<?php

namespace App\Services;

use App\Models\User;
use Brick\Math\BigDecimal;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Validator;
use Illuminate\Validation\Rule;

/** Factual preparation only. Actual contractual exemplars have not been supplied. */
final class CompanyPreparation
{
    public const EVENT = 'company_preparation_saved';

    public const VERSION = 'company-preparation-1';

    public function __construct(private readonly VirtualDesk $desk) {}

    /** @return array<string,mixed> */
    public function definition(): array
    {
        return ['version' => self::VERSION, 'forms' => config('company-comparison.forms'),
            'roles' => ['subscriber' => 'Titular, sócio ou accionista', 'administrator' => 'Administrador ou gerente', 'representative' => 'Representante', 'beneficial_owner' => 'Beneficiário efectivo declarado'],
            'source' => config('company-comparison.source'),
            'template_status' => 'source_pending', 'template_notice' => 'Os sete exemplares referidos no complemento ainda não foram fornecidos. Esta ficha prepara dados para revisão; não é uma minuta contratual, assinatura, registo ou licença.'];
    }

    /** Reuse only the already-authorized, frozen dossier values, never a fresh master lookup.
     * @return array<string,array<string,mixed>> */
    private function sources(\stdClass $case): array
    {
        $payload = $this->desk->decode($case->payload);
        $sources = [];
        if (! empty($payload['name'])) {
            $sources['case_proponent'] = ['name' => $payload['name'], 'kind' => 'person', 'reference' => $case->id,
                'version' => $payload['reuse_consent']['date'] ?? 'creation', 'origin' => 'Proponente conservado na criação do dossier'];
        }
        if ($case->company_id && ! empty($payload['company']['name'])) {
            $sources['case_company'] = ['name' => $payload['company']['name'], 'kind' => 'entity', 'reference' => $case->company_id,
                'version' => $payload['company_version'] ?? null, 'origin' => 'Declaração de empresa conservada no dossier'];
        }

        return $sources;
    }

    /** @param array<string,mixed> $input
     * @param array<string,mixed>|null $definition
     * @return array<string,mixed> */
    public function facts(array $input, ?array $definition = null): array
    {
        $definition ??= $this->definition();
        $text = ['nullable', 'string', 'max:2000'];
        $number = ['nullable', 'string', 'regex:/^\d{1,18}(?:[.,]\d{1,6})?$/D'];
        $rules = ['facts' => ['present', 'array:form,proposed_name,seat,activities,regulated,currency,capital,nominal_value,management,binding,notes,parties'],
            'facts.form' => ['nullable', Rule::in(array_keys($definition['forms']))],
            'facts.proposed_name' => ['nullable', 'string', 'max:250'], 'facts.seat' => $text, 'facts.activities' => $text,
            'facts.regulated' => ['nullable', Rule::in(['unknown', 'yes', 'no'])],
            'facts.currency' => ['nullable', 'string', 'regex:/^[A-Z]{3}$/D'], 'facts.capital' => $number, 'facts.nominal_value' => $number,
            'facts.management' => $text, 'facts.binding' => $text, 'facts.notes' => $text,
            'facts.parties' => ['sometimes', 'array', 'list', 'max:100'],
            'facts.parties.*' => ['array:id,name,kind,source,roles,represented_id,cash,in_kind,paid,share_count,work,commitment'],
            'facts.parties.*.id' => ['required', 'uuid', 'distinct'], 'facts.parties.*.name' => ['nullable', 'string', 'max:250'],
            'facts.parties.*.kind' => ['required', Rule::in(['person', 'entity'])],
            'facts.parties.*.source' => ['nullable', Rule::in(['case_proponent', 'case_company'])],
            'facts.parties.*.roles' => ['present', 'array', 'list', 'max:4'],
            'facts.parties.*.roles.*' => ['string', Rule::in(array_keys($definition['roles']))],
            'facts.parties.*.represented_id' => ['nullable', 'uuid'],
            'facts.parties.*.cash' => $number, 'facts.parties.*.in_kind' => $number, 'facts.parties.*.paid' => $number,
            'facts.parties.*.share_count' => ['nullable', 'string', 'regex:/^\d{1,18}$/D'],
            'facts.parties.*.work' => $text, 'facts.parties.*.commitment' => $text];
        $v = Validator::make($input, $rules)->validate()['facts'];
        $facts = [];
        foreach (['form', 'proposed_name', 'seat', 'activities', 'currency', 'management', 'binding', 'notes'] as $key) {
            $facts[$key] = $v[$key] ?? null;
        }
        $facts['regulated'] = $v['regulated'] ?? 'unknown';
        foreach (['capital', 'nominal_value'] as $key) {
            $facts[$key] = $this->decimal($v[$key] ?? null);
        }
        $facts['parties'] = [];
        foreach ($v['parties'] ?? [] as $party) {
            $p = [];
            foreach (['id', 'name', 'kind', 'source', 'represented_id', 'work', 'commitment'] as $key) {
                $p[$key] = $party[$key] ?? null;
            }
            $p['roles'] = array_values(array_unique($party['roles']));
            sort($p['roles']);
            foreach (['cash', 'in_kind', 'paid', 'share_count'] as $key) {
                $p[$key] = $this->decimal($party[$key] ?? null);
            }
            $facts['parties'][] = $p;
        }

