<?php

/**
 * @author  Ball Studios <https://git.balls.studio>
 * @license MIT
 */

namespace Pterodactyl\Addons\AdvancedAdmin\Services\Roles;

use Illuminate\Validation\ValidationException;
use Pterodactyl\Addons\AdvancedAdmin\Models\Role;
use Pterodactyl\Addons\AdvancedAdmin\Models\RoleAuditLog;
use Pterodactyl\Addons\AdvancedAdmin\Models\RolePermission;
use Pterodactyl\Addons\AdvancedAdmin\Models\ServerPermissionOverride;
use Pterodactyl\Addons\AdvancedAdmin\Models\ServerRoleAssignment;
use Illuminate\Support\Facades\DB;

class RoleService
{
    /**
     * All known Pterodactyl permission keys (validated against).
     */
    public const KNOWN_PERMISSIONS = [
        'websocket.connect',
        'control.console', 'control.start', 'control.stop', 'control.restart',
        'user.read', 'user.create', 'user.update', 'user.delete',
        'file.read', 'file.read-content', 'file.create', 'file.update',
        'file.delete', 'file.archive', 'file.sftp',
        'backup.read', 'backup.create', 'backup.delete', 'backup.download', 'backup.restore',
        'allocation.read', 'allocation.create', 'allocation.update', 'allocation.delete',
        'startup.read', 'startup.update', 'startup.docker-image',
        'database.read', 'database.create', 'database.update', 'database.delete', 'database.view-password',
        'schedule.read', 'schedule.create', 'schedule.update', 'schedule.delete',
        'settings.read', 'settings.rename', 'settings.reinstall',
        'activity.read',
    ];

    public function create(array $data, int $actorId): Role
    {
        return DB::transaction(function () use ($data, $actorId) {
            $role = Role::create([
                'name'        => $data['name'],
                'description' => $data['description'] ?? null,
                'color'       => $data['color'] ?? '#6366f1',
                'priority'    => $data['priority'] ?? 0,
                'is_default'  => $data['is_default'] ?? false,
                'created_by'  => $actorId,
            ]);

            if (!empty($data['permissions'])) {
                $this->syncPermissions($role, $data['permissions'], $actorId);
            }

            RoleAuditLog::record($actorId, 'role.create', 'role', $role->id, ['name' => $role->name]);
            return $role;
        });
    }

    public function update(Role $role, array $data, int $actorId): Role
    {
        return DB::transaction(function () use ($role, $data, $actorId) {
            $role->update(array_filter([
                'name'        => $data['name'] ?? null,
                'description' => $data['description'] ?? null,
                'color'       => $data['color'] ?? null,
                'priority'    => $data['priority'] ?? null,
                'is_default'  => $data['is_default'] ?? null,
            ], fn ($v) => $v !== null));

            if (isset($data['permissions'])) {
                $this->syncPermissions($role, $data['permissions'], $actorId);
            }

            RoleAuditLog::record($actorId, 'role.update', 'role', $role->id, $data);
            return $role->refresh();
        });
    }

    public function delete(Role $role, int $actorId, bool $force = false): void
    {
        if ($role->isInUse() && !$force) {
            throw ValidationException::withMessages([
                'role' => ['This role is still assigned to users. Pass force=true to delete anyway.'],
            ]);
        }

        DB::transaction(function () use ($role, $actorId) {
            RoleAuditLog::record($actorId, 'role.delete', 'role', $role->id, ['name' => $role->name]);
            $role->delete();
        });
    }

    public function syncPermissions(Role $role, array $permissions, int $actorId): void
    {
        // Validate all permission names
        $invalid = array_diff(array_keys($permissions), self::KNOWN_PERMISSIONS);
        if (!empty($invalid)) {
            throw ValidationException::withMessages([
                'permissions' => ['Unknown permissions: ' . implode(', ', $invalid)],
            ]);
        }

        DB::transaction(function () use ($role, $permissions, $actorId) {
            $role->permissions()->delete();
            foreach ($permissions as $perm => $value) {
                if (!in_array($value, ['allow', 'deny'], true)) continue;
                RolePermission::create([
                    'role_id'    => $role->id,
                    'permission' => $perm,
                    'value'      => $value,
                ]);
            }
            RoleAuditLog::record($actorId, 'role.permissions_updated', 'role', $role->id, ['permissions' => $permissions]);
        });
    }

    public function assignToUser(int $serverId, int $userId, int $roleId, int $actorId): ServerRoleAssignment
    {
        // Prevent privilege escalation: actor's max role priority must be >= target role priority
        $targetRole   = Role::findOrFail($roleId);
        $actorMaxPrio = $this->getMaxPriorityForUser($actorId, $serverId);

        if ($targetRole->priority > $actorMaxPrio) {
            throw ValidationException::withMessages([
                'role' => ['You cannot assign a role with higher priority than your own.'],
            ]);
        }

        $assignment = ServerRoleAssignment::firstOrCreate([
            'server_id'   => $serverId,
            'user_id'     => $userId,
            'role_id'     => $roleId,
        ], [
            'assigned_by' => $actorId,
        ]);

        RoleAuditLog::record($actorId, 'role.assign', 'user', $userId, [
            'server_id' => $serverId,
            'role_id'   => $roleId,
            'role_name' => $targetRole->name,
        ]);

        return $assignment;
    }

    public function unassignFromUser(int $serverId, int $userId, int $roleId, int $actorId): void
    {
        ServerRoleAssignment::query()
            ->where('server_id', $serverId)
            ->where('user_id', $userId)
            ->where('role_id', $roleId)
            ->delete();

        RoleAuditLog::record($actorId, 'role.unassign', 'user', $userId, [
            'server_id' => $serverId,
            'role_id'   => $roleId,
        ]);
    }

    public function setOverride(
        int    $serverId,
        int    $userId,
        string $permission,
        string $value,
        int    $actorId
    ): ServerPermissionOverride {
        if (!in_array($permission, self::KNOWN_PERMISSIONS, true)) {
            throw ValidationException::withMessages(['permission' => ['Unknown permission key.']]);
        }
        if (!in_array($value, ['allow', 'deny', 'unset'], true)) {
            throw ValidationException::withMessages(['value' => ['Value must be allow, deny, or unset.']]);
        }

        $override = ServerPermissionOverride::updateOrCreate(
            ['server_id' => $serverId, 'user_id' => $userId, 'permission' => $permission],
            ['value'     => $value, 'set_by' => $actorId]
        );

        RoleAuditLog::record($actorId, 'override.set', 'user', $userId, [
            'server_id'  => $serverId,
            'permission' => $permission,
            'value'      => $value,
        ]);

        return $override;
    }

    private function getMaxPriorityForUser(int $userId, int $serverId): int
    {
        // If admin, return PHP_INT_MAX
        $user = \Pterodactyl\Models\User::find($userId);
        if ($user && $user->root_admin) return PHP_INT_MAX;

        return ServerRoleAssignment::query()
            ->where('server_id', $serverId)
            ->where('user_id', $userId)
            ->with('role')
            ->get()
            ->max(fn ($a) => $a->role->priority ?? 0) ?? 0;
    }
}