<?php

namespace App\Http\Controllers;

use App\Enums\SourceStatus;
use App\Http\Requests\StoreSourceRequest;
use App\Http\Requests\UpdateSourceRequest;
use App\Models\Depot;
use App\Models\Lieu;
use App\Models\Section;
use App\Models\Source;
use App\Models\SourceType;
use App\Models\User;
use App\Notifications\SourceAValiderNotification;
use App\Notifications\SourceRejeteeNotification;
use Illuminate\Http\RedirectResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;
use Illuminate\View\View;

class SourceController extends Controller
{
    public function index(Request $request): View
    {
        $this->authorize('viewAny', Source::class);

        $user = auth()->user();

        $query = Source::with(['sourceType', 'depot', 'lieu'])
            ->withCount('releves');

        if (! $user->isSectionManager()) {
            $assignedIds = $user->sourcesAssignees()->pluck('sources.id');
            $query->where(function ($q) use ($assignedIds) {
                $q->where('status', SourceStatus::Termine)
                  ->orWhereIn('id', $assignedIds);
            });
        }

        if ($request->filled('status')) {
            $query->where('status', $request->input('status'));
        }

        if ($request->filled('source_type_id')) {
            $query->where('source_type_id', $request->integer('source_type_id'));
        }

        if ($request->filled('lieu_id')) {
            $lieuIds = $this->getLieuDescendantIds($request->integer('lieu_id'));
            $query->whereIn('lieu_id', $lieuIds);
        }

        if ($request->filled('annee_debut')) {
            $annee = $request->integer('annee_debut');
            $query->where(function ($q) use ($annee) {
                $q->whereNull('annee_fin')->orWhere('annee_fin', '>=', $annee);
            });
        }

        if ($request->filled('annee_fin')) {
            $annee = $request->integer('annee_fin');
            $query->where(function ($q) use ($annee) {
                $q->whereNull('annee_debut')->orWhere('annee_debut', '<=', $annee);
            });
        }

        $sourceTypes     = SourceType::orderBy('nom')->get(['id', 'nom']);
        $lieuSelectionne = $request->filled('lieu_id')
            ? Lieu::find($request->integer('lieu_id'), ['id', 'nom', 'nom_long'])
            : null;

        $sources = $query->orderBy('nom')->paginate(25)->withQueryString();

        return view('sources.index', compact('sources', 'sourceTypes', 'lieuSelectionne'));
    }

    private function getLieuDescendantIds(int $lieuId): array
    {
        $rows = DB::select("
            WITH RECURSIVE descendants AS (
                SELECT id FROM lieux WHERE id = ?
                UNION ALL
                SELECT l.id FROM lieux l
                INNER JOIN descendants d ON l.lieu_parent_id = d.id
            )
            SELECT id FROM descendants
        ", [$lieuId]);

        return collect($rows)->pluck('id')->toArray();
    }

    public function create(): View
    {
        $this->authorize('create', Source::class);

        $user        = auth()->user();
        $sourceTypes = SourceType::orderBy('nom')->get(['id', 'nom']);
        $depots      = Depot::orderBy('nom')->get(['id', 'nom']);
        $sections    = $user->isAdmin()
            ? Section::orderBy('nom')->get(['id', 'nom'])
            : $user->sections()->orderBy('nom')->get(['id', 'nom']);

        return view('sources.create', compact('sourceTypes', 'depots', 'sections'));
    }

    public function store(StoreSourceRequest $request): RedirectResponse
    {
        $source = Source::create($request->validated());

        return redirect()->route('sources.show', $source)
            ->with('success', 'Source créée.');
    }

    public function show(Source $source): View
    {
        $this->authorize('view', $source);

        $source->load(['sourceType.fields', 'depot', 'section', 'membres', 'releves']);

        $availableUsers = User::where('is_active', true)->orderBy('name')->get(['id', 'name', 'email']);

        return view('sources.show', compact('source', 'availableUsers'));
    }

    public function edit(Source $source): View
    {
        $this->authorize('update', $source);

        $source->loadMissing('lieu', 'section');
        $user        = auth()->user();
        $sourceTypes = SourceType::orderBy('nom')->get(['id', 'nom']);
        $depots      = Depot::orderBy('nom')->get(['id', 'nom']);
        $sections    = $user->isAdmin()
            ? Section::orderBy('nom')->get(['id', 'nom'])
            : $user->sections()->orderBy('nom')->get(['id', 'nom']);

        return view('sources.edit', compact('source', 'sourceTypes', 'depots', 'sections'));
    }

    public function update(UpdateSourceRequest $request, Source $source): RedirectResponse
    {
        $source->update($request->validated());

        return redirect()->route('sources.show', $source)
            ->with('success', 'Source mise à jour.');
    }

    public function destroy(Source $source): RedirectResponse
    {
        $this->authorize('delete', $source);

        $source->delete();

        return redirect()->route('sources.index')
            ->with('success', 'Source supprimée.');
    }

    public function addMembre(Request $request, Source $source): RedirectResponse
    {
        $this->authorize('assignMembre', $source);

        $data = $request->validate([
            'user_id' => ['required', 'exists:users,id'],
        ]);

        $source->membres()->syncWithoutDetaching([$data['user_id']]);

        // Passer automatiquement en_cours si la source est à_faire
        if ($source->status === SourceStatus::AFaire) {
            $source->update(['status' => SourceStatus::EnCours]);
        }

        return back()->with('success', 'Membre assigné.');
    }

    public function removeMembre(Source $source, User $user): RedirectResponse
    {
        $this->authorize('assignMembre', $source);

        $source->membres()->detach($user->id);

        return back()->with('success', 'Membre retiré.');
    }

    public function transition(Request $request, Source $source): RedirectResponse
    {
        $this->authorize('transition', $source);

        $data = $request->validate([
            'status' => ['required', 'string'],
        ]);

        $newStatus = SourceStatus::from($data['status']);

        if (! $source->canTransitionTo($newStatus, auth()->user())) {
            return back()->with('error', 'Transition non autorisée.');
        }

        $previousStatus = $source->status;
        $source->update(['status' => $newStatus]);

        $user = auth()->user();

        if ($newStatus === SourceStatus::AValider) {
            // Notifier admins + responsables de section
            $source->load('sourceType', 'depot');
            User::whereIn('role', ['admin', 'section_manager'])
                ->where('id', '!=', $user->id)
                ->get()
                ->each(fn ($u) => $u->notify(new SourceAValiderNotification($source, $user)));
        }

        if ($newStatus === SourceStatus::EnCours && $previousStatus === SourceStatus::AValider) {
            // Rejet : notifier les membres assignés
            $source->membres()
                ->where('users.id', '!=', $user->id)
                ->get()
                ->each(fn ($m) => $m->notify(new SourceRejeteeNotification($source, $user)));
        }

        return back()->with('success', 'Statut mis à jour : ' . $newStatus->label());
    }
}