<?php

namespace App\Http\Controllers\Api\V1;

use App\Http\Controllers\Controller;
use Illuminate\Database\Query\Builder;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;
use Illuminate\Validation\ValidationException;

class ReferenceCatalogController extends Controller
{
    private const CATALOGS = ['authorities', 'jurisdictions', 'economic-activities'];

    public function index(Request $request, string $catalog): JsonResponse
    {
        $catalog = $this->validatedCatalog($catalog);

        $rules = [
            'q' => ['nullable', 'string', 'max:100'],
            'version' => ['nullable', 'integer', 'min:1'],
            'page' => ['nullable', 'integer', 'min:1'],
            'per_page' => ['nullable', 'integer', 'min:1', 'max:100'],
            'parent_id' => ['nullable', 'uuid'],
            'jurisdiction_id' => ['nullable', 'uuid'],
        ];
        if ($catalog === 'jurisdictions') {
            $rules['type'] = ['required', 'in:country,province,district,admin_post,locality'];
            $rules['parent_id'][] = 'prohibited_if:type,country';
            $rules['parent_id'][] = 'required_if:type,district,admin_post,locality';
        }
        if ($catalog === 'economic-activities') {
            $rules['sector_id'] = ['nullable', 'integer', 'exists:sectors,id'];
        }
        $data = $request->validate($rules);

        $versionQuery = DB::table('reference_catalog_versions')->where('catalog_code', $catalog)->where('locale', 'pt-MZ');
        if (isset($data['version'])) {
            $versionQuery->where('version_no', $data['version'])->whereIn('status', ['published', 'retired']);
        } else {
            $versionQuery->where('status', 'published')
                ->where(fn (Builder $query) => $query->whereNull('valid_from')->orWhere('valid_from', '<=', today()->toDateString()))
                ->where(fn (Builder $query) => $query->whereNull('valid_to')->orWhere('valid_to', '>', today()->toDateString()));
        }
        $version = $versionQuery->orderByDesc('version_no')->first();

        if (isset($data['version']) && ! $version) {
            abort(404, 'Versão publicada do catálogo não encontrada.');
        }

        if (! $version) {
            return response()->json([
                'data' => [],
                'links' => ['next' => null, 'previous' => null],
                'next_page_url' => null,
                'prev_page_url' => null,
                'current_page' => 1,
                'per_page' => $data['per_page'] ?? 20,
                'total' => 0,
                'last_page' => 1,
                'meta' => ['catalog' => $catalog, 'version' => null, 'locale' => 'pt-MZ', 'status' => 'not_published',
                    'current_page' => 1, 'per_page' => $data['per_page'] ?? 20, 'total' => 0, 'last_page' => 1],
            ])->header('Cache-Control', 'public, max-age=60');
        }

        $query = match ($catalog) {
            'authorities' => $this->authorities((string) $version->id, $data),
            'jurisdictions' => $this->jurisdictions($data),
            'economic-activities' => $this->economicActivities((string) $version->id, $data),
        };

        $page = $query->orderBy('code')->orderBy('id')->paginate($data['per_page'] ?? 20)->withQueryString();
        $items = collect($page->items())->map(fn (object $row): array => $this->present($catalog, (array) $row))->values();

        return response()->json([
            'data' => $items,
            'links' => ['next' => $page->nextPageUrl(), 'previous' => $page->previousPageUrl()],
            'next_page_url' => $page->nextPageUrl(),
            'prev_page_url' => $page->previousPageUrl(),
            'current_page' => $page->currentPage(),
            'per_page' => $page->perPage(),
            'total' => $page->total(),
            'last_page' => $page->lastPage(),
            'meta' => ['catalog' => $catalog, 'version' => (int) $version->version_no, 'locale' => $version->locale,
                'source_version' => $version->source_version, 'valid_from' => $version->valid_from, 'valid_to' => $version->valid_to,
                'current_page' => $page->currentPage(), 'per_page' => $page->perPage(), 'total' => $page->total(), 'last_page' => $page->lastPage()],
        ])->header('Cache-Control', 'public, max-age=300')
            ->header('ETag', 'W/"catalog-'.substr(hash('sha256', $catalog.'|'.$version->version_no.'|'.json_encode($data, JSON_THROW_ON_ERROR)), 0, 32).'"');
    }