        return $facts;
    }

    private function decimal(?string $value): ?string
    {
        return $value === null ? null : (string) BigDecimal::of(str_replace(',', '.', $value))->strippedOfTrailingZeros();
    }

    /** @param array<string,mixed> $facts
     * @param array<string,array<string,mixed>> $sources
     * @param array<string,mixed>|null $previous
     * @return array<string,mixed> */
    private function resolve(array $facts, array $sources, ?array $previous): array
    {
        foreach ($facts['parties'] as &$party) {
            if ($party['source'] !== null) {
                $old = null;
                foreach ($previous['facts']['parties'] ?? [] as $candidate) {
                    if ($candidate['id'] === $party['id'] && $candidate['source'] === $party['source']) {
                        $old = $candidate;
                        break;
                    }
                }
                $source = $old['source_snapshot'] ?? $sources[$party['source']] ?? null;
                abort_unless($source !== null, 422, 'A origem seleccionada não existe neste dossier.');
                $party['name'] = $source['name'];
                $party['kind'] = $source['kind'];
                $party['source_snapshot'] = $source;
            }
        }

        return $facts;
    }

    /** @param array<string,mixed> $facts
     * @return array<string,mixed> */
    public function review(array $facts): array
    {
        $issues = [];
        foreach (['form' => 'Definir a forma a preparar.', 'proposed_name' => 'Indicar a denominação proposta.', 'seat' => 'Indicar a sede proposta.', 'activities' => 'Descrever as actividades.', 'management' => 'Descrever a administração pretendida.', 'binding' => 'Indicar a forma de obrigar pretendida.'] as $key => $message) {
            if (! $facts[$key]) {
                $issues[] = $message;
            }
        }
        $subscribers = array_values(array_filter($facts['parties'], fn ($p) => in_array('subscriber', $p['roles'], true)));
        if ($subscribers === []) {
            $issues[] = 'Identificar os titulares, sócios ou accionistas.';
        }
        if ($facts['form'] === 'collective' && count($subscribers) < 2) {
            $issues[] = 'A forma colectiva exige pelo menos dois sócios (artigo 264).';
        }
        if ($facts['form'] === 'individual' && count($subscribers) > 1) {
            $issues[] = 'A titularidade individual não corresponde a vários titulares.';
        }
        $corporate = $facts['form'] !== null && $facts['form'] !== 'individual';
        $shares = in_array($facts['form'], ['anonymous', 'simplified'], true);
        $total = BigDecimal::zero();
        $paid = BigDecimal::zero();
        $units = BigDecimal::zero();
        $complete = $subscribers !== [];
        $paymentsComplete = $complete;
        $unitsComplete = $complete;
        $ids = array_column($facts['parties'], 'id');
        $usedSources = [];
        foreach ($facts['parties'] as $party) {
            if ($party['source'] && in_array($party['source'], $usedSources, true)) {
                $issues[] = 'A mesma origem foi seleccionada em mais de uma linha; conferir duplicação sem fundir pessoas por nome.';
            }
            $usedSources[] = $party['source'];
            if (! $party['name'] || $party['roles'] === []) {
                $issues[] = 'Completar o nome e os papéis de cada interveniente.';
            }
            if (in_array('representative', $party['roles'], true) && (! $party['represented_id'] || $party['represented_id'] === $party['id'] || ! in_array($party['represented_id'], $ids, true))) {
