                log_status "INFO" "Average backup time: ${avg_backup}s"
            fi
            if [ "$avg_verification" != "0" ] && [ "$avg_verification" != "null" ]; then
                log_status "INFO" "Average verification time: ${avg_verification}s"
            fi
            if [ "$avg_service_stop" != "0" ] && [ "$avg_service_stop" != "null" ]; then
                log_status "INFO" "Average service stop time: ${avg_service_stop}s"
            fi
            if [ "$avg_service_start" != "0" ] && [ "$avg_service_start" != "null" ]; then
                log_status "INFO" "Average service start time: ${avg_service_start}s"
            fi
            
            # Last 3 operations
            echo -e "${YELLOW}Recent Operations:${NC}"
            jq -r '.[-3:] | .[] | "  \(.timestamp): \(.operation) (\(.duration_seconds)s)"' "$PERFORMANCE_LOG_FILE" 2>/dev/null | sed 's/T/ /' | sed 's/+.*$//' || echo "  No recent operations"
        fi
    else
        log_status "WARN" "Performance log not found (no backups run yet)"
    fi
    
    echo
}

# Recent activity
show_recent_activity() {
    echo -e "${BLUE}📋 RECENT ACTIVITY${NC}"
    echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
    
    # Check JSON log for last backup times
    if [ -f "$JSON_LOG_FILE" ]; then
        log_status "OK" "Backup tracking log found"
        
        local file_count=$(jq 'length' "$JSON_LOG_FILE" 2>/dev/null || echo "0")
        log_status "INFO" "Tracked files: $file_count"
        
        if [ "$file_count" -gt 0 ]; then
            echo -e "${YELLOW}Last Backup Times:${NC}"
            jq -r 'to_entries | .[] | "  \(.key | split("/") | .[-1]): \(.value | strftime("%Y-%m-%d %H:%M:%S"))"' "$JSON_LOG_FILE" 2>/dev/null | head -5
        fi
    else
        log_status "WARN" "Backup tracking log not found"
    fi
    
    # Check recent log files
    if [ -d "$LOG_ROOT" ]; then
        local recent_log=$(find "$LOG_ROOT" -name "plex-backup-*.log" -type f 2>/dev/null | sort | tail -1)
        if [ -n "$recent_log" ]; then
            local log_date=$(basename "$recent_log" | sed 's/plex-backup-//' | sed 's/.log//')
            log_status "INFO" "Most recent log: $log_date"
            
            # Check for errors in recent log
            local error_count=$(grep -c "ERROR:" "$recent_log" 2>/dev/null || echo "0")
            local warning_count=$(grep -c "WARNING:" "$recent_log" 2>/dev/null || echo "0")
            
            if [ "$error_count" -eq 0 ] && [ "$warning_count" -eq 0 ]; then
                log_status "OK" "No errors or warnings in recent log"
            elif [ "$error_count" -eq 0 ]; then
                log_status "WARN" "$warning_count warnings in recent log"
            else
                log_status "ERROR" "$error_count errors, $warning_count warnings in recent log"
            fi
        fi
    fi
    
    echo
}

# Scheduling status
show_scheduling_status() {
    echo -e "${BLUE}⏰ SCHEDULING STATUS${NC}"
    echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
    
    # Check cron jobs
    local cron_jobs=0
    if crontab -l 2>/dev/null | grep -q "backup-plex"; then
        cron_jobs=$(crontab -l 2>/dev/null | grep -c "backup-plex")
    fi
    if [ "$cron_jobs" -gt 0 ]; then
        log_status "OK" "Cron jobs configured: $cron_jobs"
        echo -e "${YELLOW}Cron Schedule:${NC}"
        crontab -l 2>/dev/null | grep "backup-plex" | sed 's/^/  /'
    else
        log_status "WARN" "No cron jobs found for backup-plex"
    fi
    
