<?php

namespace App\Services\AgentSettlement;

use App\Models\AdminUser;
use App\Support\AdminDataScope;
use App\Support\AdminAgentSettlementScope;
use App\Support\CurrencyFormatter;
use App\Support\PlayerFundingMode;
use Carbon\Carbon;
use Illuminate\Support\Facades\DB;

/** 结算中心统一账务流水（credit_ledger + 收付 + 调账）。 */
final class SettlementCenterLedgerService
{
    /**
     * @return array{
     *   items: list<array<string, mixed>>,
     *   total: int,
     *   page: int,
     *   per_page: int,
     *   ledger_source: string,
     * }
     */
    public function listUnified(
        AdminUser $admin,
        string $siteCode,
        int $page,
        int $perPage,
        SettlementLedgerListFilters $filters = new SettlementLedgerListFilters,
    ): array {
        $periodId = $filters->settlementPeriodId;
        $range = $this->resolveCreatedRange($periodId, $filters->createdFrom, $filters->createdTo);
        $playerBills = $this->playerBillsMap($admin, $siteCode, $periodId);

        $items = [];
        $includeCredit = $this->includeEntryKind($filters, 'credit');
        $includePayment = $this->includeEntryKind($filters, 'payment');
        $includeAdjustment = $this->includeEntryKind($filters, 'adjustment');

        if ($includeCredit) {
            $creditRows = $this->fetchCreditRows($admin, $siteCode, $range, $filters->playerId);
            foreach ($creditRows as $row) {
                $pid = (int) $row->player_id;
                $bill = $playerBills[$pid] ?? null;
                $items[] = $this->formatCreditEntry($row, $bill);
            }
        }
        if ($includePayment) {
            foreach ($this->fetchPaymentRows($admin, $siteCode, $periodId, $filters->playerId) as $row) {
                $items[] = $this->formatPaymentEntry($row);
            }
        }
        if ($includeAdjustment) {
            foreach ($this->fetchAdjustmentRows($admin, $siteCode, $periodId, $filters->playerId) as $row) {
                if ($filters->badDebtOnly && (string) $row->adjustment_type !== 'bad_debt') {
                    continue;
                }
                $items[] = $this->formatAdjustmentEntry($row);
            }
        }

        $items = $this->applyFilters($items, $filters);

        usort($items, static function (array $a, array $b): int {
            return strcmp((string) ($b['created_at'] ?? ''), (string) ($a['created_at'] ?? ''));
        });

        $total = count($items);
        $offset = max(0, ($page - 1) * $perPage);
        $pageItems = array_slice($items, $offset, $perPage);

        return [
            'items' => array_values($pageItems),
            'total' => $total,
            'page' => $page,
            'per_page' => $perPage,
            'ledger_source' => 'settlement_ledger',
        ];
    }

    /**
     * @return array{0: Carbon|null, 1: Carbon|null}
     */
    private function includeEntryKind(SettlementLedgerListFilters $filters, string $kind): bool
    {
        if ($filters->badDebtOnly) {
            return $kind === 'adjustment';
        }

        $selected = $filters->entryKind;
        if ($selected === null || $selected === '' || $selected === 'all') {
            return true;
        }

        return $selected === $kind;
    }

    /**
     * @param  list<array<string, mixed>>  $items
     * @return list<array<string, mixed>>
     */
    private function applyFilters(array $items, SettlementLedgerListFilters $filters): array
    {
        return array_values(array_filter($items, function (array $row) use ($filters): bool {
            if ($filters->badDebtOnly) {
                if (($row['entry_kind'] ?? '') !== 'adjustment' || ($row['biz_type'] ?? '') !== 'bad_debt') {
                    return false;
                }
            } elseif ($filters->entryKind === 'adjustment') {
                if (($row['entry_kind'] ?? '') === 'adjustment' && ($row['biz_type'] ?? '') === 'bad_debt') {
                    return false;
                }
            }

            if ($filters->txnNo !== null) {
                $needle = strtolower($filters->txnNo);
                $hay = strtolower((string) ($row['txn_no'] ?? ''));
                if (! str_contains($hay, $needle)) {
                    return false;
                }
            }

            if ($filters->playerAccount !== null) {
                $needle = strtolower($filters->playerAccount);
                $haystack = strtolower(implode(' ', array_filter([
                    (string) ($row['username'] ?? ''),
                    (string) ($row['nickname'] ?? ''),
                    (string) ($row['site_player_id'] ?? ''),
                ])));
                if (! str_contains($haystack, $needle)) {
                    return false;
                }
            }

            if ($filters->bizType !== null && ($row['biz_type'] ?? '') !== $filters->bizType) {
                return false;
            }

