<?php

namespace App\Services\AiEditing;

use App\Models\AiStyle;
use App\Models\Event;
use Illuminate\Support\Arr;
use Illuminate\Support\Collection;

class EventAiEditingPolicyService
{
    /**
     * @return array{
     *     enabled: bool,
     *     allow_custom_prompt: bool,
     *     allowed_style_keys: array<int, string>,
     *     policy_message: ?string
     * }
     */
    public function resolve(Event $event): array
    {
        $settings = is_array($event->settings) ? $event->settings : [];
        $aiSettings = Arr::get($settings, 'ai_editing', []);
        $aiSettings = is_array($aiSettings) ? $aiSettings : [];

        $enabled = array_key_exists('enabled', $aiSettings)
            ? (bool) $aiSettings['enabled']
            : true;
        $allowCustomPrompt = array_key_exists('allow_custom_prompt', $aiSettings)
            ? (bool) $aiSettings['allow_custom_prompt']
            : true;

        $allowedStyleKeys = collect($aiSettings['allowed_style_keys'] ?? [])
            ->filter(fn (mixed $value): bool => is_string($value) && trim($value) !== '')
            ->map(fn (string $value): string => trim($value))
            ->unique()
            ->values()
            ->all();

        $policyMessage = trim((string) ($aiSettings['policy_message'] ?? ''));

        return [
            'enabled' => $enabled,
            'allow_custom_prompt' => $allowCustomPrompt,
            'allowed_style_keys' => $allowedStyleKeys,
            'policy_message' => $policyMessage !== '' ? $policyMessage : null,
        ];
    }

    public function isEnabled(Event $event): bool
    {
        return (bool) $this->resolve($event)['enabled'];
    }

    public function isStyleAllowed(Event $event, ?AiStyle $style): bool
    {
        $policy = $this->resolve($event);

        if ($style === null) {
            return (bool) $policy['allow_custom_prompt'];
        }

        /** @var array<int, string> $allowedStyleKeys */
        $allowedStyleKeys = $policy['allowed_style_keys'];
        if ($allowedStyleKeys === []) {
            return true;
        }

        return in_array($style->key, $allowedStyleKeys, true);
    }

    /**
     * @param  Collection<int, AiStyle>  $styles
     * @return Collection<int, AiStyle>
     */
    public function filterStyles(Event $event, Collection $styles): Collection
    {
        $policy = $this->resolve($event);

        /** @var array<int, string> $allowedStyleKeys */
        $allowedStyleKeys = $policy['allowed_style_keys'];
        if ($allowedStyleKeys === []) {
            return $styles->values();
        }

        return $styles
            ->filter(fn (AiStyle $style): bool => in_array($style->key, $allowedStyleKeys, true))
            ->values();
    }
}