    # Check systemd timers
    if systemctl list-timers --all 2>/dev/null | grep -q "plex-backup"; then
        log_status "OK" "Systemd timer configured"
        local timer_status=$(systemctl is-active plex-backup.timer 2>/dev/null || echo "inactive")
        if [ "$timer_status" = "active" ]; then
            log_status "OK" "Timer is active"
            local next_run=$(systemctl list-timers plex-backup.timer 2>/dev/null | grep "plex-backup" | awk '{print $1, $2}')
            if [ -n "$next_run" ]; then
                log_status "INFO" "Next run: $next_run"
            fi
        else
            log_status "WARN" "Timer is inactive"
        fi
    else
        log_status "INFO" "No systemd timer configured"
    fi
    
    echo
}

# Health recommendations
show_recommendations() {
    echo -e "${BLUE}💡 RECOMMENDATIONS${NC}"
    echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
    
    local recommendations=()
    
    # Check backup age
    if [ -d "$BACKUP_ROOT" ]; then
        local latest_backup=$(find "$BACKUP_ROOT" -maxdepth 1 -type d -name "????????" 2>/dev/null | sort | tail -1)
        if [ -n "$latest_backup" ]; then
            local backup_date=$(basename "$latest_backup")
            local backup_age_days=$(( ($(date +%s) - $(date -d "${backup_date:0:4}-${backup_date:4:2}-${backup_date:6:2}" +%s 2>/dev/null || echo "0")) / 86400 ))
            if [ "$backup_age_days" -gt 7 ]; then
                recommendations+=("Consider running a manual backup - latest backup is $backup_age_days days old")
            fi
        else
            recommendations+=("No backups found - run initial backup with: sudo ./backup-plex.sh")
        fi
    fi
    
    # Check scheduling
    local cron_jobs=0
    if crontab -l 2>/dev/null | grep -q "backup-plex"; then
        cron_jobs=$(crontab -l 2>/dev/null | grep -c "backup-plex")
    fi
    if [ "$cron_jobs" -eq 0 ] && ! systemctl list-timers --all 2>/dev/null | grep -q "plex-backup"; then
        recommendations+=("Set up automated backup scheduling with cron or systemd timer")
    fi
    
    # Check disk space
    if [ -d "$BACKUP_ROOT" ]; then
        local used_percentage=$(df "$BACKUP_ROOT" 2>/dev/null | awk 'NR==2 {print $5}' | sed 's/%//')
        if [ -n "$used_percentage" ] && [ "$used_percentage" -gt 85 ]; then
            recommendations+=("Backup disk usage is high ($used_percentage%) - consider cleaning old backups")
        fi
    fi
    
    # Check dependencies
    if ! command -v jq >/dev/null 2>&1; then
        recommendations+=("Install jq for enhanced performance monitoring: sudo apt install jq")
    fi
    
    # Show recommendations
    if [ ${#recommendations[@]} -eq 0 ]; then
        log_status "OK" "No immediate recommendations - system looks healthy!"
    else
        for rec in "${recommendations[@]}"; do
            log_status "INFO" "$rec"
        done
    fi
    
    echo
}

# Footer with refresh info
show_footer() {
    if [ "$WATCH_MODE" = true ]; then
        echo -e "${CYAN}━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━${NC}"
        echo -e "${CYAN}📡 WATCH MODE: Refreshing every ${REFRESH_INTERVAL} seconds | Press Ctrl+C to exit${NC}"
    else
        echo -e "${CYAN}━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━${NC}"
        echo -e "${CYAN}💡 Use --watch for continuous monitoring | Use --help for options${NC}"
    fi
}

# Main dashboard function
show_dashboard() {
    clear_screen
    show_header
    check_system_status
    check_backup_status
    show_performance_metrics
    show_recent_activity
    show_scheduling_status
    show_recommendations
    show_footer
}

# Main execution
main() {
    if [ "$WATCH_MODE" = true ]; then
        # Validate refresh interval
        if ! [[ "$REFRESH_INTERVAL" =~ ^[0-9]+$ ]] || [ "$REFRESH_INTERVAL" -lt 1 ]; then
            echo "Error: Invalid refresh interval. Must be a positive integer."
            exit 1
        fi
        
        # Continuous monitoring
        while true; do
            show_dashboard
            sleep "$REFRESH_INTERVAL"
        done
    else
        # Single run
        show_dashboard
    fi
}

# Handle interrupts gracefully in watch mode
trap 'echo -e "\n\n${YELLOW}Monitoring stopped by user${NC}"; exit 0' INT TERM

# Run main function
main "$@"