<?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('chat_sessions', function (Blueprint $table) {
            $table->uuid('session_id')->primary();
            $table->string('session_name', 255)->nullable();
            $table->string('status', 16)->default('OPEN');
            $table->unsignedBigInteger('last_seq')->default(0);
            $table->timestamps();
        });

        Schema::create('messages', function (Blueprint $table) {
            $table->uuid('message_id')->primary();
            $table->uuid('session_id');
            $table->string('role', 32);
            $table->string('type', 64);
            $table->text('content')->nullable();
            $table->jsonb('payload')->nullable();
            $table->timestamp('created_at')->useCurrent();
            $table->unsignedBigInteger('seq');
            $table->uuid('reply_to')->nullable();
            $table->string('dedupe_key', 128)->nullable();

            $table->foreign('session_id')->references('session_id')->on('chat_sessions')->onDelete('cascade');
            $table->unique(['session_id', 'seq']);
            $table->unique(['session_id', 'dedupe_key']);
            $table->index(['session_id', 'seq']);
        });
    }

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