<?php
use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\Schema;

return new class extends Migration {
    public function up(): void
    {
        Schema::create('ab_tests', function (Blueprint $table) {
            $table->id();
            $table->string('uid', 32)->unique();
            $table->unsignedInteger('campaign_id');
            $table->string('status', 20)->default('draft'); // draft | running | completed | cancelled
            $table->string('winner_criteria', 20)->default('open_rate'); // open_rate | click_rate | manual
            $table->unsignedBigInteger('winner_variant_id')->nullable();
            $table->unsignedTinyInteger('test_percentage')->default(100); // % of list used for test (remainder gets winner)
            $table->unsignedSmallInteger('winner_wait_hours')->nullable(); // null = manual winner selection
            $table->timestamp('winner_sent_at')->nullable();
            $table->timestamps();

            $table->foreign('campaign_id')->references('id')->on('campaigns')->onDelete('cascade');
        });
    }

    public function down(): void
    {
        Schema::dropIfExists('ab_tests');
    }
};