<?php

declare(strict_types=1);

namespace App\Services\Adsense;

use App\Models\AdsenseDailyStat;

final class AdsenseReportParser
{
    /**
     * @var array<string, string>
     */
    private const METRIC_COLUMNS = [
        'ESTIMATED_EARNINGS' => 'estimated_earnings',
        'PAGE_VIEWS' => 'page_views',
        'PAGE_VIEWS_CTR' => 'page_views_ctr',
        'PAGE_VIEWS_RPM' => 'page_views_rpm',
        'AD_REQUESTS' => 'ad_requests',
        'AD_REQUESTS_COVERAGE' => 'ad_requests_coverage',
        'AD_REQUESTS_CTR' => 'ad_requests_ctr',
        'AD_REQUESTS_RPM' => 'ad_requests_rpm',
        'MATCHED_AD_REQUESTS' => 'matched_ad_requests',
        'IMPRESSIONS' => 'impressions',
        'IMPRESSIONS_CTR' => 'impressions_ctr',
        'IMPRESSIONS_RPM' => 'impressions_rpm',
        'CLICKS' => 'clicks',
        'COST_PER_CLICK' => 'cost_per_click',
    ];

    /**
     * @var list<string>
     */
    private const INTEGER_COLUMNS = [
        'page_views',
        'ad_requests',
        'matched_ad_requests',
        'impressions',
        'clicks',
    ];

    /**
     * @param  array<string, mixed>  $report
     * @return list<array<string, mixed>>
     */
    public function parse(array $report, string $dimensionType, string $accountResourceName): array
    {
        $indexByName = $this->headerIndex($report['headers'] ?? []);
        $currencyCode = $this->currencyCode($report['headers'] ?? []);
        $rows = [];

        foreach ($report['rows'] ?? [] as $row) {
            if (! is_array($row)) {
                continue;
            }

            $cells = $row['cells'] ?? [];
            if (! is_array($cells)) {
                continue;
            }

            $date = $this->cell($cells, $indexByName, 'DATE');
            if (! is_string($date) || $date === '') {
                continue;
            }

            $dimensionKey = $this->dimensionKey($cells, $indexByName, $dimensionType);
            if ($dimensionKey === null || $dimensionKey === '') {
                continue;
            }

            $parsed = [
                'date' => $date,
                'account_resource_name' => $accountResourceName,
                'dimension_type' => $dimensionType,
                'dimension_key' => $dimensionKey,
                'dimension_label' => $this->dimensionLabel($cells, $indexByName, $dimensionType, $dimensionKey),
                'currency_code' => $currencyCode,
            ];

            foreach (self::METRIC_COLUMNS as $header => $column) {
                $parsed[$column] = $this->metricValue($cells, $indexByName, $header, $column);
            }

            $rows[] = $parsed;
        }

        return $rows;
    }

    public function currencyCode(array $headers): ?string
    {
        foreach ($headers as $header) {
            if (! is_array($header)) {
                continue;
            }

            $type = strtoupper((string) ($header['type'] ?? ''));
            $code = trim((string) ($header['currencyCode'] ?? ''));
            if ($type === 'METRIC_CURRENCY' && $code !== '') {
                return $code;
            }
        }

        return null;
    }

    /**
     * @return array<string, int>
     */
    private function headerIndex(mixed $headers): array
    {
        $index = [];
        if (! is_array($headers)) {
            return $index;
        }

        foreach ($headers as $position => $header) {
            if (! is_array($header)) {
                continue;
            }

            $name = strtoupper(trim((string) ($header['name'] ?? '')));
            if ($name === '') {
                continue;
            }

            $index[$name] = (int) $position;
        }

        return $index;
    }

    /**
     * @param  array<int, mixed>  $cells
     * @param  array<string, int>  $indexByName
     */
    private function dimensionKey(array $cells, array $indexByName, string $dimensionType): ?string
    {
        return match ($dimensionType) {
            AdsenseDailyStat::DIMENSION_TOTAL => AdsenseDailyStat::TOTAL_DIMENSION_KEY,
            AdsenseDailyStat::DIMENSION_AD_UNIT => $this->cell($cells, $indexByName, 'AD_UNIT_ID')
                ?? $this->cell($cells, $indexByName, 'AD_UNIT_NAME'),
            AdsenseDailyStat::DIMENSION_CUSTOM_CHANNEL => $this->cell($cells, $indexByName, 'CUSTOM_CHANNEL_ID')
                ?? $this->cell($cells, $indexByName, 'CUSTOM_CHANNEL_NAME'),
            AdsenseDailyStat::DIMENSION_PLATFORM => $this->cell($cells, $indexByName, 'PLATFORM_TYPE_CODE')
                ?? $this->cell($cells, $indexByName, 'PLATFORM_TYPE_NAME'),
            AdsenseDailyStat::DIMENSION_COUNTRY => $this->cell($cells, $indexByName, 'COUNTRY_CODE')
                ?? $this->cell($cells, $indexByName, 'COUNTRY_NAME'),
            default => null,
        };
    }

    /**
     * @param  array<int, mixed>  $cells
     * @param  array<string, int>  $indexByName
     */
    private function dimensionLabel(array $cells, array $indexByName, string $dimensionType, string $dimensionKey): string
    {
        $label = match ($dimensionType) {
            AdsenseDailyStat::DIMENSION_TOTAL => 'Total',
            AdsenseDailyStat::DIMENSION_AD_UNIT => $this->cell($cells, $indexByName, 'AD_UNIT_NAME'),
            AdsenseDailyStat::DIMENSION_CUSTOM_CHANNEL => $this->cell($cells, $indexByName, 'CUSTOM_CHANNEL_NAME'),
            AdsenseDailyStat::DIMENSION_PLATFORM => $this->cell($cells, $indexByName, 'PLATFORM_TYPE_NAME')
                ?? $this->cell($cells, $indexByName, 'PLATFORM_TYPE_CODE'),
            AdsenseDailyStat::DIMENSION_COUNTRY => $this->cell($cells, $indexByName, 'COUNTRY_NAME')
                ?? $this->cell($cells, $indexByName, 'COUNTRY_CODE'),
            default => $dimensionKey,
        };

        return is_string($label) && $label !== '' ? $label : $dimensionKey;
    }

    /**
     * @param  array<int, mixed>  $cells
     * @param  array<string, int>  $indexByName
     */
    private function cell(array $cells, array $indexByName, string $name): ?string
    {
        $name = strtoupper($name);
        if (! array_key_exists($name, $indexByName)) {
            return null;
        }

        $cell = $cells[$indexByName[$name]] ?? null;
        if (is_array($cell)) {
            $value = $cell['value'] ?? null;

            return is_scalar($value) ? (string) $value : null;
        }

        return is_scalar($cell) ? (string) $cell : null;
    }

    /**
     * @param  array<int, mixed>  $cells
     * @param  array<string, int>  $indexByName
     */
    private function metricValue(array $cells, array $indexByName, string $header, string $column): int|string|null
    {
        $raw = $this->cell($cells, $indexByName, $header);
        if ($raw === null || $raw === '') {
            return null;
        }

        if (in_array($column, self::INTEGER_COLUMNS, true)) {
            return (int) $raw;
        }

        if (! is_numeric($raw)) {
            return null;
        }

        return $raw;
    }
}