<?php

namespace App\Jobs\Machine;

use App\Models\Machine\Machine;
use App\Models\Machine\RemoteCommand;
use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Foundation\Bus\Dispatchable;
use Illuminate\Queue\InteractsWithQueue;
use Illuminate\Queue\SerializesModels;
use Illuminate\Support\Facades\Log;

class ProcessCommandAck implements ShouldQueue
{
    use Dispatchable, InteractsWithQueue, Queueable, SerializesModels;

    protected string $serialNo;
    protected array $payload;

    /**
     * 建立 Job 實例
     *
     * @param string $serialNo 機台序號（由 Go Gateway 從 Topic 路徑注入）
     * @param array $payload MQTT Payload，包含 command_id, result, stock
     */
    public function __construct(string $serialNo, array $payload)
    {
        $this->serialNo = $serialNo;
        $this->payload = $payload;
    }

    /**
     * 處理 B055 出貨回報 ACK
     * 原始邏輯移植自 MachineController::reportDispenseResult()
     */
    public function handle(): void
    {
        $commandId = $this->payload['command_id'] ?? null;
        $resultCode = $this->payload['result'] ?? null;
        $stockReported = $this->payload['stock'] ?? null;

        if (empty($commandId)) {
            Log::warning('MQTT CommandAck: Missing command_id', [
                'serial_no' => $this->serialNo,
                'payload' => $this->payload
            ]);
            return;
        }

        $command = RemoteCommand::find($commandId);

        if (!$command) {
            Log::warning('MQTT CommandAck: Command not found', [
                'serial_no' => $this->serialNo,
                'command_id' => $commandId
            ]);
            return;
        }

        $machine = $command->machine;

        // 【優先執行】更新機台為在線狀態 (只要收到訊息就代表在線，不受指令狀態影響)
        if ($machine) {
            $machine->update([
                'last_heartbeat_at' => now(),
                'status' => 'online',
            ]);
        }

        // 核心邏輯：只有處於 pending 狀態的指令才處理後續的業務邏輯 (如庫存異動)
        if ($command->status !== 'pending') {
            Log::info('MQTT CommandAck: Command already processed, ignoring business logic', [
                'command_id' => $commandId,
                'current_status' => $command->status,
            ]);
            return;
        }

        // 判定執行結果 (result: "success" 或 "0" 代表成功)
        $status = in_array($resultCode, ['success', '0'], true) ? 'success' : 'failed';

        $payloadUpdates = [
            'reported_stock' => $stockReported,
            'report_result' => $resultCode,
        ];

        $machine = $command->machine;

        if ($command->command_type === 'dispense') {
            // 若成功，連動更新貨道庫存
            if ($status === 'success' && isset($command->payload['slot_no'])) {
                $slotNo = $command->payload['slot_no'];
                $slot = $machine->slots()->where('slot_no', $slotNo)->first();
                
                if ($slot) {
                    $oldStock = $slot->stock;
                    // 若 APP 回傳的庫存大於 0 則使用回傳值，否則執行扣減
                    $newStock = (int) ($stockReported ?? 0);
                    if ($newStock <= 0 && $oldStock > 0) {
                        $newStock = $oldStock - 1;
                    }

                    $finalStock = max(0, $newStock);
                    $slot->update(['stock' => $finalStock]);

                    // 紀錄庫存變化供前端顯示
                    $payloadUpdates['old_stock'] = $oldStock;
                    $payloadUpdates['new_stock'] = $finalStock;

                    ProcessStateLog::dispatch(
                        $machine->id,
                        $machine->company_id,
                        "Remote dispense successful for slot :slot",
                        'info',
                        ['slot' => $slotNo]
                    );
                }
            }
        } elseif ($command->command_type === 'reload_stock') {
            // 若同步失敗，自動 Rollback 回滾庫存
            if ($status === 'failed' && isset($command->payload['slot_no'], $command->payload['old'])) {
                $slotNo = $command->payload['slot_no'];
                $slot = $machine->slots()->where('slot_no', $slotNo)->first();

                if ($slot) {
                    $oldData = $command->payload['old'];
                    $slot->update([
                        'stock' => $oldData['stock'],
                        'expiry_date' => $oldData['expiry_date'] ?? null,
                        'batch_no' => $oldData['batch_no'] ?? null,
                    ]);

                    Log::warning('MQTT CommandAck failed, rolled back inventory', [
                        'serial_no' => $this->serialNo,
                        'slot_no' => $slotNo,
                        'rolled_back_to' => $oldData
                    ]);
                }
            }
        }

        $command->update([
            'status' => $status,
            'executed_at' => now(),
            'payload' => array_merge($command->payload, $payloadUpdates),
        ]);

        Log::info("MQTT CommandAck processed", [
            'serial_no' => $this->serialNo,
            'command_id' => $commandId,
            'status' => $status,
        ]);
    }
}