<?php

namespace Modules\EcommerceFinance\Services;

use App\Utilities\FinanceLedgerIndependentAccounts;
use Carbon\CarbonImmutable;
use Illuminate\Database\ConnectionInterface;
use Illuminate\Database\DatabaseManager;
use InvalidArgumentException;
use PhpOffice\PhpSpreadsheet\IOFactory;

/**
 * 导入朱俊祥微信月度收支表。
 *
 * 工作簿使用“日期、简称、收入、支出、余额”五列；首笔余额单独一行、
 * 日期为空，作为该月期初。每一笔余额必须按上一笔余额加收支滚动对平。
 */
class WechatStatementImporter
{
    public const SOURCE = 'wechat-statement';

    public const PROCESS_TYPE = '公司微信收支流水';

    public const DEFAULT_ACCOUNT_SHORT = '朱俊祥微信';

    private readonly ConnectionInterface $connection;

    public function __construct(
        DatabaseManager $databases,
        private readonly FinanceLedgerCalculator $calculator,
    ) {
        $this->connection = $databases->connection(
            (string) config('upstream_mirrors.connection', 'business_mirror'),
        );
    }

    /**
     * @return array<string,mixed>
     */
    public function import(
        string $path,
        ?string $accountShort = null,
        ?float $openingBalance = null,
        bool $dryRun = false,
    ): array {
        if (! is_file($path) || ! is_readable($path)) {
            throw new InvalidArgumentException('微信收支表文件不存在或不可读取。');
        }

        $accountShort = trim((string) ($accountShort ?: self::DEFAULT_ACCOUNT_SHORT));
        if (! FinanceLedgerIndependentAccounts::contains($accountShort)) {
            throw new InvalidArgumentException('微信月度收支表只能导入独立账单账户。');
        }
        if (! $this->connection->table('fin_accounts')->where('account_short', $accountShort)->exists()) {
            throw new InvalidArgumentException('账户总表中没有账户：' . $accountShort);
        }

        [$fileOpening, $rows] = $this->rows($path, $accountShort);
        if ($rows === []) {
            throw new InvalidArgumentException('微信收支表中没有有效明细。');
        }
        if ($openingBalance !== null && abs(round($openingBalance, 2) - $fileOpening) > 0.001) {
            throw new InvalidArgumentException(sprintf(
                '期初余额不一致：指定 %.2f，文件为 %.2f。',
                $openingBalance,
                $fileOpening,
            ));
        }
        $openingBalance = $openingBalance === null ? $fileOpening : round($openingBalance, 2);

        $income = round(array_sum(array_column($rows, 'income')), 2);
        $expense = round(array_sum(array_column($rows, 'expense')), 2);
        $closingBalance = round((float) $rows[array_key_last($rows)]['balance'], 2);
        $expectedClosing = round($openingBalance + $income - $expense, 2);
        if (abs($expectedClosing - $closingBalance) > 0.001) {
            throw new InvalidArgumentException(sprintf(
                '微信收支未对平：期初加收支应为 %.2f，末笔余额为 %.2f。',
                $expectedClosing,
                $closingBalance,
            ));
        }

        $firstDate = (string) $rows[0]['txn_date'];
        $lastDate = (string) $rows[array_key_last($rows)]['txn_date'];
        $from = CarbonImmutable::parse($firstDate)->startOfMonth()->toDateString();
        $to = CarbonImmutable::parse($lastDate)->endOfMonth()->toDateString();
        $replaceCount = (int) $this->connection->table('fin_transactions')
            ->where('source', self::SOURCE)
            ->where('source_value', $accountShort)
            ->whereBetween('txn_date', [$from, $to])
            ->count();

        $result = [
            'dry_run' => $dryRun,
            'account_short' => $accountShort,
            'from' => $from,
            'to' => $to,
            'opening_balance' => $openingBalance,
            'closing_balance' => $closingBalance,
            'rows' => count($rows),
            'income' => $income,
            'expense' => $expense,
            'replaced' => $replaceCount,
            'recalculated' => null,
        ];
        if ($dryRun) {
            return $result;
        }

        $result['recalculated'] = $this->connection->transaction(function () use (
            $accountShort,
            $from,
            $to,
            $openingBalance,
            $rows,
        ): array {
            $this->connection->table('fin_transactions')
                ->where('source', self::SOURCE)
                ->where('source_value', $accountShort)
                ->whereBetween('txn_date', [$from, $to])
                ->delete();
            foreach (array_chunk($rows, 500) as $chunk) {
                $this->connection->table('fin_transactions')->insert($chunk);
            }

            $now = now();
            $this->connection->table('fin_account_opening')
                ->where('account_short', $accountShort)
                ->delete();
            $this->connection->table('fin_account_opening')->insert([
                'account_short' => $accountShort,
                'opening_date' => $from,
                'opening_balance' => $openingBalance,
                'remark' => '微信月度收支表期初',
                'created_at' => $now,
                'updated_at' => $now,
            ]);
            $this->connection->table('fin_account_map')->updateOrInsert(
                ['source' => self::SOURCE, 'source_value' => $accountShort],
                [
                    'account_short' => $accountShort,
                    'txn_count' => count($rows),
                    'income_sum' => round(array_sum(array_column($rows, 'income')), 2),
                    'expense_sum' => round(array_sum(array_column($rows, 'expense')), 2),
                    'updated_by' => '系统自动同步',
                    'updated_at' => $now,
                    'created_at' => $now,
                ],
            );

