<?php

declare(strict_types=1);

namespace App\Http\Resources\FormBuilder;

use App\Models\FormBuilder\FormSubmission;
use Illuminate\Http\Request;
use Illuminate\Http\Resources\Json\JsonResource;

/**
 * Public-facing submission response for /api/v1/public/forms/... endpoints
 * (S2c D7). No PII echo — public_submitter_name / email / ip are stored
 * server-side but never reflected back. Admin metadata (review_status,
 * reviewed_by, schema_snapshot) is never exposed.
 *
 * Shape guarantees:
 *   - `identity_match.status` ∈ null | 'pending' | 'matched' | 'none'
 *   - `schema_drift` is true when the draft's form_schema.version has
 *     advanced since draft creation (D5 contract)
 *   - `values` is keyed by field_slug for easy rehydration on the portal
 *
 * @mixin FormSubmission
 */
final class PublicFormSubmissionResource extends JsonResource
{
    /**
     * @return array<string, mixed>
     */
    public function toArray(Request $request): array
    {
        $this->resource->loadMissing(['schema', 'values.field']);

        $values = [];
        foreach ($this->values as $value) {
            $slug = $value->field?->slug;
            if ($slug === null) {
                continue;
            }
            $values[$slug] = [
                'value' => $value->value,
                'value_anonymised' => (bool) $value->value_anonymised,
            ];
        }

        $status = $this->status instanceof \BackedEnum ? $this->status->value : $this->status;

        $schemaDrift = $this->computeSchemaDrift();
        $identityMatch = $this->formatIdentityMatch();
        $duplicateSubmission = $this->formatDuplicateSubmission();

        return [
            'id' => $this->id,
            'form_schema_id' => $this->form_schema_id,
            'status' => $status,
            'auto_save_count' => (int) $this->auto_save_count,
            'submitted_in_locale' => $this->submitted_in_locale,
            'schema_version_at_submit' => $this->schema_version_at_submit,
            'schema_drift' => $schemaDrift,
            'values' => $values,
            'identity_match' => $identityMatch,
            'duplicate_submission' => $duplicateSubmission,
            'opened_at' => optional($this->opened_at)->toIso8601String(),
            'first_interacted_at' => optional($this->first_interacted_at)->toIso8601String(),
            'submitted_at' => optional($this->submitted_at)->toIso8601String(),
            'submission_duration_seconds' => $this->submission_duration_seconds,
            'created_at' => optional($this->created_at)->toIso8601String(),
            'updated_at' => optional($this->updated_at)->toIso8601String(),
        ];
    }

    private function computeSchemaDrift(): bool
    {
        // The draft was opened against version_at_open; at submit time the
        // schema's current version is frozen into version_at_submit. Drift
        // means the organiser edited the schema between the portal loading
        // the form and the user hitting submit.
        //
        // Drafts without a submit stamp keep the comparison live against
        // the current schema.version so an organiser edit during an open
        // draft also surfaces drift on subsequent PUT/GET calls.

        $atOpen = $this->schema_version_at_open;
        if ($atOpen === null) {
            return false;
        }

        $other = $this->schema_version_at_submit;
        if ($other === null) {
            $schema = $this->schema;
            if ($schema === null) {
                return false;
            }
            $other = (int) $schema->version;
        }

        return (int) $atOpen !== (int) $other;
    }

    /**
     * Duplicate-submission signal. The controller sets
     * `duplicate_submission_data` transiently on the submission model
     * after calling FormSubmissionDuplicateDetector::formatForResponse;
     * when null (no priors, missing email, or detector error) the
     * response renders null and the portal skips the hint.
     *
     * Copy source of truth: frontend falls back to Dutch strings but
     * the backend attaches `title` + `body` so the portal can render
     * without maintaining its own plural-agreement logic.
     *
     * @return array<string, mixed>|null
     */
    private function formatDuplicateSubmission(): ?array
    {
        $raw = $this->getAttribute('duplicate_submission_data');
        if (! is_array($raw)) {
            return null;
        }

        $count = (int) ($raw['count'] ?? 0);
        if ($count < 1) {
            return null;
        }

        $firstIso = (string) ($raw['first_submitted_at'] ?? '');
        $formattedDate = $firstIso !== ''
            ? $this->formatDutchLongDate($firstIso)
            : '';

        return [
            'count' => $count,
            'first_submitted_at' => $firstIso,
            'title' => 'Je hebt je eerder al aangemeld',
            'body' => $count === 1
                ? sprintf(
                    'Op %s heb je dit formulier ook al ingevuld. De organisator ziet beide aanmeldingen en neemt zo snel mogelijk contact op.',
                    $formattedDate,
                )
                : sprintf(
                    'Je hebt dit formulier al %d keer eerder ingevuld (voor het eerst op %s). De organisator ziet alle aanmeldingen en neemt zo snel mogelijk contact op.',
                    $count,
                    $formattedDate,
                ),
        ];
    }

    private function formatDutchLongDate(string $iso): string
    {
        try {
            $formatter = new \IntlDateFormatter(
                'nl_NL',
                \IntlDateFormatter::LONG,
                \IntlDateFormatter::NONE,
                'Europe/Amsterdam',
            );
            $ts = strtotime($iso);
            if ($ts === false) {
                return '';
            }
            $out = $formatter->format($ts);

            return is_string($out) ? $out : '';
        } catch (\Throwable) {
            return '';
        }
    }

    /**
     * Identity-match signal per ARCH §31.1. Populated by the
     * TriggerPersonIdentityMatchOnFormSubmit listener on
     * FormSubmissionSubmitted. Read from the dedicated
     * form_submissions.identity_match_status column.
     *
     * @return array<string, string>|null
     */
    private function formatIdentityMatch(): ?array
    {
        $raw = $this->identity_match_status;
        if ($raw === null || $raw === '') {
            return null;
        }
        $status = $raw instanceof \BackedEnum ? $raw->value : (string) $raw;

        return [
            'status' => $status,
            'message' => match ($status) {
                'pending' => 'We controleren of je al bekend bent bij de organisator. Je gegevens worden gekoppeld zodra zij dit bevestigen.',
                'matched' => 'Je account is gekoppeld aan een bekende deelnemer.',
                'none' => 'Geen bestaand account gevonden — je wordt als nieuwe deelnemer geregistreerd.',
                default => '',
            },
        ];
    }
}