<?php

namespace App\Http\Controllers\Api;

use App\Http\Controllers\Controller;
use App\Models\Company;
use App\Models\Contact;
use App\Models\ContactPhone;
use App\Models\Deal;
use App\Models\Lead;
use App\Services\ActivityLogger;
use App\Support\AccessControl;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Gate;
use Illuminate\Validation\ValidationException;

class ContactController extends Controller
{
    public function index(Request $request): JsonResponse
    {
        Gate::authorize('viewAny', Contact::class);
        $query = Contact::with('phones', 'lead:id,company,first_name,last_name', 'company:id,name', 'deal:id,title');
        AccessControl::scopeContacts($query, auth()->user());

        if ($request->lead_id) {
            $query->where('lead_id', $request->lead_id);
        }
        if ($request->company_id) {
            $query->where('company_id', $request->company_id);
        }
        if ($request->deal_id) {
            $query->where('deal_id', $request->deal_id);
        }
        if ($request->status) {
            $query->where('status', $request->status);
        }
        if ($request->search) {
            $search = $request->search;
            $query->where(fn ($q) => $q->where('name', 'like', "%{$search}%")->orWhere('email', 'like', "%{$search}%"));
        }

        return response()->json($query->latest()->paginate(min((int) $request->get('per_page', 15), 100)));
    }

    public function storeStandalone(Request $request): JsonResponse
    {
        Gate::authorize('create', Contact::class);
        $validated = $this->validateContact($request);
        $this->authorizeParents($validated, 'update');
        $contact = DB::transaction(fn () => $this->createContact($validated));
        ActivityLogger::log('contact_created', "Contact {$contact->name} created", $contact);

        return response()->json($contact->load('phones.lastCaller', 'company:id,name', 'lead:id,company'), 201);
    }

    public function store(Request $request, Lead $lead): JsonResponse
    {
        $this->authorizeLeadAccess($lead);

        $validated = $this->validateContact($request);
        $validated['lead_id'] = $lead->id;
        $this->authorizeParents($validated, 'update');

        $contact = DB::transaction(function () use ($lead, $validated) {
            if (! empty($validated['is_primary'])) {
                Contact::where('lead_id', $lead->id)->update(['is_primary' => false]);
            }

            $contact = $this->createContact($validated);

            if ($contact->is_primary) {
                ActivityLogger::log('primary_contact_changed', "Primary contact changed to {$contact->name}", $lead);
            }

            return $contact;
        });

        ActivityLogger::log('contact_created', "Contact {$contact->name} created for lead {$lead->id}", $contact);

        return response()->json($contact->load('phones.lastCaller'), 201);
    }

    public function setPrimary(Request $request, Contact $contact): JsonResponse
    {
        Gate::authorize('update', $contact);

        $validated = $request->validate([
            'reason' => 'nullable|string|max:255',
        ]);

        DB::transaction(function () use ($contact, $validated) {
            $this->primaryScope($contact)->whereKeyNot($contact->id)->update(['is_primary' => false]);
            $contact->update([
                'is_primary' => true,
                'primary_reason' => $validated['reason'] ?? 'انتخاب دستی توسط کاربر',
            ]);
        });

        ActivityLogger::log('primary_contact_changed', "Primary contact changed to {$contact->name}", $contact->lead);

        return response()->json($contact->fresh('phones.lastCaller'));
    }

    public function update(Request $request, Contact $contact): JsonResponse
    {
        Gate::authorize('update', $contact);
        $validated = $this->validateContact($request, true);
        $this->authorizeParents($validated, 'update', $contact);
        DB::transaction(function () use ($contact, $validated, $request): void {
            $beforePhoneIds = $contact->phones()->withTrashed()->pluck('id')->all();
            $contact->update(collect($validated)->except('phones')->all());
            if ($contact->is_primary) {
                $this->primaryScope($contact)->whereKeyNot($contact->id)->update(['is_primary' => false]);
            }
            if ($request->has('phones')) {
                $keptIds = [];
                foreach ($validated['phones'] ?? [] as $phone) {
                    if (! empty($phone['id'])) {
                        $existing = $contact->phones()->withTrashed()->findOrFail($phone['id']);
                        $existing->restore();
                        $existing->update([
                            'phone' => $phone['phone'],
                            'type' => $phone['type'] ?? $existing->type,
                            'status' => $phone['status'] ?? 'active',
                        ]);
                        $keptIds[] = $existing->id;
                    } else {
                        $keptIds[] = ContactPhone::create([
                            'contact_id' => $contact->id,
                            'phone' => $phone['phone'],
                            'type' => $phone['type'] ?? 'mobile',
                            'status' => $phone['status'] ?? 'active',
                        ])->id;
                    }
                }
                $contact->phones()->whereNotIn('id', $keptIds)->get()->each(function (ContactPhone $phone): void {
                    $phone->update(['status' => 'inactive']);
                    $phone->delete();
                });
                ActivityLogger::log('contact_phones_updated', "Contact {$contact->id} phones updated", $contact, ['phone_ids' => $beforePhoneIds], ['phone_ids' => $keptIds]);
            }
        });
        ActivityLogger::log('contact_updated', "Contact {$contact->name} updated", $contact);