                $issues[] = 'Identificar quem cada representante representa, numa linha distinta.';
            }
            if (! in_array('subscriber', $party['roles'], true) || ! $corporate) {
                continue;
            }
            $complete = $complete && $party['cash'] !== null && $party['in_kind'] !== null;
            $subscription = BigDecimal::of($party['cash'] ?? '0')->plus($party['in_kind'] ?? '0');
            $total = $total->plus($subscription);
            $paymentsComplete = $paymentsComplete && $party['paid'] !== null;
            $paid = $paid->plus($party['paid'] ?? '0');
            if ($party['paid'] !== null && $party['cash'] !== null && $party['in_kind'] !== null && BigDecimal::of($party['paid'])->compareTo($subscription) > 0) {
                $issues[] = 'Uma realização declarada excede a subscrição desse participante.';
            }
            $unitsComplete = $unitsComplete && $party['share_count'] !== null;
            $units = $units->plus($party['share_count'] ?? '0');
            if ($shares && $party['share_count'] !== null && $facts['nominal_value'] !== null && $party['cash'] !== null && $party['in_kind'] !== null && BigDecimal::of($party['share_count'])->multipliedBy($facts['nominal_value'])->compareTo($subscription) !== 0) {
                $issues[] = 'O valor nominal das acções de um participante difere da sua subscrição.';
            }
            if ($party['work'] && $facts['form'] !== 'collective') {
                $issues[] = 'Conferir a admissibilidade da contribuição em trabalho para a forma escolhida.';
            }
        }
        $totals = null;
        if ($corporate) {
            if (! $facts['currency'] || $facts['capital'] === null || ! $complete) {
                $issues[] = 'Completar moeda, capital e entradas em dinheiro/espécie; valores desconhecidos não são zero.';
            }
            if ($complete && $facts['capital'] !== null && $total->compareTo($facts['capital']) !== 0) {
                $issues[] = 'A soma das subscrições difere do capital declarado.';
            }
            if (! $paymentsComplete) {
                $issues[] = 'Completar a realização declarada de cada subscrição; não equivale a prova de pagamento.';
            }
            if ($shares && ($facts['nominal_value'] === null || ! $unitsComplete)) {
                $issues[] = 'Completar o número de acções e o valor nominal para reconciliar as participações.';
            }
            $totals = ['currency' => $facts['currency'], 'subscribed' => $complete && $facts['currency'] ? (string) $total : null,
                'paid' => $paymentsComplete && $facts['currency'] ? (string) $paid : null,
                'unpaid' => $complete && $paymentsComplete && $facts['currency'] ? (string) $total->minus($paid) : null,
                'shares_nominal' => $shares && $unitsComplete && $facts['nominal_value'] !== null && $facts['currency'] ? (string) $units->multipliedBy($facts['nominal_value']) : null];
        }
        if ($facts['regulated'] !== 'no') {
            $issues[] = 'Conferir os requisitos sectoriais ou profissionais da actividade; o objecto não concede licença.';
        }

        return ['issues' => array_values(array_unique($issues)), 'totals' => $totals, 'status' => 'preparation',
            'note' => $facts['form'] === 'collective' ? 'As contribuições em trabalho são conservadas separadamente e não integram o capital (artigo 266).' : 'Valores declarados para preparação; não comprovam entradas, poderes ou registo.'];
    }

