<?php

namespace App\Http\Controllers;

use App\Models\Letter;
use App\Models\LetterAttachment;
use App\Models\Project;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\Storage;

class LetterController extends Controller
{
    /**
     * Display a listing of letters with filters.
     */
    public function index(Request $request)
    {
        $this->authorize('viewAny', Letter::class);

        $query = Letter::with(['project', 'attachments']);

        if ($request->filled('type')) {
            $query->byType($request->type);
        }

        if ($request->filled('status')) {
            $query->byStatus($request->status);
        }

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

        if ($request->filled('search')) {
            $query->search($request->search);
        }

        $letters = $query->orderBy('letter_date', 'desc')
            ->orderBy('created_at', 'desc')
            ->paginate(20)
            ->appends($request->query());

        $projects = Project::all();
        $types = ['incoming', 'outgoing'];
        $statuses = ['draft', 'sent', 'received', 'archived'];

        return view('letters.index', compact('letters', 'projects', 'types', 'statuses'));
    }

    /**
     * Show the form for creating a new letter.
     */
    public function create(Request $request)
    {
        $this->authorize('create', Letter::class);

        $projects = Project::all();
        $letters = Letter::orderBy('letter_date', 'desc')->limit(50)->get();
        $letter = null;

        // Pre-fill parent_letter_id if provided
        $preselectedParent = $request->get('parent_letter_id');

        return view('letters.form', compact('projects', 'letters', 'letter', 'preselectedParent'));
    }

    /**
     * Store a newly created letter in storage.
     */
    public function store(Request $request)
    {
        $this->authorize('create', Letter::class);

        $validated = $request->validate([
            'type' => 'required|in:incoming,outgoing',
            'subject' => 'required|string|max:255',
            'sender' => 'required|string|max:255',
            'recipient' => 'required|string|max:255',
            'letter_date' => 'required|date',
            'reference_number' => 'nullable|string|max:100',
            'project_id' => 'nullable|exists:projects,id',
            'parent_letter_id' => 'nullable|exists:letters,id',
            'status' => 'required|in:draft,sent,received,archived',
            'content' => 'nullable|string',
            'attachments.*' => 'nullable|file|mimes:jpg,jpeg,png,pdf|max:10240',
        ]);

        // Convert jalali date if needed
        if (!empty($validated['letter_date'])) {
            $validated['letter_date'] = \App\Helpers\CalendarHelper::parseDate($validated['letter_date']);
        }

        $validated['tenant_id'] = $this->getTenantId();

        $letter = Letter::create($validated);

        // Handle file attachments
        if ($request->hasFile('attachments')) {
            foreach ($request->file('attachments') as $file) {
                $this->storeAttachment($letter, $file);
            }
        }

        // Remove checked attachments (for edit, but safe to check)
        if ($request->has('remove_attachments')) {
            foreach ($request->remove_attachments as $attachmentId) {
                $this->removeAttachment($attachmentId, $letter);
            }
        }

        return redirect()
            ->route('letters.show', $letter)
            ->with('success', __('letter.created_successfully'));
    }

    /**
     * Display the specified letter.
     */
    public function show(Letter $letter)
    {
        $this->authorize('view', $letter);

        $letter->load(['project', 'parentLetter', 'replies', 'attachments']);

        return view('letters.show', compact('letter'));
    }

    /**
     * Show the form for editing the specified letter.
     */
    public function edit(Letter $letter)
    {
        $this->authorize('update', $letter);

        $letter->load('attachments');

        $projects = Project::all();
        $letters = Letter::where('id', '!=', $letter->id)
            ->orderBy('letter_date', 'desc')
            ->limit(50)
            ->get();

        return view('letters.form', compact('letter', 'projects', 'letters'));
    }

    /**
     * Update the specified letter in storage.
     */
    public function update(Request $request, Letter $letter)
    {
        $this->authorize('update', $letter);

        $validated = $request->validate([
            'type' => 'required|in:incoming,outgoing',
            'subject' => 'required|string|max:255',
            'sender' => 'required|string|max:255',
            'recipient' => 'required|string|max:255',
            'letter_date' => 'required|date',
            'reference_number' => 'nullable|string|max:100',
            'project_id' => 'nullable|exists:projects,id',
            'parent_letter_id' => 'nullable|exists:letters,id',
            'status' => 'required|in:draft,sent,received,archived',
            'content' => 'nullable|string',
            'attachments.*' => 'nullable|file|mimes:jpg,jpeg,png,pdf|max:10240',
        ]);

        // Convert jalali date if needed
        if (!empty($validated['letter_date'])) {
            $validated['letter_date'] = \App\Helpers\CalendarHelper::parseDate($validated['letter_date']);
        }

        $letter->update($validated);

        // Handle file attachments
        if ($request->hasFile('attachments')) {
            foreach ($request->file('attachments') as $file) {
                $this->storeAttachment($letter, $file);
            }
        }

        // Remove checked attachments
        if ($request->has('remove_attachments')) {
            foreach ($request->remove_attachments as $attachmentId) {
                $this->removeAttachment($attachmentId, $letter);
            }
        }

        return redirect()
            ->route('letters.show', $letter)
            ->with('success', __('letter.updated_successfully'));
    }

    /**
     * Remove the specified letter from storage.
     */
    public function destroy(Letter $letter)
    {
        $this->authorize('delete', $letter);

        // Delete attachments from storage
        foreach ($letter->attachments as $attachment) {
            Storage::disk('public')->delete($attachment->file_path);
        }

        $letter->delete();

        return redirect()
            ->route('letters.index')
            ->with('success', __('letter.deleted_successfully'));
    }

    /**
     * Archive the specified letter.
     */
    public function archive(Letter $letter)
    {
        $this->authorize('update', $letter);

        $letter->update(['status' => 'archived']);

        return response()->json([
            'success' => true,
            'message' => __('letter.archived_successfully'),
        ]);
    }

    /**
     * Store a file attachment for a letter.
     */
    private function storeAttachment(Letter $letter, $file): void
    {
        $path = $file->store('letters/' . $letter->id, 'public');

        LetterAttachment::create([
            'letter_id' => $letter->id,
            'file_name' => $file->getClientOriginalName(),
            'file_path' => $path,
            'file_size' => $file->getSize(),
            'mime_type' => $file->getMimeType(),
        ]);
    }

    /**
     * Remove a letter attachment.
     */
    private function removeAttachment(int $attachmentId, Letter $letter): void
    {
        $attachment = LetterAttachment::where('id', $attachmentId)
            ->where('letter_id', $letter->id)
            ->first();

        if ($attachment) {
            Storage::disk('public')->delete($attachment->file_path);
            $attachment->delete();
        }
    }
}