<?php

declare(strict_types=1);

namespace WordPress\CloudflareWorkersAiProvider\Routing;

use WordPress\CloudflareWorkersAiProvider\Gateway;
use WordPress\CloudflareWorkersAiProvider\Usage\UsageTracker;

use function WordPress\CloudflareWorkersAiProvider\get_default_model_id;
use function WordPress\CloudflareWorkersAiProvider\get_plugin_settings;
use function WordPress\CloudflareWorkersAiProvider\pretty_model_name;
use function WordPress\CloudflareWorkersAiProvider\task_label;
use function WordPress\CloudflareWorkersAiProvider\vision_model_id;

if (!defined('ABSPATH')) {
    exit;
}

/**
 * Which model answers which kind of request on this site, in the same terms the
 * routing code uses, so the settings screens never claim one model while the
 * logs show another.
 */
final class ModelMap
{
    /**
     * The text model a task slug is sent to under normal conditions.
     */
    public static function textModelFor(string $task): string
    {
        $settings = get_plugin_settings();
        $light    = trim((string) ($settings['light_model'] ?? ''));
        $tasks    = isset($settings['light_tasks']) && is_array($settings['light_tasks'])
            ? array_map('sanitize_key', $settings['light_tasks'])
            : TaskContext::DEFAULT_LIGHT_TASKS;
        if ($light !== '' && in_array(TaskContext::baseTask(sanitize_key($task)), $tasks, true)) {
            return $light;
        }
        return get_default_model_id();
    }

    /**
     * Rows of [what, model name, note], plain text.
     *
     * @return list<array{0: string, 1: string, 2: string}>
     */
    public static function rows(): array
    {
        $settings = get_plugin_settings();
        $light    = trim((string) ($settings['light_model'] ?? ''));
        $tasks    = isset($settings['light_tasks']) && is_array($settings['light_tasks']) ? $settings['light_tasks'] : TaskContext::DEFAULT_LIGHT_TASKS;
        $labels   = array_map(static fn($t): string => task_label((string) $t), array_slice($tasks, 0, 4));
        $rows     = [];

        if (Gateway::compatMode()) {
            $rows[] = [
                __('Writing and short tasks', 'aipcf-ai-provider-for-cloudflare'),
                /* translators: %s: dynamic route name */
                sprintf(__('Gateway route "%s"', 'aipcf-ai-provider-for-cloudflare'), Gateway::dynamicRoute()),
                __('The AI Gateway dynamic route picks the model; the models below apply only to image requests.', 'aipcf-ai-provider-for-cloudflare'),
            ];
        } else {
            $rows[] = [
                __('Writing (drafts, summaries, anything not listed below)', 'aipcf-ai-provider-for-cloudflare'),
                pretty_model_name(get_default_model_id()),
                __('Default text model.', 'aipcf-ai-provider-for-cloudflare'),
            ];
            $rows[] = [
                __('Short tasks', 'aipcf-ai-provider-for-cloudflare'),
                $light !== '' ? pretty_model_name($light) : pretty_model_name(get_default_model_id()),
                $light !== '' && $tasks !== []
                    ? sprintf(
                        /* translators: %s: list of tasks */
                        __('Light model, for: %s. A model picked for a feature in the AI plugin is used as picked.', 'aipcf-ai-provider-for-cloudflare'),
                        count($tasks) > 4
                            ? sprintf(
                                /* translators: 1: first task names, 2: how many more tasks */
                                _n('%1$s and %2$d more task', '%1$s and %2$d more tasks', count($tasks) - 4, 'aipcf-ai-provider-for-cloudflare'),
                                implode(', ', $labels),
                                count($tasks) - 4
                            )
                            : implode(', ', $labels)
                    )
                    : __('Light model is off, so the default model answers.', 'aipcf-ai-provider-for-cloudflare'),
            ];
        }
        $rows[] = [
            __('Reading images (alt text, image descriptions)', 'aipcf-ai-provider-for-cloudflare'),
            pretty_model_name(vision_model_id()),
            __('Vision model. Text models cannot see images, so this is the only one used for them.', 'aipcf-ai-provider-for-cloudflare'),
        ];
        $rows[] = [
            __('Generating images', 'aipcf-ai-provider-for-cloudflare'),
            pretty_model_name((string) (($settings['image_model'] ?? '') ?: '@cf/black-forest-labs/flux-1-schnell')),
            __('Image model.', 'aipcf-ai-provider-for-cloudflare'),
        ];
        // Translation has no screen of its own: it runs only when a theme or plugin calls
        // aipcf_translate(), so the row shows only once that has happened recently.
        if (self::translationUsed()) {
            $rows[] = [
                __('Translation', 'aipcf-ai-provider-for-cloudflare'),
                'M2M100 / IndicTrans2',
                __('Used when a theme or plugin calls aipcf_translate(): IndicTrans2 for Indian languages, M2M100 for the rest.', 'aipcf-ai-provider-for-cloudflare'),
            ];
        }
        if (UsageTracker::budgetEnabled()) {
            $rows[] = [
                __('After the daily budget is used up', 'aipcf-ai-provider-for-cloudflare'),
                UsageTracker::budgetAction() === 'cheapest' ? pretty_model_name(UsageTracker::cheapestTextModelId()) : __('Paused', 'aipcf-ai-provider-for-cloudflare'),
                UsageTracker::budgetAction() === 'cheapest'
                    ? __('Text requests switch to the cheapest model; Backfill, the content index, Link assistant chat, the Site assistant, Search, Search insights, image generation, image reading and translation pause until midnight UTC.', 'aipcf-ai-provider-for-cloudflare')
                    : __('All requests pause until midnight UTC.', 'aipcf-ai-provider-for-cloudflare'),
            ];
        }
        return $rows;
    }

    /**
     * Whether a translation model answered any request in the last 30 days (the usage history
     * keeps requests per model per day).
     */
    public static function translationUsed(int $days = 30): bool
    {
        $since = gmdate('Y-m-d', time() - $days * DAY_IN_SECONDS);
        foreach (UsageTracker::all() as $day => $entry) {
            if ((string) $day < $since || !is_array($entry)) {
                continue;
            }
            foreach (array_keys((array) ($entry['models'] ?? [])) as $model) {
                if (\WordPress\CloudflareWorkersAiProvider\Models\CloudflareWorkersAiTranslationModel::supports((string) $model)) {
                    return true;
                }
            }
        }
        return false;
    }
}