            if ($filters->billStatus !== null && ($row['bill_status'] ?? '') !== $filters->billStatus) {
                return false;
            }

            if ($filters->actionableOnly) {
                $actions = $row['available_actions'] ?? [];
                $operational = array_filter(
                    $actions,
                    static fn (string $a): bool => ! in_array($a, ['view_player', 'view_bill'], true),
                );
                if ($operational === []) {
                    return false;
                }
            }

            return true;
        }));
    }

    private function resolveCreatedRange(
        ?int $settlementPeriodId,
        ?string $createdFrom,
        ?string $createdTo,
    ): ?array {
        if ($settlementPeriodId !== null && $settlementPeriodId > 0) {
            $period = DB::table('settlement_periods')->where('id', $settlementPeriodId)->first();
            if ($period === null) {
                return null;
            }

            return [
                Carbon::parse($period->period_start)->startOfDay(),
                Carbon::parse($period->period_end)->endOfDay(),
            ];
        }

        $from = $createdFrom !== null && $createdFrom !== ''
            ? Carbon::parse($createdFrom)->startOfDay()
            : null;
        $to = $createdTo !== null && $createdTo !== ''
            ? Carbon::parse($createdTo)->endOfDay()
            : null;

        if ($from === null && $to === null) {
            return null;
        }

        return [
            $from ?? Carbon::parse('1970-01-01')->startOfDay(),
            $to ?? Carbon::now()->endOfDay(),
        ];
    }

    /**
     * @return array<int, object>
     */
    private function playerBillsMap(AdminUser $admin, string $siteCode, ?int $periodId): array
    {
        $query = DB::table('settlement_bills as sb')
            ->join('settlement_periods as sp', 'sp.id', '=', 'sb.settlement_period_id')
            ->join('players as p', function ($join): void {
                $join->on('p.id', '=', 'sb.owner_id')->where('sb.owner_type', '=', 'player');
            })
            ->where('p.site_code', $siteCode)
            ->where('sb.bill_type', 'player')
            ->select([
                'sb.id',
                'sb.owner_id as player_id',
                'sb.status',
                'sb.bill_type',
                'sb.net_amount',
                'sb.unpaid_amount',
                'sb.paid_amount',
                'sb.settlement_period_id',
            ])
            ->orderByDesc('sb.id');

        if ($periodId !== null && $periodId > 0) {
            abort_if(! AdminAgentSettlementScope::periodAccessible($admin, $periodId), 403);
            $query->where('sb.settlement_period_id', $periodId);
        }

        AdminDataScope::applyToPlayersAlias($query, $admin, 'p');

        $map = [];
        foreach ($query->limit(500)->get() as $bill) {
            $pid = (int) $bill->player_id;
            if (! isset($map[$pid])) {
                $map[$pid] = $bill;

                continue;
            }
            $existing = $map[$pid];
            if ((string) $bill->status === 'pending_confirm') {
                $map[$pid] = $bill;
            } elseif ((string) $existing->status !== 'pending_confirm'
                && (int) $bill->unpaid_amount > 0
                && (int) $existing->unpaid_amount <= 0) {
                $map[$pid] = $bill;
            }
        }

        return $map;
    }

    /**
     * @param  array{0: Carbon, 1: Carbon}|null  $range
     * @return list<object>
     */
    private function fetchCreditRows(
        AdminUser $admin,
        string $siteCode,
        ?array $range,
        ?int $playerId,
    ): array {
        $query = DB::table('credit_ledger as cl')
            ->join('players as p', function ($join): void {
                $join->on('p.id', '=', 'cl.owner_id')
                    ->where('cl.owner_type', '=', 'player');
            })
            ->where('p.site_code', $siteCode)
            ->where('p.funding_mode', PlayerFundingMode::CREDIT)
            ->select([
                'cl.id',
                'cl.amount',
                'cl.reason',
                'cl.ref_type',
                'cl.ref_id',
                'cl.created_at',
                'p.id as player_id',
                'p.site_code',
                'p.site_player_id',
                'p.username',
                'p.nickname',
                'p.funding_mode',
                'p.auth_source',
                'p.default_currency',
            ])
            ->orderByDesc('cl.id');