        return response()->json($contact->fresh('phones.lastCaller'));
    }

    public function destroy(Contact $contact): JsonResponse
    {
        Gate::authorize('delete', $contact);
        $contact->delete();
        ActivityLogger::log('contact_deleted', "Contact {$contact->id} deleted");

        return response()->json(['message' => 'مخاطب حذف شد']);
    }

    private function authorizeLeadAccess(Lead $lead): void
    {
        Gate::authorize('update', $lead);
    }

    private function authorizeParents(array $validated, string $ability, ?Contact $contact = null): void
    {
        $parentIds = [];
        foreach (['lead_id' => Lead::class, 'company_id' => Company::class, 'deal_id' => Deal::class] as $key => $model) {
            $parentIds[$key] = array_key_exists($key, $validated)
                ? $validated[$key]
                : $contact?->{$key};

            if (! empty($parentIds[$key])) {
                Gate::authorize($ability, $model::findOrFail($parentIds[$key]));
            }
        }

        $lead = $parentIds['lead_id'] ? Lead::findOrFail($parentIds['lead_id']) : null;
        $deal = $parentIds['deal_id'] ? Deal::findOrFail($parentIds['deal_id']) : null;
        $companyId = $parentIds['company_id'] ? (int) $parentIds['company_id'] : null;

        $incompatible = ($lead?->company_id && $companyId && (int) $lead->company_id !== $companyId)
            || ($deal?->company_id && $companyId && (int) $deal->company_id !== $companyId)
            || ($deal?->lead_id && $lead && (int) $deal->lead_id !== (int) $lead->id);

        if ($incompatible) {
            throw ValidationException::withMessages([
                'relationships' => 'شرکت، سرنخ و معامله انتخاب‌شده با یکدیگر سازگار نیستند.',
            ]);
        }
    }

    private function validateContact(Request $request, bool $partial = false): array
    {
        $sometimes = $partial ? 'sometimes|' : '';

        return $request->validate([
            'lead_id' => $sometimes.'nullable|exists:leads,id',
            'company_id' => $sometimes.'nullable|exists:companies,id',
            'deal_id' => $sometimes.'nullable|exists:deals,id',
            'name' => $sometimes.'required|string|max:255',
            'first_name' => 'nullable|string|max:120',
            'last_name' => 'nullable|string|max:120',
            'role' => 'nullable|string|max:80',
            'job_title' => 'nullable|string|max:120',
            'email' => 'nullable|email|max:255',
            'preferred_channel' => 'nullable|string|max:40',
            'description' => 'nullable|string',
            'status' => 'nullable|string|max:30',
            'is_primary' => 'nullable|boolean',
            'primary_reason' => 'nullable|string|max:255',
            'phones' => ($partial ? 'nullable' : 'required').'|array|min:1',
            'phones.*.phone' => 'required|string|max:30',
            'phones.*.id' => 'nullable|integer|exists:contact_phones,id',
            'phones.*.type' => 'nullable|string|in:mobile,landline,extension',
            'phones.*.status' => 'nullable|string|max:30',
        ]);
    }

    private function createContact(array $validated): Contact
    {
        $contact = Contact::create([
            'lead_id' => $validated['lead_id'] ?? null,
            'company_id' => $validated['company_id'] ?? null,
            'deal_id' => $validated['deal_id'] ?? null,
            'name' => $validated['name'],
            'first_name' => $validated['first_name'] ?? null,
            'last_name' => $validated['last_name'] ?? null,
            'role' => $validated['role'] ?? null,
            'job_title' => $validated['job_title'] ?? null,
            'email' => $validated['email'] ?? null,
            'preferred_channel' => $validated['preferred_channel'] ?? null,
            'description' => $validated['description'] ?? null,
            'status' => $validated['status'] ?? 'active',
            'is_primary' => (bool) ($validated['is_primary'] ?? false),
            'primary_reason' => $validated['primary_reason'] ?? (! empty($validated['is_primary']) ? 'انتخاب دستی توسط کاربر' : null),
            'created_by' => auth()->id(),
        ]);

        if ($contact->is_primary) {
            $this->primaryScope($contact)->whereKeyNot($contact->id)->update(['is_primary' => false]);
        }

        foreach ($validated['phones'] as $phone) {
            ContactPhone::create([
                'contact_id' => $contact->id,
                'phone' => $phone['phone'],
                'type' => $phone['type'] ?? 'mobile',
                'status' => $phone['status'] ?? 'active',
            ]);
        }

        return $contact;
    }

    private function primaryScope(Contact $contact)
    {
        $query = Contact::query();
        if ($contact->lead_id) {
            return $query->where('lead_id', $contact->lead_id);
        }
        if ($contact->company_id) {
            return $query->whereNull('lead_id')->where('company_id', $contact->company_id);
        }
        if ($contact->deal_id) {
            return $query->whereNull('lead_id')->whereNull('company_id')->where('deal_id', $contact->deal_id);
        }

        return $query->whereNull('lead_id')->whereNull('company_id')->whereNull('deal_id')->where('created_by', $contact->created_by);
    }
}