from django.core.management.base import BaseCommand
from core.models import AppUser, Library, Channel, MediaItem, Airing, ScheduleTemplate
from core.services.scheduler import ScheduleGenerator
from django.utils import timezone
from datetime import timedelta, date
import textwrap

class Command(BaseCommand):
    help = "Displays a beautifully formatted terminal dashboard of the current backend state."

    def add_arguments(self, parser):
        parser.add_argument('--channel', type=int, help='Inspect specific channel schedule')
        parser.add_argument('--test-generate', action='store_true', help='Trigger generation for today if inspecting a channel')

    def get_color(self, text, code):
        """Helper to wrap string in bash color codes"""
        return f"\033[{code}m{text}\033[0m"

    def handle(self, *args, **options):
        channel_id = options.get('channel')
        test_generate = options.get('test_generate')

        if channel_id:
            self.inspect_channel(channel_id, test_generate)
            return

        # 1. Gather Aggregate Metrics
        total_users = AppUser.objects.count()
        total_libraries = Library.objects.count()
        total_channels = Channel.objects.count()
        total_media = MediaItem.objects.count()
        total_templates = ScheduleTemplate.objects.count()

        # Gather near-term Airing metrics
        now = timezone.now()
        tomorrow = now + timedelta(days=1)
        airings_today = Airing.objects.filter(starts_at__gte=now, starts_at__lt=tomorrow).count()
        airings_total = Airing.objects.count()
        
        self.stdout.write(self.get_color("\n=== PYTV Backend State Dashboard ===", "1;34"))
        self.stdout.write(f"\n{self.get_color('Core Metrics:', '1;36')}")
        self.stdout.write(f"  Users:        {self.get_color(str(total_users), '1;32')}")
        self.stdout.write(f"  Libraries:    {self.get_color(str(total_libraries), '1;32')}")
        self.stdout.write(f"  Media Items:  {self.get_color(str(total_media), '1;32')}")
        self.stdout.write(f"  Channels:     {self.get_color(str(total_channels), '1;32')}")
        
        self.stdout.write(f"\n{self.get_color('Scheduling Engine:', '1;36')}")
        self.stdout.write(f"  Active Templates:     {self.get_color(str(total_templates), '1;33')}")
        self.stdout.write(f"  Airings (Next 24h):   {self.get_color(str(airings_today), '1;33')}")
        self.stdout.write(f"  Airings (Total):      {self.get_color(str(airings_total), '1;33')}")
        
        # 2. Build Tree View of Channels
        self.stdout.write(f"\n{self.get_color('Channel Tree:', '1;36')}")
        
        channels = Channel.objects.prefetch_related('scheduletemplate_set').all()
        if not channels:
            self.stdout.write("  (No channels configured)")
        
        for c in channels:
            status_color = "1;32" if c.is_active else "1;31"
            status_text = "ACTIVE" if c.is_active else "INACTIVE"
            self.stdout.write(f"\n  📺 [{c.id}] {c.name} (Ch {c.channel_number or '-'}) ({self.get_color(status_text, status_color)})")
            
            # Show templates
            templates = c.scheduletemplate_set.filter(is_active=True).order_by('-priority')
            if not templates:
                self.stdout.write("      ⚠️  No active schedule templates.")
            else:
                for t in templates:
                    blocks_count = t.scheduleblock_set.count()
                    self.stdout.write(f"      📄 Template: {t.name} (Priority {t.priority}) -> {blocks_count} Blocks")
                    
        self.stdout.write(f"\nUse {self.get_color('--channel <id>', '1;37')} to inspect detailed schedule.\n")

    def inspect_channel(self, channel_id, test_generate):
        try:
            channel = Channel.objects.get(id=channel_id)
        except Channel.DoesNotExist:
            self.stdout.write(self.get_color(f"Error: Channel {channel_id} not found.", "1;31"))
            return

        if test_generate:
            self.stdout.write(self.get_color(f"\nTriggering schedule generation for {channel.name}...", "1;33"))
            generator = ScheduleGenerator(channel)
            count = generator.generate_for_date(date.today())
            self.stdout.write(f"Done. Created {self.get_color(str(count), '1;32')} new airings.")

        now = timezone.now()
        end_window = now + timedelta(hours=12)
        
        airings = Airing.objects.filter(
            channel=channel,
            ends_at__gt=now,
            starts_at__lt=end_window
        ).select_related('media_item').order_by('starts_at')

        self.stdout.write(self.get_color(f"\n=== Schedule for {channel.name} (Next 12h) ===", "1;34"))
        
        if not airings:
            self.stdout.write(self.get_color("  (No airings scheduled in this window)", "1;33"))
        else:
            for a in airings:
                time_str = f"{a.starts_at.strftime('%H:%M')} - {a.ends_at.strftime('%H:%M')}"
                if a.starts_at <= now <= a.ends_at:
                    self.stdout.write(f"  {self.get_color('▶ ON AIR', '1;32')} {self.get_color(time_str, '1;37')} | {a.media_item.title}")
                else:
                    self.stdout.write(f"          {time_str} | {a.media_item.title}")

        self.stdout.write("\n")