    /** @param array<string,mixed> $data */
    private function authorities(string $versionId, array $data): Builder
    {
        $query = DB::table('authorities as a')->join('organizations as o', 'o.id', '=', 'a.organization_id')
            ->leftJoin('geo_locations as g', 'g.id', '=', 'a.jurisdiction_id')
            ->where('a.catalog_version_id', $versionId)->where('a.status', 'published')
            ->where('o.data_classification', 'public')->whereNull('o.deleted_at')
            ->where('a.valid_from', '<=', today()->toDateString())
            ->where(fn (Builder $builder) => $builder->whereNull('a.valid_to')->orWhere('a.valid_to', '>', today()->toDateString()))
            ->select(['a.id', 'a.code', 'a.authority_type', 'a.label_pt_mz as name', 'a.organization_id', 'a.jurisdiction_id',
                'g.name as jurisdiction_name', 'a.version_no']);
        if (! empty($data['jurisdiction_id'])) {
            $query->where('a.jurisdiction_id', $data['jurisdiction_id']);
        }
        if (! empty($data['q'])) {
            $this->search($query, $data['q'], ['a.code', 'a.label_pt_mz', 'o.name']);
        }

        return $query;
    }

    /** @param array<string,mixed> $data */
    private function jurisdictions(array $data): Builder
    {
        $query = DB::table('geo_locations')->where('source_system', 'cartografia-workbook')
            ->where('data_classification', 'public')->whereNull('deleted_at')->where('location_type', $data['type'])
            ->select(['id', 'code', 'name', 'parent_id', 'location_type', 'source_code', 'version_no']);
        $parentType = ['province' => 'country', 'district' => 'province', 'admin_post' => 'district', 'locality' => 'admin_post'][$data['type']] ?? null;
        if ($data['type'] !== 'country' && ! empty($data['parent_id'])) {
            $validParent = DB::table('geo_locations')->where('id', $data['parent_id'])->where('location_type', $parentType)
                ->where('source_system', 'cartografia-workbook')->where('data_classification', 'public')->whereNull('deleted_at')->exists();
            if (! $validParent) {
                throw ValidationException::withMessages(['parent_id' => 'Seleccione um território pai activo do nível anterior.']);
            }
            $query->where('parent_id', $data['parent_id']);
        } elseif (in_array($data['type'], ['district', 'admin_post', 'locality'], true)) {
            throw ValidationException::withMessages(['parent_id' => 'Seleccione primeiro o território pai.']);
        }
        if (! empty($data['q'])) {
            $this->search($query, $data['q'], ['code', 'name', 'source_code']);
        }

        return $query;
    }

    /** @param array<string,mixed> $data */
    private function economicActivities(string $versionId, array $data): Builder
    {
        $query = DB::table('economic_activities')->where('catalog_version_id', $versionId)->where('status', 'published')
            ->where('valid_from', '<=', today()->toDateString())
            ->where(fn (Builder $builder) => $builder->whereNull('valid_to')->orWhere('valid_to', '>', today()->toDateString()))
            ->select(['id', 'code', 'label_pt_mz as name', 'parent_id', 'sector_id', 'version_no']);
        if (array_key_exists('parent_id', $data) && $data['parent_id'] !== null) {
            $query->where('parent_id', $data['parent_id']);
        } else {
            $query->whereNull('parent_id');
        }
        if (! empty($data['sector_id'])) {
            $query->where('sector_id', $data['sector_id']);
        }
        if (! empty($data['q'])) {
            $this->search($query, $data['q'], ['code', 'label_pt_mz']);
        }

        return $query;
    }

    /** @param list<literal-string> $columns */
    private function search(Builder $query, string $search, array $columns): void
    {
        $term = '%'.addcslashes($search, '%_\\').'%';
        $query->where(function (Builder $nested) use ($columns, $term): void {
            foreach ($columns as $index => $column) {
                if ($index === 0) {
                    $nested->whereRaw($column.' ILIKE ?', [$term]);
                } else {
                    $nested->orWhereRaw($column.' ILIKE ?', [$term]);
                }
            }
        });
    }

    /** @return 'authorities'|'jurisdictions'|'economic-activities' */
    private function validatedCatalog(string $catalog): string
    {
        abort_unless(in_array($catalog, self::CATALOGS, true), 404);

        return $catalog;
    }

    /**
     * @param  'authorities'|'jurisdictions'|'economic-activities'  $catalog
     * @param  array<string, mixed>  $row
     * @return array<string,mixed>
     */
    private function present(string $catalog, array $row): array
    {
        return match ($catalog) {
            'jurisdictions' => ['id' => $row['id'], 'value' => $row['id'], 'code' => $row['code'], 'name' => $row['name'],
                'label' => $row['name'], 'locale' => 'pt-MZ', 'parent_id' => $row['parent_id'], 'type' => $row['location_type'],
                'source_code' => $row['source_code'], 'version_no' => $row['version_no']],
            'economic-activities' => ['id' => $row['id'], 'value' => $row['code'], 'code' => $row['code'], 'name' => $row['name'],
                'label' => $row['name'], 'locale' => 'pt-MZ', 'parent_id' => $row['parent_id'], 'sector_id' => $row['sector_id'],
                'version_no' => $row['version_no']],
            'authorities' => ['id' => $row['id'], 'value' => $row['code'], 'code' => $row['code'], 'name' => $row['name'],
                'label' => $row['name'], 'locale' => 'pt-MZ', 'authority_type' => $row['authority_type'],
                'organization_id' => $row['organization_id'], 'jurisdiction_id' => $row['jurisdiction_id'],
                'jurisdiction_name' => $row['jurisdiction_name'], 'version_no' => $row['version_no']],
        };
    }
}