    /** @param array<string,mixed> $input
     * @return array<string,mixed> */
    public function view(User $actor, string $id, array $input): array
    {
        $case = $this->desk->case($actor, $id);
        $payload = $this->desk->decode($case->payload);
        $v = Validator::make($input, ['revision' => 'nullable|uuid', 'history_before' => 'nullable|integer|min:1'])->validate();
        $saved = $payload['company_preparation'] ?? null;
        if (! empty($v['revision'])) {
            $event = DB::table('desk_events')->where('case_id', $id)->where('action', self::EVENT)->where('id', $v['revision'])->first();
            abort_unless($event !== null, 404);
            $saved = $this->desk->decode($event->payload)['snapshot'];
        }
        $facts = $saved['facts'] ?? $this->facts(['facts' => []]);
        $events = DB::table('desk_events')->where('case_id', $id)->where('action', self::EVENT)
            ->when(! empty($v['history_before']), fn ($q) => $q->where('event_order', '<', $v['history_before']))
            ->orderByDesc('event_order')->limit(26)->get(['id', 'payload', 'event_order']);

        return ['case' => ['id' => $id, 'title' => $case->title, 'version' => (int) $case->version],
            'canWrite' => ! $case->closed_at && $this->desk->owns($actor, $case), 'historical' => ! empty($v['revision']),
            'definition' => $saved['definition'] ?? $this->definition(), 'facts' => $facts, 'review' => $saved['review'] ?? $this->review($facts), 'saved' => $saved,
            'sources' => $this->sources($case), 'history' => $events->take(25)->map(function ($e) {
                $s = $this->desk->decode($e->payload)['snapshot'];

                return ['id' => $e->id, 'revision' => $s['revision'], 'at' => $s['at']];
            })->all(), 'historyNext' => $events->count() > 25 ? $events[24]->event_order : null];
    }

    /** @param array<string,mixed> $input
     * @return array<string,mixed> */
    public function save(User $actor, string $id, array $input): array
    {
        $this->desk->case($actor, $id, true);
        $v = Validator::make($input, ['version' => 'required|integer|min:1', 'operation_key' => 'required|uuid'])->validate();

        return DB::transaction(function () use ($actor, $id, $v, $input) {
            $case = $this->desk->case($actor, $id, true, true);
            foreach (DB::table('desk_events')->where('case_id', $id)->where('action', self::EVENT)->orderByDesc('event_order')->cursor() as $event) {
                $data = $this->desk->decode($event->payload);
                if ($data['operation_key'] === $v['operation_key']) {
                    $facts = $this->facts($input, $data['snapshot']['definition']);
                    $hash = hash('sha256', json_encode([(int) $v['version'], $facts], JSON_THROW_ON_ERROR));
                    abort_unless(hash_equals($data['request_hash'], $hash), 409, 'A operação já guardou outros dados.');

                    return ['saved' => true, 'replayed' => true, 'revision' => $data['snapshot']['revision']];
                }
            }
            $facts = $this->facts($input);
            $hash = hash('sha256', json_encode([(int) $v['version'], $facts], JSON_THROW_ON_ERROR));
            abort_if($case->closed_at || (int) $case->version !== (int) $v['version'], 409, 'O dossier mudou ou foi fechado. Os dados continuam no formulário; recupere a versão antes de guardar.');
            $payload = $this->desk->decode($case->payload);
            $previous = $payload['company_preparation'] ?? null;
            $resolved = $this->resolve($facts, $this->sources($case), $previous);
            $definition = $this->definition();
            $review = $this->review($resolved);
            if ($previous && $previous['facts'] === $resolved && $previous['definition'] === $definition && $previous['review'] === $review) {
                return ['saved' => true, 'unchanged' => true, 'revision' => $previous['revision']];
            }
            $snapshot = ['revision' => (int) ($previous['revision'] ?? 0) + 1, 'at' => now()->toIso8601String(), 'actor_id' => $actor->id,
                'facts' => $resolved, 'definition' => $definition, 'review' => $review];
            $payload['company_preparation'] = $snapshot;
            $case->version++;
            DB::table('desk_cases')->where('id', $id)->update(['payload' => $this->desk->encode($payload), 'version' => $case->version, 'updated_at' => now()]);
            $this->desk->event($case, $actor, self::EVENT, ['operation_key' => $v['operation_key'], 'request_hash' => $hash, 'snapshot' => $snapshot]);

            return ['saved' => true, 'replayed' => false, 'revision' => $snapshot['revision']];
        });
    }
}