<?php

namespace Modules\EcommerceFinance\Repositories;

use Illuminate\Database\ConnectionInterface;
use Illuminate\Database\Query\Builder;
use Illuminate\Support\Carbon;
use Illuminate\Support\Facades\Cache;
use Illuminate\Support\Facades\Schema;
use Modules\EcommerceFinance\Services\BusinessMirrorDatasetRegistry;
use RuntimeException;
use Throwable;

/** 快递应付运费对账的共享业务镜像只读访问。 */
class CourierFreightReconciliationMirrorRepository
{
    /** 保留旧契约，供现有结算同步和调用方识别。 */
    public const DATASET = 'jiansun.dbo.fys_express_courier_settlement';
    public const DETAILS_DATASET = 'jiansun.dbo.jst_order_express_details';
    public const EXTENSION_DATASET = 'jiansun.dbo.Jst_SendData_View_extension';
    public const OUTBOUND_DATASET = 'jiansun.dbo.jst_salesOutboundInfo';

    /** @var list<string> */
    private const REQUIRED_DATASETS = [
        self::DETAILS_DATASET,
        self::EXTENSION_DATASET,
        self::OUTBOUND_DATASET,
    ];

    /** 仅暴露附件中有演示值、且已经核对来源的字段。 */
    private const COLUMNS = [
        'detail_id', 'waybill', 'product_id', 'send_time', 'transaction_order_no',
        'province', 'city', 'district', 'barcode', 'express_name', 'express_name_2', 'quantity',
        'product_name', 'platform', 'shop_name', 'warehouse', 'volume', 'supplier',
        'length', 'width', 'height', 'freight', 'reconciliation_weight',
        'reconciliation_volume', 'month', 'status',
    ];

    private readonly ConnectionInterface $connection;

    public function __construct(
        private readonly BusinessMirrorDatasetRegistry $datasets,
        private readonly GenericBusinessMirrorRepository $mirror,
    ) {
        $this->connection = $mirror->connection();
    }

    public function available(): bool
    {
        try {
            $schema = Schema::connection($this->connection->getName());
            if (! $schema->hasTable('business_mirror_table_states')) {
                return false;
            }

            foreach (self::REQUIRED_DATASETS as $key) {
                if (! $schema->hasTable($this->datasets->get($key)->targetTable())) {
                    return false;
                }
            }

            return true;
        } catch (Throwable) {
            return false;
        }
    }

    public function ready(): bool
    {
        try {
            foreach (self::REQUIRED_DATASETS as $key) {
                if (! $this->mirror->ready($this->datasets->get($key))) {
                    return false;
                }
            }

            return true;
        } catch (Throwable) {
            return false;
        }
    }

    /** @return array<string,mixed>|null */
    public function state(): ?array
    {
        try {
            $states = [];
            foreach (self::REQUIRED_DATASETS as $key) {
                $state = $this->mirror->state($this->datasets->get($key));
                if (is_array($state)) {
                    $states[$key] = $state;
                }
            }
            if ($states === []) {
                return null;
            }

            $first = $states[self::DETAILS_DATASET] ?? reset($states);
            $initial = array_values(array_filter(array_map(
                static fn (array $state): ?string => $state['initial_completed_at'] ?? null,
                $states,
            )));
            $succeeded = array_values(array_filter(array_map(
                static fn (array $state): ?string => $state['last_succeeded_at'] ?? null,
                $states,
            )));
            $statuses = array_map(static fn (array $state): string => (string) ($state['status'] ?? 'pending'), $states);

            $first['initial_completed_at'] = count($initial) === count(self::REQUIRED_DATASETS) ? min($initial) : null;
            $first['last_succeeded_at'] = count($succeeded) === count(self::REQUIRED_DATASETS) ? min($succeeded) : null;
            $first['status'] = in_array('failed', $statuses, true)
                ? 'failed'
                : (in_array('running', $statuses, true) ? 'running' : (count(array_filter($statuses, static fn (string $value): bool => $value === 'succeeded')) === count(self::REQUIRED_DATASETS) ? 'succeeded' : 'pending'));
            $first['datasets'] = $states;

            return $first;
        } catch (Throwable) {
            return null;
        }
    }

    /** @return array{code:string,last_succeeded_at:?string,lag_minutes:?int} */
    public function syncStatus(?array $state = null): array
    {
        $state ??= $this->state();
        if (! is_array($state)) {
            return ['code' => 'unavailable', 'last_succeeded_at' => null, 'lag_minutes' => null];
        }

