<?php

namespace App\Http\Controllers;

use App\Mail\ProjectInvitationMail;
use App\Models\Project;
use App\Models\ProjectInvitation;
use App\Models\User;
use Illuminate\Http\RedirectResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Mail;
use Illuminate\View\View;

class ProjectMemberController extends Controller
{
    /**
     * Display team members for a project
     */
    public function index(Project $project): View
    {
        $this->authorize('view', $project);

        $members = $project->users()
            ->withPivot('role', 'created_at')
            ->orderBy('project_user.created_at', 'desc')
            ->get();

        $pendingInvitations = $project->invitations()
            ->whereNull('accepted_at')
            ->where('expires_at', '>', now())
            ->with('inviter')
            ->orderBy('created_at', 'desc')
            ->get();

        return view('projects.members.index', [
            'project' => $project,
            'members' => $members,
            'pendingInvitations' => $pendingInvitations,
        ]);
    }

    /**
     * Invite a new member to the project
     */
    public function invite(Request $request, Project $project): RedirectResponse
    {
        $this->authorize('manageMembers', $project);

        $validated = $request->validate([
            'email' => 'required|email',
            'role' => 'required|in:member,admin',
        ]);

        // Check if user is already a member
        $existingUser = User::where('email', $validated['email'])->first();
        if ($existingUser && $project->users()->where('users.id', $existingUser->id)->exists()) {
            return back()->withErrors(['email' => 'This user is already a member of the project.']);
        }

        // Check if there's already a pending invitation
        $existingInvitation = $project->invitations()
            ->where('email', $validated['email'])
            ->whereNull('accepted_at')
            ->where('expires_at', '>', now())
            ->first();

        if ($existingInvitation) {
            return back()->withErrors(['email' => 'An invitation has already been sent to this email.']);
        }

        // Create invitation
        $invitation = $project->invitations()->create([
            'email' => $validated['email'],
            'role' => $validated['role'],
            'invited_by' => auth()->id(),
        ]);

        // Send invitation email
        Mail::to($invitation->email)->send(new ProjectInvitationMail($invitation));

        return back()->with('success', 'Invitation sent successfully.');
    }

    /**
     * Accept an invitation
     */
    public function acceptInvitation(string $token): RedirectResponse
    {
        $invitation = ProjectInvitation::where('token', $token)->firstOrFail();

        if ($invitation->isExpired()) {
            return redirect()->route('dashboard')->withErrors(['error' => 'This invitation has expired.']);
        }

        if ($invitation->accepted_at) {
            return redirect()->route('dashboard')->withErrors(['error' => 'This invitation has already been accepted.']);
        }

        // Check if the logged-in user's email matches
        if (auth()->user()->email !== $invitation->email) {
            return redirect()->route('dashboard')->withErrors(['error' => 'This invitation was sent to a different email address.']);
        }

        $invitation->accept(auth()->user());

        return redirect()->route('projects.issues.index', $invitation->project)
            ->with('success', 'You have joined the project successfully.');
    }

    /**
     * Update a member's role
     */
    public function updateRole(Request $request, Project $project, User $user): RedirectResponse
    {
        $this->authorize('manageMembers', $project);

        $validated = $request->validate([
            'role' => 'required|in:member,admin,owner',
        ]);

        // Don't allow changing your own role
        if ($user->id === auth()->id()) {
            return back()->withErrors(['error' => 'You cannot change your own role.']);
        }

        // Check if user is a member of the project
        if (!$project->users()->where('users.id', $user->id)->exists()) {
            return back()->withErrors(['error' => 'User is not a member of this project.']);
        }

        $project->users()->updateExistingPivot($user->id, ['role' => $validated['role']]);

        return back()->with('success', 'Member role updated successfully.');
    }

    /**
     * Remove a member from the project
     */
    public function destroy(Project $project, User $user): RedirectResponse
    {
        $this->authorize('manageMembers', $project);

        // Don't allow removing yourself
        if ($user->id === auth()->id()) {
            return back()->withErrors(['error' => 'You cannot remove yourself from the project.']);
        }

        // Check if user is a member
        if (!$project->users()->where('users.id', $user->id)->exists()) {
            return back()->withErrors(['error' => 'User is not a member of this project.']);
        }

        $project->users()->detach($user->id);

        return back()->with('success', 'Member removed from project successfully.');
    }

    /**
     * Cancel a pending invitation
     */
    public function cancelInvitation(Project $project, ProjectInvitation $invitation): RedirectResponse
    {
        $this->authorize('manageMembers', $project);

        if ($invitation->project_id !== $project->id) {
            abort(404);
        }

        $invitation->delete();

        return back()->with('success', 'Invitation cancelled successfully.');
    }
}