import os
from pathlib import Path
import dotenv

SITE_NAME = "Nexus v5"
DISPATCH_TEAM_PROFILE_ID = os.getenv('DISPATCH_TEAM_PROFILE_ID')

# --- Security: Oathkeeper Verification ---
OATHKEEPER_SECRET = os.getenv('OATHKEEPER_SECRET')

# --- AI Chat: Anthropic Claude API ---
ANTHROPIC_API_KEY = os.getenv('ANTHROPIC_API_KEY', '')
ANTHROPIC_MODEL = os.getenv('ANTHROPIC_MODEL', 'claude-sonnet-4-20250514')

# --- Initial Setup ---
dotenv.load_dotenv()
BASE_DIR = Path(__file__).resolve().parent.parent
SECRET_KEY = os.getenv('SECRET_KEY')
DEBUG = os.getenv('DEBUG', 'False').lower() in ('true', '1', 't')
ALLOWED_HOSTS = ['*']

# --- Unified Redis/Valkey Configuration ---
REDIS_HOST = os.getenv('REDIS_HOST')
REDIS_PORT = os.getenv('REDIS_PORT')
REDIS_USERNAME = os.getenv('REDIS_USERNAME', '')
REDIS_PASSWORD = os.getenv('REDIS_PASSWORD')
REDIS_CLUSTER_MODE = os.getenv('REDIS_CLUSTER_MODE', 'False').lower() in ('true', '1', 't')
# ACL auth format: username:password@ (username required for Valkey ACL)
REDIS_AUTH = f"{REDIS_USERNAME}:{REDIS_PASSWORD}@" if REDIS_PASSWORD else ""

# Sentinel configuration (for HA failover)
# Format: "host1:port1,host2:port2,host3:port3"
REDIS_SENTINEL_HOSTS = os.getenv('REDIS_SENTINEL_HOSTS', '')
REDIS_SENTINEL_MASTER = os.getenv('REDIS_SENTINEL_MASTER', 'valkey-ha')
REDIS_SENTINEL_PASSWORD = os.getenv('REDIS_SENTINEL_PASSWORD', '')  # Sentinel auth
REDIS_SENTINEL_MODE = bool(REDIS_SENTINEL_HOSTS)

# Parse sentinel hosts into list of tuples [(host, port), ...]
REDIS_SENTINELS = []
if REDIS_SENTINEL_MODE:
    REDIS_SENTINELS = [
        (h.split(':')[0], int(h.split(':')[1]))
        for h in REDIS_SENTINEL_HOSTS.split(',')
    ]

# --- Django Applications & Middleware ---
INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'corsheaders',
    'daphne',
    'django.contrib.staticfiles',
    'django.contrib.postgres',
    'core.apps.CoreConfig',
    'channels',
    'strawberry_django',
    'rest_framework',
    'storages',
]

MIDDLEWARE = [
    'core.middleware.ConditionalCorsMiddleware',
    'django.middleware.security.SecurityMiddleware',
    'whitenoise.middleware.WhiteNoiseMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'core.middleware.OryHeaderAuthenticationMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
]

CORS_ALLOWED_ORIGINS = [
    "http://localhost:5173",
    "https://app.example.com",
]

CORS_ALLOWED_ORIGIN_REGEXES = [
    # Regex to allow any origin on the 192.168.100.x subnet
    r"^https?://192\.168\.100\.\d{1,3}(:\d+)?$",
]

# CORS credentials support for cookie-based auth
CORS_ALLOW_CREDENTIALS = True

# Allow common headers for GraphQL
CORS_ALLOW_HEADERS = [
    'accept',
    'accept-encoding',
    'authorization',
    'content-type',
    'dnt',
    'origin',
    'user-agent',
    'x-csrftoken',
    'x-requested-with',
]

CSRF_TRUSTED_ORIGINS = [
    "https://api.example.com",
    "https://app.example.com",
    "https://local.example.com:5173"
]

