"""
Device configuration management (owner name, car model, avatar, sync status).
Stores in SQLite with option to sync from server (Phase 25.5a).
"""

import json
import os
from . import app_sql


def get_device_config():
    """Get current device config including sync status."""
    sync_enabled = _get_sync_enabled()
    config = {
        "owner_name": app_sql.get_setting("device_owner_name", ""),
        "car_model": app_sql.get_setting("device_car_model", ""),
        "device_name": app_sql.get_setting("device_device_name", ""),
        "avatar_path": app_sql.get_setting("device_avatar_path", ""),
        "sync_enabled": sync_enabled,
    }
    # Fill in any missing values from config file or defaults
    config = _apply_defaults(config)
    return config


def update_device_config(body, errors):
    """Update device config from request body. Returns errors dict if invalid."""
    if not isinstance(body, dict):
        errors["error"] = "Invalid request body"
        return errors

    # Check if sync is enabled; if so, only allow sync-related updates
    sync_enabled = _get_sync_enabled()
    if sync_enabled:
        # User cannot edit these fields if syncing from server
        if any(k in body for k in ["owner_name", "car_model", "avatar_path"]):
            errors["error"] = "Cannot edit device config while server sync is enabled. Server is source of truth."
        # Allow toggling sync_enabled off
        if "sync_enabled" in body and not body["sync_enabled"]:
            _set_sync_enabled(False)
        return errors

    # Not syncing: allow all edits
    if "owner_name" in body:
        value = str(body["owner_name"]).strip()
        if not value or len(value) > 100:
            errors["owner_name"] = "Owner name must be 1-100 characters."
        else:
            app_sql.set_setting("device_owner_name", value)

    if "car_model" in body:
        value = str(body["car_model"]).strip()
        if not value or len(value) > 100:
            errors["car_model"] = "Car model must be 1-100 characters."
        else:
            app_sql.set_setting("device_car_model", value)

    if "device_name" in body:
        value = str(body["device_name"]).strip()
        if not value or len(value) > 100:
            errors["device_name"] = "Device name must be 1-100 characters."
        else:
            app_sql.set_setting("device_device_name", value)

    if "avatar_path" in body:
        value = str(body["avatar_path"]).strip()
        if not value or len(value) > 255:
            errors["avatar_path"] = "Avatar path must be 1-255 characters."
        else:
            app_sql.set_setting("device_avatar_path", value)

    if "sync_enabled" in body:
        if not isinstance(body["sync_enabled"], bool):
            errors["sync_enabled"] = "Must be true or false."
        elif body["sync_enabled"]:
            from . import app_remote_config

            remote = app_remote_config.get_remote_config()
            if not remote["server_url"] or not remote["device_name"] or not remote["api_key_configured"]:
                errors["sync_enabled"] = "Configure server URL, device name, and API key before enabling server sync."
        else:
            _set_sync_enabled(body["sync_enabled"])

    if "sync_enabled" in body and body["sync_enabled"] and "sync_enabled" not in errors:
        _set_sync_enabled(True)

    return errors


def _apply_defaults(config):
    """Fill in any empty config values from config/device.json or hardcoded defaults."""
    config_file_path = os.path.join(
        os.path.dirname(os.path.dirname(__file__)), "config", "device.json"
    )
    file_config = {}
    try:
        if os.path.exists(config_file_path):
            with open(config_file_path, "r") as f:
                file_config = json.load(f)
    except (IOError, json.JSONDecodeError):
        pass

    # Use file config as source of truth for initial values, fallback to hardcoded
    defaults = {
        "owner_name": "quoije",
        "car_model": "Yaris 2013",
        "device_name": "Yaris OBD",
        "avatar_path": "img/yaris.png",
    }
    for key in defaults:
        if not config[key]:
            config[key] = file_config.get(key, defaults[key])
    return config


def _get_sync_enabled():
    """Check if device config sync from server is enabled."""
    return app_sql.get_setting("device_sync_enabled", "0") == "1"


def _set_sync_enabled(enabled):
    """Set device config sync status."""
    app_sql.set_setting("device_sync_enabled", "1" if enabled else "0")