import os
from dotenv import load_dotenv

basedir = os.path.abspath(os.path.dirname(__file__))
projectdir = os.path.dirname(basedir)

# Look for .env beside app/ first (project root), then inside app/.
load_dotenv(os.path.join(projectdir, '.env'))
load_dotenv(os.path.join(basedir, '.env'))


def _resolve_path(value, default):
    """Absolute value as-is; relative resolved against the project root."""
    if not value:
        return default
    return value if os.path.isabs(value) else os.path.join(projectdir, value)


class Config:
    """Base configuration."""
    
    # Flask
    SECRET_KEY = os.environ.get('SECRET_KEY') or 'dev-secret-key-change-in-production'
    
    # Database
    SQLALCHEMY_DATABASE_URI = os.environ.get('DATABASE_URL') or \
        'sqlite:///' + os.path.join(basedir, 'lego_instructions.db')
    SQLALCHEMY_TRACK_MODIFICATIONS = False
    
    # File Upload
    # Defaults to <app>/static/uploads (E:\LIM\app\static\uploads on the
    # Windows install). Set UPLOAD_FOLDER to override — the Docker image
    # points it at a mounted volume, e.g. /data/uploads.
    # A relative value is resolved against the project root, NOT the working
    # directory, so `UPLOAD_FOLDER=app/static/uploads` in .env means the same
    # thing no matter where you run flask from.
    UPLOAD_FOLDER = _resolve_path(os.environ.get('UPLOAD_FOLDER'),
                                  os.path.join(basedir, 'static', 'uploads'))
    MAX_CONTENT_LENGTH = int(os.environ.get('MAX_CONTENT_LENGTH', 52428800))  # 50MB
    ALLOWED_EXTENSIONS = {'pdf', 'png', 'jpg', 'jpeg', 'gif', 'webp'}
    
    # Brickset API
    BRICKSET_API_KEY = os.environ.get('BRICKSET_API_KEY')
    BRICKSET_USERNAME = os.environ.get('BRICKSET_USERNAME')
    BRICKSET_PASSWORD = os.environ.get('BRICKSET_PASSWORD')
    BRICKSET_API_URL = 'https://brickset.com/api/v3.asmx'
    
    # Backups
    # Defaults to <project root>/backups so archives never land inside the
    # uploads tree (which would make each backup include the previous one).
    # Relative values resolve against the project root, as with UPLOAD_FOLDER.
    BACKUP_FOLDER = _resolve_path(os.environ.get('BACKUP_FOLDER'),
                                  os.path.join(projectdir, 'backups'))
    # Keep only the newest N archives after a backup made from the web UI.
    # Set to 0 to keep everything.
    BACKUP_KEEP = int(os.environ.get('BACKUP_KEEP', 5))
    # Ceiling for archives uploaded through the admin page, in bytes.
    # 0 = no limit. This is separate from MAX_CONTENT_LENGTH: backup uploads
    # stream straight to disk and never go through Flask's form parser.
    BACKUP_MAX_UPLOAD = int(os.environ.get('BACKUP_MAX_UPLOAD', 0))

    # Logging
    # Rotating file handler; the admin log viewer reads these files.
    # Docker points LOG_FOLDER at the mounted volume (/data/logs).
    LOG_FOLDER = _resolve_path(os.environ.get('LOG_FOLDER'),
                               os.path.join(projectdir, 'logs'))
    LOG_LEVEL = os.environ.get('LOG_LEVEL', 'INFO')
    LOG_MAX_BYTES = int(os.environ.get('LOG_MAX_BYTES', 2097152))  # 2MB
    LOG_BACKUP_COUNT = int(os.environ.get('LOG_BACKUP_COUNT', 5))
    # Per-request access logging is noisy; off unless you ask for it.
    LOG_ACCESS = os.environ.get('LOG_ACCESS', '0') == '1'

    # Automatic instruction fetcher
    # Pacing (interval, delays, on/off) lives in site_settings so it can be
    # changed from the admin page. These are the hard limits and the switch
    # for the in-process worker thread.
    #
    # Turn the worker off (0) if you drive the queue from Task Scheduler or
    # cron with `flask instructions run` instead, or if you ever run more
    # than one LIM process against the same database.
    INSTRUCTION_FETCH_WORKER = os.environ.get('INSTRUCTION_FETCH_WORKER', '1') != '0'
    # How often the worker wakes to check whether the interval has elapsed.
    INSTRUCTION_FETCH_TICK_SECONDS = int(
        os.environ.get('INSTRUCTION_FETCH_TICK_SECONDS', 20))
    # Refuse anything larger than this, in megabytes. Some Technic manuals
    # are genuinely enormous, hence the generous default.
    FETCH_MAX_FILE_MB = int(os.environ.get('FETCH_MAX_FILE_MB', 150))
    FETCH_TIMEOUT_SECONDS = int(os.environ.get('FETCH_TIMEOUT_SECONDS', 60))

    # Add missing columns automatically at startup. Turn off if you'd
    # rather manage schema changes with Flask-Migrate yourself.
    AUTO_SCHEMA_UPGRADE = os.environ.get('AUTO_SCHEMA_UPGRADE', '1') != '0'

    # Pagination
    SETS_PER_PAGE = int(os.environ.get('SETS_PER_PAGE', 20))


class DevelopmentConfig(Config):
    """Development configuration."""
    DEBUG = True
    TESTING = False


class ProductionConfig(Config):
    """Production configuration."""
    DEBUG = False
    TESTING = False


class TestingConfig(Config):
    """Testing configuration."""
    TESTING = True
    SQLALCHEMY_DATABASE_URI = 'sqlite:///:memory:'
    WTF_CSRF_ENABLED = False


config = {
    'development': DevelopmentConfig,
    'production': ProductionConfig,
    'testing': TestingConfig,
    'default': DevelopmentConfig
}