<?php

namespace App\Support;

use App\Models\Auth\DingTalkIdentity;
use App\Models\Auth\User;
use App\Models\Business\CourierOnboarding;
use App\Services\Auth\FinanceRoster;
use App\Utilities\SidebarPermissions;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Str;
use Illuminate\Validation\ValidationException;

class CourierOnboardingReviewers
{
    public const KEY = 'workflow.courier_onboarding_reviewers';
    public const AUDIT_PREFIX = 'workflow.courier_onboarding_reviewer_audit.';

    public function __construct(private readonly FinanceRoster $roster)
    {
    }

    public function settings(): array
    {
        // Read current company settings directly: permission changes must not use model/settings caches.
        $value = DB::table('settings')->where('company_id', company_id())->where('key', self::KEY)->value('value');

        return (json_decode($value ?? '', true) ?: []) + ['first' => [], 'final' => []];
    }

    public function history(): array
    {
        return DB::table('settings')->where('company_id', company_id())
            ->where('key', 'like', self::AUDIT_PREFIX . '%')->orderByDesc('key')->limit(10)->pluck('value')
            ->map(fn ($value) => json_decode($value, true))->all();
    }

    public function save(array $data, User $actor): void
    {
        $resolved = [];
        $next = ['first' => [], 'final' => []];
        foreach (array_keys($next) as $stage) {
            foreach ($data[$stage] as $dingId) {
                if (! isset($resolved[$dingId])) {
                    $account = $this->account($dingId);
                    if (! $account) {
                        throw ValidationException::withMessages([$stage => '所选人员须有本公司启用的钉钉绑定账号，并拥有快递入驻页面权限。']);
                    }
                    $roster = $this->eligible($dingId);
                    if (! $roster) {
                        throw ValidationException::withMessages([$stage => '所选人员已离职、停用或不在当前财务准入范围，请重新选择。']);
                    }
                    $resolved[$dingId] = ['dingtalk_user_id' => $dingId, 'display_name' => $roster['display_name']];
                }
                $next[$stage][] = $resolved[$dingId];
            }
        }
        // At least two distinct identities must be able to complete the workflow.
        if (count($resolved) < 2) {
            throw ValidationException::withMessages(['final' => '初审和复审不能仅配置同一人，请至少选择两名不同人员。']);
        }

        DB::transaction(function () use ($next, $actor): void {
            DB::table('companies')->where('id', company_id())->lockForUpdate()->first();
            $previous = $this->settings();
            $next['updated_at'] = now()->toIso8601String();
            $next['updated_by'] = $actor->name;
            DB::table('settings')->updateOrInsert(['company_id' => company_id(), 'key' => self::KEY], [
                'value' => json_encode($next, JSON_UNESCAPED_UNICODE),
            ]);
            DB::table('settings')->insert([
                'company_id' => company_id(), 'key' => self::AUDIT_PREFIX . Str::ulid(),
                'value' => json_encode(['at' => $next['updated_at'], 'actor_id' => $actor->id,
                    'actor' => $actor->name, 'before' => $previous, 'after' => $next], JSON_UNESCAPED_UNICODE),
            ]);
        });
    }

    public function search(string $term): array
    {
        return array_map(function (array $row): array {
            $dingId = (string) $row['flowerNameId'];
            $account = $this->account($dingId);
            $eligible = $account ? $this->eligible($dingId) : null;

            return [
                'id' => $dingId,
                'name' => trim((string) ($row['flowerName'] ?: $row['name'])),
                'account' => $account?->name,
                'selectable' => $eligible !== null,
                'reason' => ! $account ? '需先登录绑定钉钉、启用账号并开通快递入驻页面权限'
                    : ($eligible === null ? '不符合当前在职或财务准入条件' : '可选'),
            ];
        }, $this->roster->search($term));
    }

    public function stage(CourierOnboarding $onboarding): string
    {
        return $onboarding->status === CourierOnboarding::STATUS_FIRST_APPROVED ? 'final' : 'first';
    }

    public function assertAllowed(CourierOnboarding $onboarding, int $userId, string $stage): void
    {
        abort_unless((int) $onboarding->company_id === (int) company_id(), 403);
        $settings = $this->settings();
        if ($settings['first'] === [] || $settings['final'] === []) {
            throw ValidationException::withMessages(['approval' => '尚未配置初审和复审人员，请管理员到系统设置 → 流程审核权限设置。']);
        }
        $identity = DingTalkIdentity::query()->where('user_id', $userId)->first();
        abort_unless($identity && in_array($identity->dingtalk_user_id, array_column($settings[$stage], 'dingtalk_user_id'), true)
            && $this->account($identity->dingtalk_user_id)?->id === $userId, 403, '你不是当前环节的指定审核人员。');
        if ($stage === 'final' && (int) $onboarding->first_reviewed_by === $userId && ! $this->allowSameReviewer()) {
            throw ValidationException::withMessages(['approval' => '初审人不能同时做财务复审，请另一名指定复审人员处理。']);
        }
        if (! $this->eligible($identity->dingtalk_user_id)) {
            abort(403, '当前花名册身份已失效，不能审核。');
        }
    }

    public function access(CourierOnboarding $onboarding, int $userId): array
    {
        $stage = $this->stage($onboarding);
        try {
            $this->assertAllowed($onboarding, $userId, $stage);
            return ['allowed' => true, 'message' => ''];
        } catch (ValidationException $e) {
            return ['allowed' => false, 'message' => collect($e->errors())->flatten()->first()];
        } catch (\Symfony\Component\HttpKernel\Exception\HttpException $e) {
            return ['allowed' => false, 'message' => $e->getMessage()];
        }
    }

    private function account(string $dingId): ?User
    {
        $identities = DingTalkIdentity::query()->where('dingtalk_user_id', $dingId)->with('user')->limit(2)->get();
        if ($identities->count() !== 1) {
            return null;
        }
        $user = $identities->first()->user;
        if (! $user || ! $user->enabled || ! $user->companies()->where('companies.id', company_id())->exists()) {
            return null;
        }
        $allowed = SidebarPermissions::allowedKeys($user);
        if ($allowed !== null && ! array_intersect(['courier-payables', 'courier-payables/courier-onboarding'], $allowed)) {
            return null;
        }
        return $user;
    }

    private function eligible(string $dingId): ?array
    {
        try {
            return $this->roster->findEligible($dingId);
        } catch (\Throwable $e) {
            // Do not expose connection details or use a stale HR grant.
            throw ValidationException::withMessages(['approval' => '钉钉花名册暂时无法核验，请稍后重试。']);
        }
    }

    private function allowSameReviewer(): bool
    {
        return app()->environment('local', 'testing') && config('courier_onboarding.allow_same_reviewer');
    }
}