<?php

namespace App\Http\Controllers;

use App\Models\ForumThread;
use App\Models\ForumTopic;
use App\Models\ForumPost;
use Illuminate\Http\Request;

class ForumTopicController extends Controller
{
    /**
     * Display a listing of the resource.
     */
    public function index()
    {
        // Not needed as topics are displayed within threads
        return redirect()->route('forum.index');
    }

    /**
     * Show the form for creating a new resource.
     */
    public function create(Request $request)
    {
        $thread_id = $request->query('thread_id');
        if (!$thread_id) {
            return redirect()->route('forum.index')
                ->with('error', 'Thread ID is required to create a topic.');
        }

        $thread = ForumThread::findOrFail($thread_id);

        // Check if thread is locked
        if ($thread->is_locked) {
            return redirect()->route('forum.threads.show', $thread)
                ->with('error', 'This thread is locked. You cannot create new topics.');
        }

        return view('forum.topics.create', compact('thread'));
    }

    /**
     * Store a newly created resource in storage.
     */
    public function store(Request $request)
    {
        $validated = $request->validate([
            'title' => 'required|string|max:255',
            'content' => 'required|string',
            'thread_id' => 'required|exists:forum_threads,id',
        ]);

        $thread = ForumThread::findOrFail($validated['thread_id']);

        // Check if thread is locked
        if ($thread->is_locked) {
            return redirect()->route('forum.threads.show', $thread)
                ->with('error', 'This thread is locked. You cannot create new topics.');
        }

        // Create the topic
        $topic = new ForumTopic();
        $topic->thread_id = $validated['thread_id'];
        $topic->user_id = auth()->id();
        $topic->title = $validated['title'];
        $topic->content = $validated['content'];
        $topic->last_activity_at = now();
        $topic->save();

        // Update thread's last activity
        $thread->last_activity_at = now();
        $thread->save();

        return redirect()->route('forum.topics.show', $topic)
            ->with('success', 'Topic created successfully.');
    }

    /**
     * Display the specified resource.
     */
    public function show(ForumTopic $topic)
    {
        $thread = $topic->thread;

        // Get posts with pagination
        $posts = $topic->posts()
            ->with('user')
            ->orderBy('created_at', 'asc')
            ->paginate(15);

        return view('forum.topics.show', compact('topic', 'thread', 'posts'));
    }

    /**
     * Show the form for editing the specified resource.
     */
    public function edit(ForumTopic $topic)
    {
        // Check if user is authorized to edit this topic
        if (auth()->id() !== $topic->user_id && !auth()->user()->hasRole('admin')) {
            return redirect()->route('forum.topics.show', $topic)
                ->with('error', 'You are not authorized to edit this topic.');
        }

        $thread = $topic->thread;

        // Check if thread is locked
        if ($thread->is_locked) {
            return redirect()->route('forum.topics.show', $topic)
                ->with('error', 'This thread is locked. You cannot edit topics.');
        }

        return view('forum.topics.edit', compact('topic', 'thread'));
    }

    /**
     * Update the specified resource in storage.
     */
    public function update(Request $request, ForumTopic $topic)
    {
        // Check if user is authorized to edit this topic
        if (auth()->id() !== $topic->user_id && !auth()->user()->hasRole('admin')) {
            return redirect()->route('forum.topics.show', $topic)
                ->with('error', 'You are not authorized to edit this topic.');
        }

        $thread = $topic->thread;

        // Check if thread is locked
        if ($thread->is_locked) {
            return redirect()->route('forum.topics.show', $topic)
                ->with('error', 'This thread is locked. You cannot edit topics.');
        }

        $validated = $request->validate([
            'title' => 'required|string|max:255',
            'content' => 'required|string',
        ]);

        // Update the topic
        $topic->title = $validated['title'];
        $topic->content = $validated['content'];
        $topic->save();

        return redirect()->route('forum.topics.show', $topic)
            ->with('success', 'Topic updated successfully.');
    }

    /**
     * Remove the specified resource from storage.
     */
    public function destroy(ForumTopic $topic)
    {
        // Check if user is authorized to delete this topic
        if (auth()->id() !== $topic->user_id && !auth()->user()->hasRole('admin')) {
            return redirect()->route('forum.topics.show', $topic)
                ->with('error', 'You are not authorized to delete this topic.');
        }

        $thread = $topic->thread;

        // Check if thread is locked
        if ($thread->is_locked) {
            return redirect()->route('forum.topics.show', $topic)
                ->with('error', 'This thread is locked. You cannot delete topics.');
        }

        // Check if this is the only topic in the thread
        if ($thread->topics()->count() <= 1) {
            return redirect()->route('forum.topics.show', $topic)
                ->with('error', 'Cannot delete the only topic in a thread. Delete the thread instead.');
        }

        $topic->delete();

        return redirect()->route('forum.threads.show', $thread)
            ->with('success', 'Topic deleted successfully.');
    }
}