            return $this->calculator->recalculate();
        });

        return $result;
    }

    /**
     * @return array{0:float,1:list<array<string,mixed>>}
     */
    private function rows(string $path, string $accountShort): array
    {
        $spreadsheet = IOFactory::load($path);
        $matrix = $spreadsheet->getActiveSheet()->toArray(null, true, true, false);
        $spreadsheet->disconnectWorksheets();
        $headerIndex = null;
        foreach ($matrix as $index => $row) {
            $headers = array_map(fn (mixed $value): string => $this->header((string) $value), $row);
            if (in_array('日期', $headers, true)
                && in_array('收入', $headers, true)
                && in_array('支出', $headers, true)
                && in_array('余额', $headers, true)) {
                $headerIndex = $index;
                break;
            }
        }
        if ($headerIndex === null) {
            throw new InvalidArgumentException('未找到微信收支表头：日期、收入、支出、余额。');
        }

        $headers = array_map(fn (mixed $value): string => $this->header((string) $value), $matrix[$headerIndex]);
        $indexes = [];
        foreach (['date' => '日期', 'account' => '简称', 'income' => '收入', 'expense' => '支出', 'balance' => '余额'] as $key => $label) {
            $position = array_search($label, $headers, true);
            if ($position === false) {
                throw new InvalidArgumentException('微信收支表缺少字段：' . $label);
            }
            $indexes[$key] = $position;
        }

        $opening = null;
        $rows = [];
        $previousBalance = null;
        $occurrences = [];
        foreach (array_slice($matrix, $headerIndex + 1, null, true) as $rowIndex => $values) {
            $value = static fn (string $key): string => trim((string) ($values[$indexes[$key]] ?? ''));
            $balance = $value('balance');
            if ($opening === null && $value('date') === '' && $balance !== '') {
                $opening = $this->money($balance);
                $previousBalance = $opening;
                continue;
            }
            if ($value('date') === '') {
                continue;
            }

            $date = $this->date($value('date'));
            $income = $value('income') === '' ? 0.0 : $this->money($value('income'));
            $expense = $value('expense') === '' ? 0.0 : $this->money($value('expense'));
            if (($income > 0) === ($expense > 0)) {
                throw new InvalidArgumentException('微信收支第 ' . ($rowIndex + 1) . ' 行必须且只能填写收入或支出。');
            }
            if ($balance === '') {
                throw new InvalidArgumentException('微信收支第 ' . ($rowIndex + 1) . ' 行缺少余额。');
            }
            $balanceValue = $this->money($balance);
            if ($previousBalance !== null) {
                $expected = round($previousBalance + $income - $expense, 2);
                if (abs($expected - $balanceValue) > 0.001) {
                    throw new InvalidArgumentException(sprintf(
                        '微信收支第 %d 行余额未对平：应为 %.2f，实际 %.2f。',
                        $rowIndex + 1,
                        $expected,
                        $balanceValue,
                    ));
                }
            }
            $previousBalance = $balanceValue;

            $occurrenceKey = implode("\0", [$date, $income, $expense, $balanceValue]);
            $occurrences[$occurrenceKey] = ($occurrences[$occurrenceKey] ?? 0) + 1;
            $now = now();
            $rows[] = [
                'txn_date' => $date,
                'account_short' => $accountShort,
                'counterparty_info' => null,
                'detail' => '朱俊祥微信收支',
                'income' => $income,
                'expense' => $expense,
                'balance' => $balanceValue,
                'approval_no' => 'WX-' . str_replace('-', '', $date) . '-' . str_pad((string) ($rowIndex + 1), 4, '0', STR_PAD_LEFT),
                'payment_remark' => null,
                'source' => self::SOURCE,
                'source_value' => $accountShort,
                'process_type' => self::PROCESS_TYPE,
                'row_key' => hash('sha256', implode("\0", [
                    self::SOURCE,
                    $accountShort,
                    $occurrenceKey,
                    $occurrences[$occurrenceKey],
                ])),
                'synced_at' => $now,
                'created_at' => $now,
                'updated_at' => $now,
                'created_by' => '系统自动同步',
                'updated_by' => '系统自动同步',
            ];
        }

        if ($opening === null) {
            throw new InvalidArgumentException('微信收支表未找到期初余额行。');
        }

        return [round($opening, 2), $rows];
    }

    private function date(string $value): string
    {
        foreach (['!n/j/Y', '!Y-m-d', '!Y/m/d'] as $format) {
            $date = CarbonImmutable::createFromFormat($format, trim($value));
            if ($date instanceof CarbonImmutable && $date->format(ltrim($format, '!')) === trim($value)) {
                return $date->format('Y-m-d');
            }
        }
        if (is_numeric($value)) {
            return \PhpOffice\PhpSpreadsheet\Shared\Date::excelToDateTimeObject((float) $value)
                ->format('Y-m-d');
        }

        throw new InvalidArgumentException('微信收支日期格式无法识别：' . $value);
    }

    private function money(string $value): float
    {
        $text = trim(str_replace([',', '，', '¥', '￥', ' '], '', $value));

        return $text === '' ? 0.0 : round((float) $text, 2);
    }

    private function header(string $value): string
    {
        return preg_replace('/[\s　]+/u', '', trim($value)) ?? trim($value);
    }
}