<?php

namespace App\Support;

/**
 * 赛道打分表：结构校验、分项打分与总分汇总。
 *
 * 约定：
 * - 配置时 Σ max_score 必须 = 100
 * - 提交时须给每一项打分：0 ≤ 得分 ≤ 该项 max_score，最多两位小数
 * - 项目总分 = 各项得分之和（服务端计算，不采信客户端填写的 line_total）
 * - 0 ≤ 总分 ≤ 100，最多两位小数
 */
class TrackScoringSheet
{
    public const FULL_SCORE = 100.0;

    public const SCORE_DECIMALS = 2;

    /**
     * @param  mixed  $raw
     * @return array{ok: true, sheet: array{version: int, title: string, full_score: float, items: list<array{key: string, sort: int, category: string, title: string, criteria: string, max_score: float}>}}|array{ok: false, message: string}
     */
    public static function parseAndValidateConfig(mixed $raw): array
    {
        if ($raw === null) {
            return ['ok' => false, 'message' => '打分表不能为空'];
        }

        if (is_string($raw)) {
            $trimmed = trim($raw);
            if ($trimmed === '') {
                return ['ok' => false, 'message' => '打分表不能为空'];
            }
            try {
                $raw = json_decode($trimmed, true, 512, JSON_THROW_ON_ERROR);
            } catch (\JsonException) {
                return ['ok' => false, 'message' => '打分表 JSON 格式不正确'];
            }
        }

        if (! is_array($raw)) {
            return ['ok' => false, 'message' => '打分表须为 JSON 对象'];
        }

        $title = isset($raw['title']) && is_string($raw['title']) ? trim($raw['title']) : '';
        $itemsRaw = $raw['items'] ?? null;
        if (! is_array($itemsRaw) || count($itemsRaw) === 0) {
            return ['ok' => false, 'message' => '打分表至少包含一项指标'];
        }

        $items = [];
        $keys = [];
        $sumMax = 0.0;

        foreach ($itemsRaw as $idx => $row) {
            if (! is_array($row)) {
                return ['ok' => false, 'message' => '第 '.((int) $idx + 1).' 项指标格式无效'];
            }

            $key = isset($row['key']) && is_string($row['key']) ? trim($row['key']) : '';
            if ($key === '' || ! preg_match('/^[a-zA-Z][a-zA-Z0-9_]{0,63}$/', $key)) {
                return ['ok' => false, 'message' => '第 '.((int) $idx + 1).' 项指标 key 无效（字母开头，字母数字下划线）'];
            }
            if (isset($keys[$key])) {
                return ['ok' => false, 'message' => '指标 key 重复：'.$key];
            }
            $keys[$key] = true;

            $category = isset($row['category']) && is_string($row['category']) ? trim($row['category']) : '';
            $itemTitle = isset($row['title']) && is_string($row['title']) ? trim($row['title']) : '';
            $criteria = isset($row['criteria']) && is_string($row['criteria']) ? trim($row['criteria']) : '';
            if ($category === '' || $itemTitle === '') {
                return ['ok' => false, 'message' => '第 '.((int) $idx + 1).' 项须填写指标分类与评审指标'];
            }

            if (! isset($row['max_score']) || ! is_numeric($row['max_score'])) {
                return ['ok' => false, 'message' => '「'.$itemTitle.'」分值无效'];
            }
            $max = (float) $row['max_score'];
            if ($max <= 0 || $max > self::FULL_SCORE) {
                return ['ok' => false, 'message' => '「'.$itemTitle.'」分值须在 0～100 之间且大于 0'];
            }

            $sort = isset($row['sort']) && is_numeric($row['sort']) ? (int) $row['sort'] : ((int) $idx + 1);

            $items[] = [
                'key' => $key,
                'sort' => $sort,
                'category' => $category,
                'title' => $itemTitle,
                'criteria' => $criteria,
                'max_score' => $max,
            ];
            $sumMax += $max;
        }

        usort($items, fn (array $a, array $b) => $a['sort'] <=> $b['sort'] ?: strcmp($a['key'], $b['key']));

        if (abs($sumMax - self::FULL_SCORE) > 0.0001) {
            return [
                'ok' => false,
                'message' => '各项分值之和须为 '.self::FULL_SCORE.' 分，当前为 '.rtrim(rtrim(number_format($sumMax, 4, '.', ''), '0'), '.'),
            ];
        }