# --- Channels & ASGI ---
ASGI_APPLICATION = 'config.asgi.application'
if REDIS_SENTINEL_MODE:
    # Sentinel mode: use master discovery for HA failover
    _sentinel_host_config = {
        "sentinels": REDIS_SENTINELS,
        "master_name": REDIS_SENTINEL_MASTER,
        "password": REDIS_PASSWORD,
        "username": REDIS_USERNAME,
        "db": 0,
    }
    if REDIS_SENTINEL_PASSWORD:
        _sentinel_host_config["sentinel_kwargs"] = {"password": REDIS_SENTINEL_PASSWORD}
    CHANNEL_LAYERS = {
        'default': {
            'BACKEND': 'channels_valkey.core.ValkeyChannelLayer',
            'CONFIG': {
                "hosts": [_sentinel_host_config],
                "prefix": "nexus:channels",
            },
        },
    }
elif REDIS_CLUSTER_MODE:
    # Use sharded pubsub for cluster mode
    CHANNEL_LAYERS = {
        'default': {
            'BACKEND': 'channels_valkey.pubsub.ValkeyPubSubChannelLayer',
            'CONFIG': {
                "hosts": [f"valkey://{REDIS_AUTH}{REDIS_HOST}:{REDIS_PORT}/0"],
                "prefix": "nexus:channels",
            },
        },
    }
else:
    CHANNEL_LAYERS = {
        'default': {
            'BACKEND': 'channels_valkey.core.ValkeyChannelLayer',
            'CONFIG': {
                "hosts": [f"valkey://{REDIS_AUTH}{REDIS_HOST}:{REDIS_PORT}/0"],
                "prefix": "nexus:channels",
            },
        },
    }

# --- Framework Settings ---
STRAWBERRY_DJANGO = {
    'FIELD_DESCRIPTION_FROM_HELP_TEXT': True,
    'TYPE_DESCRIPTION_FROM_MODEL_DOCSTRING': True,
    'MUTATIONS_DEFAULT_HANDLE_ERRORS': True,
}

# ---  Security Settings ---
USE_X_FORWARDED_HOST = True
SECURE_PROXY_SSL_HEADER = ('HTTP_X_FORWARDED_PROTO', 'https')

# --- Core Django Settings ---
ROOT_URLCONF = 'config.urls'
TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'APP_DIRS': True,
        'DIRS': [BASE_DIR / 'templates'],
        'OPTIONS': {
            'context_processors': [
                'django.template.context_processors.request',
                'django.contrib.auth.context_processors.auth',
                'django.contrib.messages.context_processors.messages',
            ],
        },
    },
]

# --- Databases & Caches ---
DATABASES = {
    'default': {
        'ENGINE': 'config.db_backend',  # Custom backend for Vault credential reloading
        'NAME': os.getenv('DB_NAME'),
        'HOST': os.getenv('DB_HOST'),
        'PORT': os.getenv('DB_PORT'),
        'USER': os.environ.get('DB_USER'),  # Fallback for local dev
        'PASSWORD': os.environ.get('DB_PASSWORD'),  # Fallback for local dev
        'CONN_MAX_AGE': 600,  # Keep connections for 10 minutes
        'CONN_HEALTH_CHECKS': True,  # Verify connections before reuse
    },
    'admin': {
        'ENGINE': 'config.db_backend',  # Custom backend for Vault credential reloading
        'NAME': os.getenv('DB_NAME'),
        'HOST': os.getenv('DB_HOST'),
        'PORT': os.getenv('DB_PORT'),
        'USER': os.environ.get('DB_ADMIN_USER'),  # Fallback for local dev
        'PASSWORD': os.environ.get('DB_ADMIN_PASSWORD'),  # Fallback for local dev
        'CONN_MAX_AGE': 600,  # Keep connections for 10 minutes
        'CONN_HEALTH_CHECKS': True,  # Verify connections before reuse
    }
}
if REDIS_SENTINEL_MODE:
    # Sentinel mode: use django-valkey with SentinelClient for HA failover
    _valkey_connection_kwargs = {"password": REDIS_PASSWORD}
    if REDIS_USERNAME:
        _valkey_connection_kwargs["username"] = REDIS_USERNAME
    CACHES = {
        "default": {
            "BACKEND": "django_valkey.cache.ValkeyCache",
            "LOCATION": f"valkey://{REDIS_SENTINEL_MASTER}/0",
            "KEY_PREFIX": "nexus:cache",
            "OPTIONS": {
                "CLIENT_CLASS": "django_valkey.client.SentinelClient",
                "SENTINELS": REDIS_SENTINELS,
                "CONNECTION_POOL_CLASS": "valkey.sentinel.SentinelConnectionPool",
                "CONNECTION_POOL_CLASS_KWARGS": _valkey_connection_kwargs,
                "SENTINEL_KWARGS": {"password": REDIS_SENTINEL_PASSWORD} if REDIS_SENTINEL_PASSWORD else {},
            },
        }
    }
elif REDIS_CLUSTER_MODE:
    CACHES = {
        "default": {
            "BACKEND": "django_valkey.cache.ValkeyCache",
            "LOCATION": f"valkey://{REDIS_AUTH}{REDIS_HOST}:{REDIS_PORT}/0",
            "KEY_PREFIX": "nexus:cache",
            "OPTIONS": {
                "CLIENT_CLASS": "django_valkey.client.DefaultClient",
                "VALKEY_CLIENT_CLASS": "valkey.cluster.ValkeyCluster",
                "VALKEY_CLIENT_KWARGS": {
                    "skip_full_coverage_check": True,
                },
            },
        }
    }
else:
    CACHES = {
        "default": {
            "BACKEND": "django_valkey.cache.ValkeyCache",
            "LOCATION": f"valkey://{REDIS_AUTH}{REDIS_HOST}:{REDIS_PORT}/0",
            "KEY_PREFIX": "nexus:cache",
            "OPTIONS": {
                "CLIENT_CLASS": "django_valkey.client.DefaultClient",
            },
        }
    }

