<?php

namespace App\Services\Finance;

class FinancialChartService
{
    public function generateBarChart(array $summary): ?string
    {
        if ($this->skipRemoteCharts()) {
            return null;
        }

        $chartData = [
            'type' => 'bar',
            'data' => [
                'labels' => ['Charges', 'Paid', 'Unpaid', 'Discounts', 'Refunds', 'Expenses', 'Reimbursements', 'Net'],
                'datasets' => [[
                    'label' => 'Amount (USD)',
                    'data' => [
                        $summary['totalCharges'] ?? 0,
                        $summary['amountCollected'] ?? 0,
                        $summary['totalUnpaid'] ?? 0,
                        $summary['totalDiscounts'] ?? 0,
                        $summary['totalRefunds'] ?? 0,
                        $summary['totalExpenses'] ?? 0,
                        $summary['totalReimbursements'] ?? 0,
                        $summary['netAmount'] ?? 0,
                    ],
                    'backgroundColor' => 'rgba(54, 162, 235, 0.6)',
                ]],
            ],
        ];

        return $this->downloadChart($chartData, 'bar_chart.png');
    }

    public function generatePieChart(array $summary): ?string
    {
        if ($this->skipRemoteCharts()) {
            return null;
        }

        $chartData = [
            'type' => 'pie',
            'data' => [
                'labels' => ['Expenses', 'Reimbursements'],
                'datasets' => [[
                    'data' => [
                        $summary['totalExpenses'] ?? 0,
                        $summary['totalReimbursements'] ?? 0,
                    ],
                    'backgroundColor' => ['#e74c3c', '#8e44ad'],
                ]],
            ],
        ];

        return $this->downloadChart($chartData, 'pie_chart.png');
    }

    private function downloadChart(array $chartData, string $filename): ?string
    {
        $baseUrl = 'https://quickchart.io/chart?c=';
        $url = $baseUrl . urlencode(json_encode($chartData));
        $targetDir = storage_path('app/reports');
        if (!is_dir($targetDir) && !mkdir($targetDir, 0775, true) && !is_dir($targetDir)) {
            return null;
        }

        try {
            $contents = @file_get_contents($url);
            if ($contents === false) {
                return null;
            }
            $path = $targetDir . DIRECTORY_SEPARATOR . $filename;
            file_put_contents($path, $contents);
            return $path;
        } catch (\Throwable $e) {
            return null;
        }
    }

    private function skipRemoteCharts(): bool
    {
        if (app()->environment('testing')) {
            return true;
        }

        return (bool) config('services.quickchart.disabled', false);
    }
}