        AdminDataScope::applyToPlayersAlias($query, $admin, 'p');

        if ($playerId !== null && $playerId > 0) {
            $query->where('p.id', $playerId);
        }

        if ($range !== null) {
            $query->whereBetween('cl.created_at', $range);
        }

        return $query->limit(500)->get()->all();
    }

    /**
     * @return list<object>
     */
    private function fetchPaymentRows(
        AdminUser $admin,
        string $siteCode,
        ?int $periodId,
        ?int $playerId,
    ): array {
        $query = DB::table('payment_records as pr')
            ->join('settlement_bills as sb', 'sb.id', '=', 'pr.settlement_bill_id')
            ->join('settlement_periods as sp', 'sp.id', '=', 'sb.settlement_period_id')
            ->join('players as p', function ($join): void {
                $join->on('p.id', '=', 'sb.owner_id')
                    ->where('sb.owner_type', '=', 'player');
            })
            ->where('p.site_code', $siteCode)
            ->select([
                'pr.id',
                'pr.amount',
                'pr.method',
                'pr.status',
                'pr.created_at',
                'pr.settlement_bill_id',
                'sb.status as bill_status',
                'sb.bill_type',
                'sb.unpaid_amount',
                'p.id as player_id',
                'p.site_player_id',
                'p.username',
                'p.nickname',
                'p.auth_source',
                'p.funding_mode',
                'p.default_currency',
            ])
            ->orderByDesc('pr.id');

        if ($periodId !== null && $periodId > 0) {
            $query->where('sb.settlement_period_id', $periodId);
        }

        if ($playerId !== null && $playerId > 0) {
            $query->where('p.id', $playerId);
        }

        AdminDataScope::applyToPlayersAlias($query, $admin, 'p');

        $siteIds = $admin->accessibleAdminSiteIds();
        if ($siteIds !== null) {
            if ($siteIds === []) {
                return [];
            }
            $query->whereIn('sp.admin_site_id', $siteIds);
        }

        return $query->limit(300)->get()->all();
    }

    /**
     * @return list<object>
     */
    private function fetchAdjustmentRows(
        AdminUser $admin,
        string $siteCode,
        ?int $periodId,
        ?int $playerId,
    ): array {
        $query = DB::table('settlement_adjustments as sa')
            ->leftJoin('settlement_bills as sb', 'sb.id', '=', 'sa.original_bill_id')
            ->leftJoin('settlement_periods as sp', 'sp.id', '=', 'sa.settlement_period_id')
            ->leftJoin('players as p', function ($join): void {
                $join->on('p.id', '=', 'sb.owner_id')
                    ->where('sb.owner_type', '=', 'player');
            })
            ->where('p.site_code', $siteCode)
            ->select([
                'sa.id',
                'sa.amount',
                'sa.adjustment_type',
                'sa.reason',
                'sa.created_at',
                'sa.original_bill_id as settlement_bill_id',
                'sb.status as bill_status',
                'sb.bill_type',
                'sb.unpaid_amount',
                'p.id as player_id',
                'p.site_player_id',
                'p.username',
                'p.nickname',
                'p.auth_source',
                'p.funding_mode',
                'p.default_currency',
            ])
            ->orderByDesc('sa.id');

        if ($periodId !== null && $periodId > 0) {
            $query->where('sa.settlement_period_id', $periodId);
        }

        if ($playerId !== null && $playerId > 0) {
            $query->where('p.id', $playerId);
        }

        AdminDataScope::applyToPlayersAlias($query, $admin, 'p');

        $siteIds = $admin->accessibleAdminSiteIds();
        if ($siteIds !== null) {
            if ($siteIds === []) {
                return [];
            }
            $query->whereIn('sp.admin_site_id', $siteIds);
        }

        return $query->limit(300)->get()->all();
    }

    /**
     * @return array<string, mixed>
     */
    private function formatCreditEntry(object $row, ?object $bill): array
    {
        $amount = (int) $row->amount;
        $billId = $bill !== null ? (int) $bill->id : null;

        return $this->baseRow(
            entryKind: 'credit',
            entryId: (int) $row->id,
            txnPrefix: 'CL',
            playerId: (int) $row->player_id,
            row: $row,
            bizType: (string) $row->reason,
            signedAmount: $amount,
            createdAt: $row->created_at,
            ledgerSource: 'credit_ledger',
            settlementBillId: $billId,
            billStatus: $bill !== null ? (string) $bill->status : null,
            billType: $bill !== null ? (string) $bill->bill_type : null,
            billUnpaid: $bill !== null ? (int) $bill->unpaid_amount : null,
        );
    }

    /**
     * @return array<string, mixed>
     */
    private function formatPaymentEntry(object $row): array
    {
        $amount = (int) $row->amount;

        return $this->baseRow(
            entryKind: 'payment',
            entryId: (int) $row->id,
            txnPrefix: 'PAY',
            playerId: (int) $row->player_id,
            row: $row,
            bizType: 'payment_record',
            signedAmount: $amount,
            createdAt: $row->created_at,
            ledgerSource: 'payment_record',
            settlementBillId: (int) $row->settlement_bill_id,
            billStatus: (string) ($row->bill_status ?? ''),
            billType: (string) ($row->bill_type ?? ''),
            billUnpaid: isset($row->unpaid_amount) ? (int) $row->unpaid_amount : null,
            refLabel: 'bill#'.$row->settlement_bill_id.($row->method ? ' · '.$row->method : ''),
        );
    }