# --- Celery Configuration ---
# All Redis usage on /0 with key prefixes for namespace isolation
if REDIS_SENTINEL_MODE:
    # Sentinel mode: use master discovery for HA failover
    # Format: sentinel://user:pass@host1:port/db;sentinel://user:pass@host2:port/db;...
    # Each sentinel URL must include full credentials (for master connection after discovery)
    if REDIS_USERNAME and REDIS_PASSWORD:
        sentinel_urls = ';'.join([
            f"sentinel://{REDIS_USERNAME}:{REDIS_PASSWORD}@{h}:{p}/0"
            for h, p in REDIS_SENTINELS
        ])
    elif REDIS_PASSWORD:
        sentinel_urls = ';'.join([
            f"sentinel://:{REDIS_PASSWORD}@{h}:{p}/0"
            for h, p in REDIS_SENTINELS
        ])
    else:
        sentinel_urls = ';'.join([
            f"sentinel://{h}:{p}/0"
            for h, p in REDIS_SENTINELS
        ])
    CELERY_BROKER_URL = sentinel_urls
    # Use custom backend class that fixes Celery's missing 'username' param for ACL auth
    CELERY_RESULT_BACKEND = f"config.celery.FixedSentinelBackend+{sentinel_urls}"
    CELERY_BROKER_TRANSPORT_OPTIONS = {
        'master_name': REDIS_SENTINEL_MASTER,
        'global_keyprefix': 'nexus:celery:',
    }
    CELERY_RESULT_BACKEND_TRANSPORT_OPTIONS = {
        'master_name': REDIS_SENTINEL_MASTER,
        'global_keyprefix': 'nexus:celery:',
    }
    # Sentinel authentication (if Sentinel itself requires auth, separate from master)
    if REDIS_SENTINEL_PASSWORD:
        CELERY_BROKER_TRANSPORT_OPTIONS['sentinel_kwargs'] = {'password': REDIS_SENTINEL_PASSWORD}
        CELERY_RESULT_BACKEND_TRANSPORT_OPTIONS['sentinel_kwargs'] = {'password': REDIS_SENTINEL_PASSWORD}
elif REDIS_CLUSTER_MODE:
    # Celery 5.3+ supports cluster mode natively
    CELERY_BROKER_URL = f"redis://{REDIS_AUTH}{REDIS_HOST}:{REDIS_PORT}/0"
    CELERY_RESULT_BACKEND = f"redis://{REDIS_AUTH}{REDIS_HOST}:{REDIS_PORT}/0"
    CELERY_BROKER_TRANSPORT_OPTIONS = {
        'global_keyprefix': 'nexus:celery:',
        'fanout_prefix': True,
        'fanout_patterns': True,
    }
    CELERY_RESULT_BACKEND_TRANSPORT_OPTIONS = {'global_keyprefix': 'nexus:celery:'}
    CELERY_BROKER_USE_SSL = False
    CELERY_REDIS_BACKEND_USE_CLUSTER = True
else:
    CELERY_BROKER_URL = f"redis://{REDIS_AUTH}{REDIS_HOST}:{REDIS_PORT}/0"
    CELERY_RESULT_BACKEND = f"redis://{REDIS_AUTH}{REDIS_HOST}:{REDIS_PORT}/0"
    CELERY_BROKER_TRANSPORT_OPTIONS = {'global_keyprefix': 'nexus:celery:'}
    CELERY_RESULT_BACKEND_TRANSPORT_OPTIONS = {'global_keyprefix': 'nexus:celery:'}
CELERY_ACCEPT_CONTENT = ['json']
CELERY_TASK_SERIALIZER = 'json'
CELERY_RESULT_SERIALIZER = 'json'
CELERY_TIMEZONE = 'America/New_York'
CELERY_TASK_TRACK_STARTED = True
CELERY_TASK_TIME_LIMIT = 30 * 60  # 30 minutes
CELERY_TASK_SOFT_TIME_LIMIT = 25 * 60  # 25 minutes
CELERY_BROKER_CONNECTION_RETRY_ON_STARTUP = True