        $version = isset($raw['version']) && is_numeric($raw['version']) ? (int) $raw['version'] : 1;

        return [
            'ok' => true,
            'sheet' => [
                'version' => max(1, $version),
                'title' => $title,
                'full_score' => self::FULL_SCORE,
                'items' => $items,
            ],
        ];
    }

    /**
     * @param  array<string, mixed>|null  $sheet
     */
    public static function isConfigured(?array $sheet): bool
    {
        if ($sheet === null) {
            return false;
        }
        $parsed = self::parseAndValidateConfig($sheet);

        return $parsed['ok'] === true;
    }

    /**
     * @param  array{version: int, title: string, full_score: float, items: list<array{key: string, sort: int, category: string, title: string, criteria: string, max_score: float}>}  $sheet
     * @param  array<string, mixed>  $payload  期望 { scores: { [itemKey]: number } }
     * @return array{ok: true, scores: array<string, float>, line_total: float, payload: array<string, mixed>}|array{ok: false, message: string}
     */
    public static function normalizeSubmitPayload(array $sheet, array $payload): array
    {
        $rawScores = $payload['scores'] ?? null;
        if (! is_array($rawScores)) {
            return ['ok' => false, 'message' => '请为每一项填写有效得分'];
        }

        $scores = [];
        $sum = 0.0;

        foreach ($sheet['items'] as $item) {
            $key = $item['key'];
            $title = $item['title'];
            $max = (float) $item['max_score'];
            if (! array_key_exists($key, $rawScores) || $rawScores[$key] === null || $rawScores[$key] === '') {
                return ['ok' => false, 'message' => '请为每一项填写有效得分'];
            }

            $raw = $rawScores[$key];
            if (is_bool($raw) || is_array($raw) || ! is_numeric($raw)) {
                return ['ok' => false, 'message' => '「'.$title.'」得分须为数字'];
            }
            if (preg_match('/\.\d{3,}/', (string) $raw) === 1) {
                return ['ok' => false, 'message' => '「'.$title.'」得分最多保留两位小数'];
            }

            $n = (float) $raw;
            if ($n < 0) {
                return ['ok' => false, 'message' => '「'.$title.'」得分不能小于 0'];
            }
            if ($n - $max > 0.0000001) {
                $maxLabel = rtrim(rtrim(number_format($max, self::SCORE_DECIMALS, '.', ''), '0'), '.');

                return ['ok' => false, 'message' => '「'.$title.'」得分不能高于该项分值 '.$maxLabel];
            }

            $scores[$key] = $n;
            $sum += $n;
        }

        $lineTotal = round($sum, self::SCORE_DECIMALS);
        if ($lineTotal < 0) {
            return ['ok' => false, 'message' => '项目总分不能小于 0'];
        }
        if ($lineTotal > self::FULL_SCORE) {
            return ['ok' => false, 'message' => '项目总分不能大于 100'];
        }

        $outPayload = [
            'line_total' => $lineTotal,
            'scores' => $scores,
            'sheet_snapshot' => [
                'version' => $sheet['version'],
                'title' => $sheet['title'],
                'full_score' => $sheet['full_score'],
                'items' => array_map(static fn (array $it) => [
                    'key' => $it['key'],
                    'sort' => $it['sort'],
                    'category' => $it['category'],
                    'title' => $it['title'],
                    'max_score' => $it['max_score'],
                ], $sheet['items']),
            ],
        ];

        if (isset($payload['comment']) && is_string($payload['comment'])) {
            $outPayload['comment'] = trim($payload['comment']);
        }

        return [
            'ok' => true,
            'scores' => $scores,
            'line_total' => $lineTotal,
            'payload' => $outPayload,
        ];
    }
}