    /**
     * @return array<string, mixed>
     */
    private function formatAdjustmentEntry(object $row): array
    {
        $amount = (int) $row->amount;
        $type = (string) $row->adjustment_type;

        return $this->baseRow(
            entryKind: 'adjustment',
            entryId: (int) $row->id,
            txnPrefix: 'ADJ',
            playerId: (int) $row->player_id,
            row: $row,
            bizType: $type,
            signedAmount: $amount,
            createdAt: $row->created_at,
            ledgerSource: 'settlement_adjustment',
            settlementBillId: (int) $row->settlement_bill_id,
            billStatus: (string) ($row->bill_status ?? ''),
            billType: (string) ($row->bill_type ?? ''),
            billUnpaid: isset($row->unpaid_amount) ? (int) $row->unpaid_amount : null,
            refLabel: $row->reason !== null && $row->reason !== ''
                ? (string) $row->reason
                : 'bill#'.$row->settlement_bill_id,
        );
    }

    /**
     * @return array<string, mixed>
     */
    private function baseRow(
        string $entryKind,
        int $entryId,
        string $txnPrefix,
        int $playerId,
        object $row,
        string $bizType,
        int $signedAmount,
        mixed $createdAt,
        string $ledgerSource,
        ?int $settlementBillId,
        ?string $billStatus,
        ?string $billType,
        ?int $billUnpaid,
        ?string $refLabel = null,
    ): array {
        $amountAbs = abs($signedAmount);
        $currency = (string) ($row->default_currency ?? '');

        return [
            'entry_kind' => $entryKind,
            'id' => $entryId,
            'row_key' => $entryKind.'-'.$entryId,
            'txn_no' => $txnPrefix.'-'.$entryId,
            'player_id' => $playerId,
            'site_code' => $row->site_code ?? null,
            'site_player_id' => $row->site_player_id ?? null,
            'username' => $row->username ?? null,
            'nickname' => $row->nickname ?? null,
            'biz_type' => $bizType,
            'biz_no' => $refLabel ?? $this->creditRefLabel($row),
            'direction' => $signedAmount >= 0 ? 1 : 2,
            'amount' => $amountAbs,
            'amount_formatted' => CurrencyFormatter::fromMinor($amountAbs),
            'signed_amount' => $signedAmount,
            'currency_code' => $currency,
            'status' => 'posted',
            'created_at' => $createdAt !== null ? Carbon::parse($createdAt)->toIso8601String() : null,
            'ledger_source' => $ledgerSource,
            'funding_mode' => (string) ($row->funding_mode ?? PlayerFundingMode::CREDIT),
            'auth_source' => $row->auth_source ?? null,
            'settlement_bill_id' => $settlementBillId,
            'bill_status' => $billStatus,
            'bill_type' => $billType,
            'bill_unpaid_amount' => $billUnpaid,
            'available_actions' => $this->resolveActions(
                $entryKind,
                $settlementBillId,
                $billStatus,
                $billType,
                $billUnpaid,
            ),
        ];
    }

    /**
     * @return list<string>
     */
    private function resolveActions(
        string $entryKind,
        ?int $billId,
        ?string $billStatus,
        ?string $billType,
        ?int $billUnpaid,
    ): array {
        $actions = ['view_player'];

        if ($billId === null || $billId <= 0) {
            return $actions;
        }

        $actions[] = 'view_bill';

        if ($billStatus === 'pending_confirm') {
            $actions[] = 'confirm';
        }

        if ($billStatus !== null
            && in_array($billStatus, ['confirmed', 'partial_paid', 'overdue'], true)
            && ($billUnpaid ?? 0) > 0) {
            $actions[] = 'payment';
        }

        if ($billStatus !== null
            && in_array($billStatus, ['confirmed', 'partial_paid', 'settled', 'overdue'], true)
            && ! in_array((string) $billType, ['adjustment', 'reversal', 'bad_debt'], true)) {
            $actions[] = 'adjustment';
            $actions[] = 'reversal';
        }

        if ($billStatus !== null
            && in_array($billStatus, ['confirmed', 'partial_paid', 'overdue'], true)
            && ($billUnpaid ?? 0) > 0
            && ! in_array((string) $billType, ['adjustment', 'reversal', 'bad_debt'], true)) {
            $actions[] = 'bad_debt';
        }

        return array_values(array_unique($actions));
    }

    private function creditRefLabel(object $row): ?string
    {
        if (! isset($row->ref_type) || $row->ref_type === null || $row->ref_id === null) {
            return null;
        }

        return (string) $row->ref_type.'#'.$row->ref_id;
    }
}