import esphome.codegen as cg
import esphome.config_validation as cv
from esphome.const import CONF_ID, ESP_PLATFORM_ESP32, CONF_INTERVAL, \
    CONF_DURATION
from esphome.core import coroutine

ESP_PLATFORMS = [ESP_PLATFORM_ESP32]
AUTO_LOAD = ['xiaomi_ble']

CONF_ESP32_BLE_ID = 'esp32_ble_id'
CONF_SCAN_PARAMETERS = 'scan_parameters'
CONF_WINDOW = 'window'
CONF_ACTIVE = 'active'
esp32_ble_tracker_ns = cg.esphome_ns.namespace('esp32_ble_tracker')
ESP32BLETracker = esp32_ble_tracker_ns.class_('ESP32BLETracker', cg.Component)
ESPBTDeviceListener = esp32_ble_tracker_ns.class_('ESPBTDeviceListener')


def validate_scan_parameters(config):
    duration = config[CONF_DURATION]
    interval = config[CONF_INTERVAL]
    window = config[CONF_WINDOW]

    if window > interval:
        raise cv.Invalid("Scan window ({}) needs to be smaller than scan interval ({})"
                         "".format(window, interval))

    if interval.total_milliseconds * 3 > duration.total_milliseconds:
        raise cv.Invalid("Scan duration needs to be at least three times the scan interval to"
                         "cover all BLE channels.")

    return config


CONFIG_SCHEMA = cv.Schema({
    cv.GenerateID(): cv.declare_id(ESP32BLETracker),
    cv.Optional(CONF_SCAN_PARAMETERS, default={}): cv.All(cv.Schema({
        cv.Optional(CONF_DURATION, default='5min'): cv.positive_time_period_seconds,
        cv.Optional(CONF_INTERVAL, default='320ms'): cv.positive_time_period_milliseconds,
        cv.Optional(CONF_WINDOW, default='200ms'): cv.positive_time_period_milliseconds,
        cv.Optional(CONF_ACTIVE, default=True): cv.boolean,
    }), validate_scan_parameters),

    cv.Optional('scan_interval'): cv.invalid("This option has been removed in 1.14 (Reason: "
                                             "it never had an effect)"),
}).extend(cv.COMPONENT_SCHEMA)

ESP_BLE_DEVICE_SCHEMA = cv.Schema({
    cv.GenerateID(CONF_ESP32_BLE_ID): cv.use_id(ESP32BLETracker),
})


def to_code(config):
    var = cg.new_Pvariable(config[CONF_ID])
    yield cg.register_component(var, config)
    params = config[CONF_SCAN_PARAMETERS]
    cg.add(var.set_scan_duration(params[CONF_DURATION]))
    cg.add(var.set_scan_interval(int(params[CONF_INTERVAL].total_milliseconds / 0.625)))
    cg.add(var.set_scan_window(int(params[CONF_WINDOW].total_milliseconds / 0.625)))
    cg.add(var.set_scan_active(params[CONF_ACTIVE]))


@coroutine
def register_ble_device(var, config):
    paren = yield cg.get_variable(config[CONF_ESP32_BLE_ID])
    cg.add(paren.register_listener(var))
    yield var