        $lastSucceeded = $state['last_succeeded_at'] ?? null;
        $lagMinutes = null;
        if (is_string($lastSucceeded) && $lastSucceeded !== '') {
            try {
                $lagMinutes = (int) ceil(max(0, now()->getTimestamp() - Carbon::parse($lastSucceeded)->getTimestamp()) / 60);
            } catch (Throwable) {
                $lagMinutes = null;
            }
        }

        $status = (string) ($state['status'] ?? 'pending');
        if (($state['initial_completed_at'] ?? null) === null) {
            $code = $status === 'failed' ? 'initial_failed' : ($status === 'running' ? 'initializing' : 'pending');
        } elseif ($status === 'failed') {
            $code = 'failed';
        } elseif ($status === 'running') {
            $code = 'syncing';
        } elseif ($lagMinutes === null || $lagMinutes > max((int) config('upstream_mirrors.courier_information.stale_after_minutes', 60), 1)) {
            $code = 'stale';
        } else {
            $code = 'fresh';
        }

        return ['code' => $code, 'last_succeeded_at' => $lastSucceeded, 'lag_minutes' => $lagMinutes];
    }

    /**
     * @param array<string,string> $filters
     * @return array{data:list<array<string,mixed>>,total:?int,has_more:bool,summary:?array,state:array<string,mixed>|null,sync:array<string,mixed>}
     */
    public function paginate(array $filters, int $page, int $perPage): array
    {
        if (! $this->ready()) {
            throw new RuntimeException('courier_freight_reconciliation_mirror_not_ready');
        }

        $page = max($page, 1);
        $perPage = min(max($perPage, 1), 100);
        $summary = Cache::get($this->summaryCacheKey($filters));
        // Select page identifiers before loading the wide optional details. A
        // contains-waybill filter can then scan the compact covering index.
        $candidates = $this->filteredQuery($filters, trim((string) ($filters['express_name'] ?? '')) !== '')
            ->select('d.id')
            ->orderByDesc('d.id')
            ->offset(($page - 1) * $perPage)->limit($perPage + 1);
        $rows = $this->detailQuery($candidates)->select($this->selectColumns())
            ->orderByDesc('d.id')
            ->get()
            ->map(fn (object $row): array => $this->mapRow($row))
            ->all();
        $state = $this->state();

        return [
            'data' => array_slice($rows, 0, $perPage),
            'total' => $summary['count'] ?? null,
            'has_more' => count($rows) > $perPage,
            'summary' => $summary,
            'state' => $state,
            'sync' => $this->syncStatus($state),
        ];
    }

    /** Send a small pending response before starting the bounded calculation. */
    public function requestSummary(array $filters): ?array
    {
        $key = $this->summaryCacheKey($filters);
        if (is_array($cached = Cache::get($key))) return $cached;
        if (Cache::has($key . ':failed')) throw new RuntimeException('courier_summary_recently_failed');
        app()->terminating(function () use ($filters, $key): void {
            try {
                $this->summarize($filters);
            } catch (Throwable $exception) {
                Cache::put($key . ':failed', true, 60);
                report($exception);
            }
        });
        return null;
    }

    /** The separate summary request preserves full-filter totals without delaying rows. */
    public function summarize(array $filters): ?array
    {
        if (! $this->ready()) throw new RuntimeException('courier_freight_reconciliation_mirror_not_ready');
        $key = $this->summaryCacheKey($filters);
        if (is_array($cached = Cache::get($key))) return $cached;
        // One expensive aggregate at a time, including requests for different filters.
        $lock = Cache::lock('courier-freight-summary:calculation', 360);
        if (! $lock->get()) return null;
        $previousSettings = [];
        try {
            if (is_array($cached = Cache::get($key))) return $cached;
            $unfiltered = array_filter($filters, static fn ($value): bool => trim((string) $value) !== '') === [];
            if ($this->connection->getDriverName() === 'mysql') {
                $settings = ['max_statement_time' => 300];
                if ($unfiltered) {
                    $settings += [
                        'optimizer_switch' => 'derived_merge=off,derived_with_keys=off',
                        'join_cache_level' => 8,
                        // 全量汇总要把 300 万行左右的明细和 400 万行的最新关联表做哈希
                        // 关联；16MB 的哈希表装不下会退化成磁盘多趟扫描（实测超过
                        // max_statement_time 也跑不完）。128MB 缓冲约 110 秒出结果。
                        'join_buffer_size' => 134217728,
                        'join_buffer_space_limit' => 402653184,
                    ];
                }
                foreach ($settings as $name => $value) {
                    $previousSettings[$name] = $this->connection->selectOne('SELECT @@SESSION.' . $name . ' AS value')->value;
                    $this->setSummarySessionSetting($name, $value);
                }
            }
            $asOf = now()->toDateTimeString();
            $row = $this->summaryQuery($filters)->selectRaw(
                'COUNT(d.id) AS aggregate_count, COALESCE(SUM(o.freight), 0) AS freight',
            )->first();
            $summary = ['count' => (int) $row->aggregate_count, 'freight' => (float) $row->freight, 'computed_at' => $asOf];
            // 全量（无筛选）汇总要跑两分钟左右，缓存久一点，避免频繁重算；
            // 带筛选的汇总走索引，很快，保持原来的 15 分钟。
            Cache::put($key, $summary, $unfiltered ? 3600 : 900);
            return $summary;
        } finally {
            try {
                foreach (array_reverse($previousSettings, true) as $name => $value) {
                    $this->setSummarySessionSetting($name, $value);
                }
            } finally {
                $lock->release();
            }
        }
    }

