<?php

namespace App\Services;

use App\Events\DeviceStateChanged;
use App\Jobs\PollShellyDevice;
use App\Models\Command;
use App\Models\Device;
use App\Models\DeviceState;
use App\Models\Entity;
use App\Support\Drivers\DeviceDriver;
use App\Support\Drivers\ShellyHttpDriver;
use App\Support\Drivers\ShellyMqttDriver;
use Illuminate\Support\Facades\Auth;

/**
 * The one path from UI/automations to a device (H1). Resolves the driver, executes the
 * command and writes an audit row to `commands` — always, success or failure.
 */
class DeviceCommandService
{
    public function toggle(Entity $entity, string $source = 'user'): Command
    {
        $current = (bool) data_get($entity->state?->state, 'on', false);

        return $this->setOn($entity, ! $current, $source);
    }

    public function setOn(Entity $entity, bool $on, string $source = 'user'): Command
    {
        $command = $this->run(
            $entity->device,
            $entity,
            $on ? 'turn_on' : 'turn_off',
            ['on' => $on],
            $source,
            fn (DeviceDriver $driver) => $on ? $driver->turnOn($entity) : $driver->turnOff($entity),
        );

        $this->simulateDemoEcho($command, $entity, ['on' => $on]);

        return $command;
    }

    public function reboot(Device $device, string $source = 'user'): Command
    {
        return $this->run($device, null, 'reboot', [], $source, fn (DeviceDriver $driver) => $driver->reboot($device));
    }

    public function setLight(Entity $entity, array $params, string $source = 'user'): Command
    {
        $command = $this->run($entity->device, $entity, 'set_light', $params, $source, fn (DeviceDriver $driver) => $driver->setLight($entity, $params));

        $this->simulateDemoEcho($command, $entity, $params);

        return $command;
    }

    /**
     * Demo devices have no real hardware to echo their new state back over MQTT, so the UI would
     * look dead when you toggle them. For a demo device we synthesize that echo — write the new
     * state and broadcast DeviceStateChanged — so the mock home is fully interactive (handoff
     * §13.2, "mock first"). Real devices never take this path; their actual status message does.
     */
    private function simulateDemoEcho(Command $command, Entity $entity, array $state): void
    {
        if ($command->result !== 'ok' || ! $entity->device->demo) {
            return;
        }

        $merged = array_merge($entity->state?->state ?? [], $state);

        DeviceState::updateOrCreate(
            ['entity_id' => $entity->id],
            ['state' => $merged, 'observed_at' => (int) round(microtime(true) * 1_000_000)],
        );

        DeviceStateChanged::dispatch($entity->device->uuid, $entity->key, $merged);
    }

    private function run(Device $device, ?Entity $entity, string $command, array $payload, string $source, callable $action): Command
    {
        $result = 'ok';

        try {
            $action($this->driverFor($device));

            // Local (HTTP) devices don't push state — re-poll so the change reflects promptly.
            if ($result === 'ok' && $device->protocol === 'http') {
                PollShellyDevice::dispatch($device->id);
            }
        } catch (\Throwable $e) {
            report($e);
            $result = 'error: '.$e->getMessage();
        }

        return Command::create([
            'device_id' => $device->id,
            'entity_id' => $entity?->id,
            'source' => $source,
            'user_id' => Auth::id(),
            'command' => $command,
            'payload' => $payload,
            'result' => $result,
        ]);
    }

    private function driverFor(Device $device): DeviceDriver
    {
        return match (true) {
            $device->vendor === 'Shelly' && $device->protocol === 'http' => app(ShellyHttpDriver::class),
            $device->vendor === 'Shelly' && $device->protocol === 'mqtt' => app(ShellyMqttDriver::class),
            default => throw new \RuntimeException("No driver for {$device->vendor}/{$device->protocol}."),
        };
    }
}