<?php

use App\Support\DbCompat;
use Illuminate\Database\Migrations\Migration;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Schema;

return new class extends Migration
{
    public function up(): void
    {
        $isPgsql = DbCompat::isPgsql();

        Schema::create('releves', function (Blueprint $table) use ($isPgsql) {
            $table->id();
            $table->foreignId('source_id')->constrained()->cascadeOnDelete();
            // PostgreSQL : JSONB (binary JSON, indexable par GIN)
            // MySQL      : JSON
            if ($isPgsql) {
                $table->jsonb('data');
            } else {
                $table->json('data');
            }
            $table->foreignId('created_by')->constrained('users')->restrictOnDelete();
            $table->foreignId('updated_by')->constrained('users')->restrictOnDelete();
            $table->timestamps();
        });

        // ── Colonnes générées stockées (syntaxe différente selon le SGBD) ──────
        $nomExpr          = DbCompat::generatedJsonCol('nom');
        $prenomExpr       = DbCompat::generatedJsonCol('prenom');
        $dateEvtExpr      = DbCompat::generatedJsonNestedCol('date_evenement.valeur');

        if ($isPgsql) {
            DB::statement("ALTER TABLE releves ADD COLUMN nom TEXT GENERATED ALWAYS AS ({$nomExpr}) STORED");
            DB::statement("ALTER TABLE releves ADD COLUMN prenom TEXT GENERATED ALWAYS AS ({$prenomExpr}) STORED");
            DB::statement("ALTER TABLE releves ADD COLUMN date_evenement TEXT GENERATED ALWAYS AS ({$dateEvtExpr}) STORED");
        } else {
            DB::statement("ALTER TABLE releves ADD COLUMN nom VARCHAR(255) GENERATED ALWAYS AS ({$nomExpr}) STORED");
            DB::statement("ALTER TABLE releves ADD COLUMN prenom VARCHAR(255) GENERATED ALWAYS AS ({$prenomExpr}) STORED");
            DB::statement("ALTER TABLE releves ADD COLUMN date_evenement VARCHAR(255) GENERATED ALWAYS AS ({$dateEvtExpr}) STORED");
        }

        // ── Index B-tree sur les colonnes générées ───────────────────────────
        DB::statement('CREATE INDEX releves_nom_idx ON releves (nom)');
        DB::statement('CREATE INDEX releves_prenom_idx ON releves (prenom)');
        DB::statement('CREATE INDEX releves_date_evenement_idx ON releves (date_evenement)');

        // ── Index GIN sur le JSON complet (PostgreSQL uniquement) ─────────────
        if ($isPgsql) {
            DB::statement('CREATE INDEX releves_data_gin_idx ON releves USING gin (data)');
        }
    }

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