    private function setSummarySessionSetting(string $name, mixed $value): void
    {
        if ($name === 'optimizer_switch') {
            $this->connection->statement('SET SESSION optimizer_switch=?', [$value]);
            return;
        }
        // MariaDB rejects quoted numeric values for these session variables.
        // Names come only from the fixed settings map above.
        $this->connection->statement('SET SESSION ' . $name . '=' . (float) $value);
    }

    private function summaryCacheKey(array $filters): string
    {
        $filters = array_filter(array_map(static fn ($value): string => trim((string) $value), $filters), static fn (string $value): bool => $value !== '');
        ksort($filters);
        return 'courier-freight-summary:v3:' . hash('sha256', json_encode($filters));
    }

    /** Materialize latest associations once; use compact collation-aware hash joins for the full scan. */
    private function summaryQuery(array $filters = []): Builder
    {
        $activeFilters = array_filter($filters, static fn ($value): bool => trim((string) $value) !== '');
        if ($activeFilters !== []) {
            $ids = $this->filteredQuery($filters, ($filters['express_name'] ?? '') !== '')->select('d.id')->distinct();
            return $this->detailQuery($ids);
        }
        $columns = ['so_id', 'io_id'];
        $lookup = fn (string $column): string => $this->connection->getDriverName() === 'mysql'
            ? 'CRC32(WEIGHT_STRING(RTRIM(' . $column . ')))'
            : 'SUBSTR(' . $column . ', 1, 64)';
        $extension = $this->latestSummaryProjection(self::EXTENSION_DATASET, 'so_id', $columns)
            ->selectRaw($lookup('candidate.so_id') . ' AS lookup_key');
        $outbound = $this->latestSummaryProjection(self::OUTBOUND_DATASET, 'io_id', ['io_id', 'freight']);
        $query = $this->connection->table($this->datasets->get(self::DETAILS_DATASET)->targetTable() . ' as d')
            ->leftJoinSub($extension, 'x', static function ($join) use ($lookup): void {
                $join->whereRaw('x.lookup_key = ' . $lookup('d.so_id'))
                    // Keep the full comparison: a hash collision must never
                    // combine different orders or multiply freight amounts.
                    ->whereRaw("COALESCE(x.so_id, '') = COALESCE(d.so_id, '')");
            })
            ->leftJoinSub($outbound, 'o', 'o.io_id', '=', 'x.io_id');
        return $this->filteredQuery([], true, $query);
    }

    private function latestSummaryProjection(string $dataset, string $relation, array $columns): Builder
    {
        $table = $this->datasets->get($dataset)->targetTable();
        $ids = $this->connection->table($table)->select($relation)->selectRaw('MAX(Id) AS latest_id')->groupBy($relation)->orderByRaw('NULL');
        return $this->connection->query()->fromSub($ids, 'latest_ids')
            ->join($table . ' as candidate', static function ($join) use ($relation): void {
                $join->on('latest_ids.' . $relation, '=', 'candidate.' . $relation)->on('latest_ids.latest_id', '=', 'candidate.Id');
            })->select(array_map(static fn (string $column): string => 'candidate.' . $column, $columns));
    }

    private function filteredQuery(array $filters, bool $includeRelations = true, ?Builder $base = null): Builder
    {
        $query = ($base ?? ($includeRelations ? $this->detailQuery() : $this->connection->table($this->datasets->get(self::DETAILS_DATASET)->targetTable() . ' as d')))
            ->whereNotNull('d.logistic_id')->where('d.logistic_id', '!=', '');
        $this->containsFilter($query, 'd.logistic_id', $filters['express_no'] ?? '');

