<?php

namespace App\Services;

use App\Models\Article;
use App\Models\ArticlePublication;
use Carbon\Carbon;
use Illuminate\Support\Facades\DB;

class DashboardStatsService
{
    /**
     * @return array
     */
    public function getStats(string $period = 'today'): array
    {
        $dateRange = $this->getDateRange($period);
        
        // Get articles fetched for the period
        $articlesFetchedQuery = Article::query();
        if ($dateRange) {
            $articlesFetchedQuery->whereBetween('created_at', $dateRange);
        }
        $articlesFetched = $articlesFetchedQuery->count();

        // Get articles published for the period
        $articlesPublishedQuery = ArticlePublication::query()
            ->whereNotNull('published_at');
        if ($dateRange) {
            $articlesPublishedQuery->whereBetween('published_at', $dateRange);
        }
        $articlesPublished = $articlesPublishedQuery->count();

        // Calculate published percentage
        $publishedPercentage = $articlesFetched > 0 ? round(($articlesPublished / $articlesFetched) * 100, 1) : 0.0;

        return [
            'articles_fetched' => $articlesFetched,
            'articles_published' => $articlesPublished,
            'published_percentage' => $publishedPercentage,
        ];
    }

    /**
     * @return array<string, string>
     */
    public function getAvailablePeriods(): array
    {
        return [
            'today' => 'Today',
            'week' => 'This Week',
            'month' => 'This Month',
            'year' => 'This Year',
            'all' => 'All Time',
        ];
    }

    /**
     * @return array{0: Carbon, 1: Carbon}|null
     */
    private function getDateRange(string $period): ?array
    {
        $now = Carbon::now();
        
        return match ($period) {
            'today' => [$now->copy()->startOfDay(), $now->copy()->endOfDay()],
            'week' => [$now->copy()->startOfWeek(), $now->copy()->endOfWeek()],
            'month' => [$now->copy()->startOfMonth(), $now->copy()->endOfMonth()],
            'year' => [$now->copy()->startOfYear(), $now->copy()->endOfYear()],
            'all' => null, // No date filtering for all-time stats
            default => [$now->copy()->startOfDay(), $now->copy()->endOfDay()],
        };
    }

    /**
     * Get additional stats for dashboard
     */
    public function getSystemStats(): array
    {
        // Optimize with single queries using conditional aggregation
        $feedStats = DB::table('feeds')
            ->selectRaw('
                COUNT(*) as total_feeds,
                SUM(CASE WHEN is_active = 1 THEN 1 ELSE 0 END) as active_feeds
            ')
            ->first();
            
        $accountStats = DB::table('platform_accounts')
            ->selectRaw('
                COUNT(*) as total_platform_accounts,
                SUM(CASE WHEN is_active = 1 THEN 1 ELSE 0 END) as active_platform_accounts
            ')
            ->first();
            
        $channelStats = DB::table('platform_channels')
            ->selectRaw('
                COUNT(*) as total_platform_channels,
                SUM(CASE WHEN is_active = 1 THEN 1 ELSE 0 END) as active_platform_channels
            ')
            ->first();
            
        $routeStats = DB::table('routes')
            ->selectRaw('
                COUNT(*) as total_routes,
                SUM(CASE WHEN is_active = 1 THEN 1 ELSE 0 END) as active_routes
            ')
            ->first();
            
        return [
            'total_feeds' => $feedStats->total_feeds,
            'active_feeds' => $feedStats->active_feeds,
            'total_platform_accounts' => $accountStats->total_platform_accounts,
            'active_platform_accounts' => $accountStats->active_platform_accounts,
            'total_platform_channels' => $channelStats->total_platform_channels,
            'active_platform_channels' => $channelStats->active_platform_channels,
            'total_routes' => $routeStats->total_routes,
            'active_routes' => $routeStats->active_routes,
        ];
    }
}