<?php

namespace Modules\EcommerceFinance\Services;

use Carbon\CarbonInterface;
use Illuminate\Support\Carbon;
use Modules\EcommerceFinance\Repositories\NonJingxiRefundMirrorRepository;
use Throwable;

class RefundPendingSyncStatus
{
    private const DATASETS = [
        NonJingxiRefundMirrorRepository::INFO_DATASET => '售后退款主表',
        NonJingxiRefundMirrorRepository::ITEM_DATASET => '售后商品明细',
        NonJingxiRefundMirrorRepository::SUPPLEMENT_DATASET => '淘系退款清单',
        NonJingxiRefundMirrorRepository::SUPPLEMENT_ITEM_DATASET => '淘系退款明细',
        NonJingxiRefundMirrorRepository::STATUS_DATASET => '聚水潭当前退款状态',
    ];

    public function __construct(
        private readonly NonJingxiRefundMirrorRepository $refunds,
    ) {}

    /**
     * @return array{
     *   state:string,
     *   title:string,
     *   message:string,
     *   last_succeeded_at:?string,
     *   last_attempted_at:?string,
     *   issues:list<array{dataset:string,label:string,message:string,error_code:?string}>
     * }
     */
    public function current(?CarbonInterface $at = null): array
    {
        $now = $at ? Carbon::instance($at) : now();
        $scheduledAt = $now->copy()->startOfDay()->setTime(6, 0);
        $deadline = $now->copy()->startOfDay()->setTime(10, 0);

        try {
            $states = $this->refunds->pendingConfirmationDailySyncStates();
        } catch (Throwable) {
            return [
                'state' => 'unavailable',
                'title' => '退款待确认同步状态不可用',
                'message' => '暂时无法读取同步状态，请检查共享镜像连接。',
                'last_succeeded_at' => null,
                'last_attempted_at' => null,
                'issues' => [[
                    'dataset' => '',
                    'label' => '退款待确认',
                    'message' => '同步状态读取失败',
                    'error_code' => 'status_unavailable',
                ]],
            ];
        }

        $issues = [];
        $running = false;
        $danger = false;
        $successTimes = [];
        $attemptTimes = [];

        foreach (self::DATASETS as $key => $label) {
            $state = $states[$key] ?? null;
            if (! is_array($state)) {
                $danger = true;
                $issues[] = $this->issue($key, $label, '尚未建立共享镜像', null);
                continue;
            }

            $status = (string) ($state['status'] ?? '');
            $errorCode = trim((string) ($state['last_error_code'] ?? '')) ?: null;
            $attemptedAt = $this->parseTime($state['last_attempted_at'] ?? null);
            $succeededAt = $this->parseTime($state['last_succeeded_at'] ?? null);

            if ($attemptedAt !== null) {
                $attemptTimes[] = $attemptedAt;
            }
            if ($succeededAt !== null) {
                $successTimes[] = $succeededAt;
            }

            if ($status === 'failed') {
                $danger = true;
                $issues[] = $this->issue($key, $label, '同步失败，已保留上次成功数据', $errorCode);
                continue;
            }

            if (empty($state['initial_completed_at'])) {
                $danger = true;
                $issues[] = $this->issue($key, $label, '首次同步尚未完成', $errorCode);
                continue;
            }

            if ($status === 'running') {
                $running = true;
                if ($now->greaterThanOrEqualTo($deadline)) {
                    $issues[] = $this->issue($key, $label, '今日 10:00 前同步尚未完成', $errorCode);
                }
                continue;
            }

            if ($now->greaterThanOrEqualTo($deadline)
                && (
                    $attemptedAt === null
                    || $attemptedAt->lessThan($scheduledAt)
                    || $succeededAt === null
                    || $succeededAt->greaterThan($deadline)
                )) {
                $issues[] = $this->issue($key, $label, '今日 10:00 前同步未完成', $errorCode);
            }
        }

        if ($issues !== []) {
            $state = $danger ? 'failed' : 'warning';

            return [
                'state' => $state,
                'title' => $danger ? '退款待确认同步异常' : '退款待确认同步未完成',
                'message' => $danger
                    ? '部分退款数据同步失败，页面仍显示最近一次成功数据。'
                    : '每日同步未在 10:00 前完成，请检查同步任务。',
                'last_succeeded_at' => $this->latest($successTimes),
                'last_attempted_at' => $this->latest($attemptTimes),
                'issues' => $issues,
            ];
        }

        return [
            'state' => $running ? 'syncing' : 'healthy',
            'title' => $running ? '退款待确认正在同步' : '退款待确认同步正常',
            'message' => $running
                ? '退款镜像正在同步，完成后会自动更新。'
                : '基础退款镜像每日 06:00 同步，当前退款状态每分钟刷新。',
            'last_succeeded_at' => $this->latest($successTimes),
            'last_attempted_at' => $this->latest($attemptTimes),
            'issues' => [],
        ];
    }

    /** @return array{dataset:string,label:string,message:string,error_code:?string} */
    private function issue(string $dataset, string $label, string $message, ?string $errorCode): array
    {
        return [
            'dataset' => $dataset,
            'label' => $label,
            'message' => $message,
            'error_code' => $errorCode,
        ];
    }

    private function parseTime(mixed $value): ?Carbon
    {
        $value = trim((string) $value);
        if ($value === '') {
            return null;
        }

        try {
            return Carbon::parse($value);
        } catch (Throwable) {
            return null;
        }
    }

    /** @param list<Carbon> $times */
    private function latest(array $times): ?string
    {
        if ($times === []) {
            return null;
        }

        usort($times, static fn (Carbon $left, Carbon $right): int => $right <=> $left);

        return $times[0]->toDateTimeString();
    }
}