# Celery Beat Schedule (periodic tasks)
from celery.schedules import crontab

CELERY_BEAT_SCHEDULE = {
    'cleanup-old-events': {
        'task': 'core.tasks.event_cleanup.cleanup_old_events',
        'schedule': crontab(hour=2, minute=0),  # Run daily at 2 AM Eastern
    },
    'monitoring-incomplete-work-reminder': {
        'task': 'core.tasks.monitoring.run_monitoring_command',
        'schedule': crontab(hour=8, minute=0),  # 8 AM Eastern
        'args': ['incomplete_work_reminder'],
    },
    'monitoring-nightly-assignments': {
        'task': 'core.tasks.monitoring.run_monitoring_command',
        'schedule': crontab(hour=18, minute=0),  # 6 PM Eastern
        'args': ['nightly_assignments'],
    },
}

# --- Emailer Microservice Configuration ---
# Emailer is a Rust-based REST API for sending emails via Gmail API
EMAILER_BASE_URL = os.getenv('EMAILER_BASE_URL', 'https://email.example.com')
EMAILER_API_KEY = os.getenv('EMAILER_API_KEY', '')
EMAILER_DEFAULT_SENDER = os.getenv('EMAILER_DEFAULT_SENDER', 'noreply@example.com')

# --- Security & Static Files ---
AUTH_PASSWORD_VALIDATORS = [
    {'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator'},
    {'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator'},
    {'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator'},
    {'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator'},
]
STATIC_URL = '/static/'
STATIC_ROOT = BASE_DIR / 'staticfiles'

# --- Media Files & File Upload ---
MEDIA_URL = '/api/media/'

# S3 Storage Configuration (Garage S3-compatible cluster)
# boto3/django-storages use AWS_* naming convention but connect to Garage
AWS_ACCESS_KEY_ID = os.getenv('AWS_ACCESS_KEY_ID')
AWS_SECRET_ACCESS_KEY = os.getenv('AWS_SECRET_ACCESS_KEY')
AWS_STORAGE_BUCKET_NAME = os.getenv('AWS_STORAGE_BUCKET_NAME', 'nexus-media')
AWS_S3_ENDPOINT_URL = os.getenv('AWS_S3_ENDPOINT_URL', 'http://10.10.10.39:3900')
AWS_S3_REGION_NAME = 'garage'  # Garage ignores this but boto3 requires it
AWS_DEFAULT_ACL = None  # Use bucket default
AWS_QUERYSTRING_AUTH = False  # Nginx handles auth, not pre-signed URLs
AWS_S3_FILE_OVERWRITE = False  # Preserve unique filenames

# Legacy MEDIA_ROOT for local dev fallback (not used in production with S3)
MEDIA_ROOT = BASE_DIR / 'media'

# Django 4.2+ STORAGES configuration (replaces deprecated DEFAULT_FILE_STORAGE)
# Uses custom GarageS3Storage that returns nginx-proxied URLs instead of direct S3 URLs
STORAGES = {
    "default": {
        "BACKEND": "config.storage.GarageS3Storage",
    },
    "staticfiles": {
        "BACKEND": "whitenoise.storage.CompressedManifestStaticFilesStorage",
    },
}

# Increased limits for video uploads (250 MB max)
DATA_UPLOAD_MAX_MEMORY_SIZE = 250 * 1024 * 1024  # 250 MB
FILE_UPLOAD_MAX_MEMORY_SIZE = 250 * 1024 * 1024  # 250 MB

# --- Internationalization ---
LANGUAGE_CODE = 'en-us'
TIME_ZONE = 'UTC'
USE_I18N = True
USE_TZ = True
DEFAULT_AUTO_FIELD = 'django.db.models.BigAutoField'