        if (($filters['express_name'] ?? '') !== '') {
            $needle = $this->contains((string) $filters['express_name']);
            $query->where(function (Builder $name) use ($needle): void {
                $name->whereRaw("d.logistic_company_name LIKE ? ESCAPE '!'", [$needle])
                    ->orWhereRaw("x.expressName LIKE ? ESCAPE '!'", [$needle]);
            });
        }
        if (($filters['month'] ?? '') !== '' && preg_match('/^\d{4}-\d{2}$/', (string) $filters['month']) === 1) {
            $from = (string) $filters['month'] . '-01';
            $query->where('d.send_time', '>=', $from . ' 00:00:00')
                ->where('d.send_time', '<', date('Y-m-d 00:00:00', strtotime($from . ' +1 month')));
        }
        if (($filters['status'] ?? '') !== '') {
            $query->where('d.logistic_status_name', '=', $filters['status']);
        }
        if (($filters['modified_from'] ?? '') !== '') {
            $query->where('d.updatedAt', '>=', $filters['modified_from'] . ' 00:00:00');
        }
        if (($filters['modified_to'] ?? '') !== '') {
            $query->where('d.updatedAt', '<', date('Y-m-d 00:00:00', strtotime($filters['modified_to'] . ' +1 day')));
        }

        return $query;
    }

    private function detailQuery(?Builder $pageIds = null): Builder
    {
        $details = $this->datasets->get(self::DETAILS_DATASET)->targetTable();
        $extension = $this->datasets->get(self::EXTENSION_DATASET)->targetTable();
        $outbound = $this->datasets->get(self::OUTBOUND_DATASET)->targetTable();

        $query = $pageIds === null ? $this->connection->table($details . ' as d')
            : $this->connection->query()->fromSub($pageIds, 'page_ids')->join($details . ' as d', 'd.id', '=', 'page_ids.id');
        return $query
            ->leftJoinSub($this->latestBy($extension, 'so_id', 'Id'), 'x', 'x.so_id', '=', 'd.so_id')
            ->leftJoinSub($this->latestBy($outbound, 'io_id', 'Id'), 'o', 'o.io_id', '=', 'x.io_id');
    }

    /** 固定取关联键下 Id 最大的一行，避免一对多重复页面行和运费汇总。 */
    private function latestBy(string $table, string $relationColumn, string $idColumn): Builder
    {
        return $this->connection->table($table . ' as candidate')
            ->whereNotExists(function (Builder $query) use ($table, $relationColumn, $idColumn): void {
                $query->selectRaw('1')
                    ->from($table . ' as newer')
                    ->whereColumn('newer.' . $relationColumn, '=', 'candidate.' . $relationColumn)
                    ->whereColumn('newer.' . $idColumn, '>', 'candidate.' . $idColumn);
            });
    }

    /** @return list<string> */
    private function selectColumns(): array
    {
        return [
            'd.id as detail_id', 'd.logistic_id as waybill', 'x.shop_i_id as product_id',
            'd.send_time', $this->connection->raw('COALESCE(x.so_id, d.so_id) as transaction_order_no'), 'x.receiver_state as province',
            'x.receiver_city as city', 'x.receiver_district as district',
            'x.sku_ids as barcode',
            'd.logistic_company_name as express_name', 'x.expressName as express_name_2',
            'x.qty as quantity', 'x.sku_name as product_name', 'd.platform_name as platform',
            $this->connection->raw('COALESCE(x.shop_name, d.shop_name) as shop_name'),
            $this->connection->raw('COALESCE(x.wareHoursName, d.warehouse_name) as warehouse'), 'x.volume as volume',
            'x.supplier_name as supplier', 'x.l as length', 'x.w as width', 'x.h as height',
            'o.freight as freight', 'd.f_weight as reconciliation_weight',
            'x.volume as reconciliation_volume', 'd.logistic_status_name as status',
        ];
    }

    /** @return array<string,mixed> */
    private function mapRow(object $row): array
    {
        $mapped = [];
        foreach (self::COLUMNS as $column) {
            $mapped[$column] = $row->{$column} ?? null;
        }

        $sendTime = $mapped['send_time'];
        $mapped['month'] = is_string($sendTime) ? substr($sendTime, 0, 7) : null;
        foreach (['length', 'width', 'height', 'volume', 'freight', 'reconciliation_weight', 'reconciliation_volume'] as $number) {
            $mapped[$number] = $mapped[$number] === null || $mapped[$number] === '' ? null : (float) $mapped[$number];
        }
        if ($mapped['quantity'] !== null && $mapped['quantity'] !== '') {
            $mapped['quantity'] = (int) $mapped['quantity'];
        }

        return $mapped;
    }

    private function containsFilter(Builder $query, string $column, mixed $value): void
    {
        $value = trim((string) $value);
        if ($value !== '') {
            $query->whereRaw($column . " LIKE ? ESCAPE '!'", [$this->contains($value)]);
        }
    }

    private function contains(string $value): string
    {
        return '%' . str_replace(['!', '%', '_'], ['!!', '!%', '!_'], $value) . '%';
    }
}