<?php

namespace Tempo\Finance\Payables;

use Illuminate\Database\Schema\Blueprint;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Schema;

/** Shared additive schema; installation never grants access or imports documents. */
final class PayablesSchema
{
    public static function install(): void
    {
        $driver = DB::connection()->getDriverName();
        if (! in_array($driver, ['pgsql', 'sqlite'], true)) {
            throw new \LogicException('Unsupported payables database.');
        }
        $tables = ['pa_sources', 'pa_proposals', 'pa_obligations', 'pa_events', 'pa_outbox', 'pa_commands'];
        $all = [...$tables, 'pa_access'];
        $existing = array_filter($all, fn ($table) => Schema::hasTable($table));
        if ($existing) {
            throw new \LogicException('Payables tables already exist; explicit schema reconciliation required.');
        }
        $scope = function (Blueprint $t) {
            foreach (['tenant_id', 'company_id', 'unit_id'] as $k) {
                $t->unsignedBigInteger($k);
            }
        };
        Schema::create('pa_access', function (Blueprint $t) use ($scope) {
            $t->id();
            $scope($t);
            $t->unsignedBigInteger('user_id');
            $t->string('person');
            $t->string('action');
            $t->unique(['tenant_id', 'company_id', 'unit_id', 'user_id', 'action']);
        });
        Schema::create('pa_sources', function (Blueprint $t) use ($scope) {
            $t->id();
            $scope($t);
            $t->string('source_key', 64)->unique();
            $t->unsignedBigInteger('local_source_id');
            $t->timestamp('created_at');
        });
        Schema::create('pa_proposals', function (Blueprint $t) use ($scope) {
            $t->id();
            $scope($t);
            $t->foreignId('source_id')->constrained('pa_sources');
            $t->string('source_revision', 64);
            $t->integer('capture_version');
            $t->jsonb('snapshot');
            $t->jsonb('missing');
            $t->unsignedBigInteger('prepared_by');
            $t->string('prepared_person');
            $t->text('reason');
            $t->timestamp('created_at');
            $t->unique(['source_id', 'capture_version']);
        });
        Schema::create('pa_obligations', function (Blueprint $t) use ($scope) {
            $t->id();
            $scope($t);
            $t->foreignId('source_id')->unique()->constrained('pa_sources');
            $t->foreignId('proposal_id')->constrained('pa_proposals');
            $t->string('source_revision', 64);
            $t->bigInteger('principal_minor');
            $t->string('currency', 3);
            $t->date('due_on')->nullable();
            $t->unsignedBigInteger('recognised_by');
            $t->string('recognised_person');
            $t->text('reason');
            $t->timestamp('created_at');
        });
        Schema::create('pa_commands', function (Blueprint $t) use ($scope) {
            $t->id();
            $scope($t);
            $t->unsignedBigInteger('actor_id');
            $t->uuid('command_key');
            $t->string('request_hash', 64);
            $t->jsonb('result');
            $t->timestamp('created_at');
            $t->unique(['tenant_id', 'company_id', 'unit_id', 'actor_id', 'command_key']);
        });
        Schema::create('pa_events', function (Blueprint $t) use ($scope) {
            $t->id();
            $scope($t);
            $t->foreignId('source_id')->constrained('pa_sources');
            $t->unsignedBigInteger('actor_id');
            $t->string('kind');
            $t->jsonb('payload');
            $t->timestamp('created_at');
        });
        Schema::create('pa_outbox', function (Blueprint $t) {
            $t->foreignId('event_id')->primary()->constrained('pa_events');
            $t->string('state');
        });
        if ($driver === 'pgsql') {
            DB::unprepared("CREATE FUNCTION pa_append_only() RETURNS trigger LANGUAGE plpgsql AS $$ BEGIN RAISE EXCEPTION 'PA_APPEND_ONLY'; END $$");
            foreach ($tables as $table) {
                DB::unprepared("CREATE TRIGGER pa_history_immutable BEFORE UPDATE OR DELETE ON {$table} FOR EACH ROW EXECUTE FUNCTION pa_append_only()");
            }
        } else {
            foreach ($tables as $table) {
                foreach (['UPDATE', 'DELETE'] as $operation) {
                    $trigger = $table.'_immutable_'.strtolower($operation);
                    DB::unprepared("CREATE TRIGGER {$trigger} BEFORE {$operation} ON {$table} BEGIN SELECT RAISE(ABORT, 'PA_APPEND_ONLY'); END");
                }
            }
        }
    }
}