<?php
namespace App\Services\Contabilita;

use Carbon\Carbon;

class MpsQifParser
{
    /**
     * @return array{rows: array<int, array{data: Carbon, valuta: Carbon|null, descrizione: string, descrizione_estesa?: string|null, importo: float, causale: string|null, raw_line: string}>, meta: array<string,mixed>}
     */
    public function parse(string $content): array
    {
        $content = str_replace(["\r\n", "\r"], "\n", $content);
        $lines   = array_values(array_filter(explode("\n", $content), static fn(string $line): bool => trim($line) !== ''));

        if ($lines === []) {
            throw new \RuntimeException('File QIF vuoto.');
        }

        $type        = null;
        $rows        = [];
        $transaction = [];

        foreach ($lines as $line) {
            $line    = preg_replace('/^\xEF\xBB\xBF/', '', $line) ?? $line;
            $trimmed = trim($line);

            if ($trimmed === '') {
                continue;
            }

            if (str_starts_with($trimmed, '!Type:')) {
                $type = substr($trimmed, 6) ?: null;
                continue;
            }

            if ($trimmed === '^') {
                $row = $this->buildRow($transaction, $type);
                if ($row !== null) {
                    $rows[] = $row;
                }
                $transaction = [];
                continue;
            }

            $code  = substr($trimmed, 0, 1);
            $value = trim(substr($trimmed, 1));

            if (! isset($transaction[$code])) {
                $transaction[$code] = [];
            }

            $transaction[$code][] = $value;
        }

        if ($transaction !== []) {
            $row = $this->buildRow($transaction, $type);
            if ($row !== null) {
                $rows[] = $row;
            }
        }

        if ($rows === []) {
            throw new \RuntimeException('Nessun movimento valido trovato nel file QIF.');
        }

        return [
            'rows' => $rows,
            'meta' => [
                'format'   => 'mps_qif',
                'qif_type' => $type,
            ],
        ];
    }

    /**
     * @param array<string, array<int, string>> $transaction
     * @return array{data: Carbon, valuta: Carbon|null, descrizione: string, descrizione_estesa?: string|null, importo: float, causale: string|null, raw_line: string}|null
     */
    private function buildRow(array $transaction, ?string $type): ?array
    {
        $date   = $this->parseDate($transaction['D'][0] ?? null);
        $amount = $this->parseMoney($transaction['T'][0] ?? null);

        if (! $date || $amount === null) {
            return null;
        }

        $payee       = $this->joinParts($transaction['P'] ?? []);
        $memo        = $this->joinParts($transaction['M'] ?? []);
        $description = $payee !== '' ? $payee : ($memo !== '' ? mb_substr($memo, 0, 255) : 'Movimento QIF');
        $extended    = trim($payee . ($payee !== '' && $memo !== '' ? ' · ' : '') . $memo);

        $rawLines = [];
        foreach ($transaction as $code => $values) {
            foreach ($values as $value) {
                $rawLines[] = $code . $value;
            }
        }

        return [
            'data'               => $date,
            'valuta'             => $date->copy(),
            'descrizione'        => $description,
            'descrizione_estesa' => $extended !== '' ? $extended : null,
            'importo'            => $amount,
            'causale'            => $type ? ('QIF:' . strtoupper($type)) : 'QIF',
            'raw_line'           => implode("\n", $rawLines),
        ];
    }

    /**
     * @param array<int, string> $parts
     */
    private function joinParts(array $parts): string
    {
        $parts = array_map(static fn(string $value): string => trim($value), $parts);
        $parts = array_values(array_filter($parts, static fn(string $value): bool => $value !== ''));

        return trim(implode(' ', $parts));
    }

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

        foreach (['d/m/Y', 'd/m/y', 'm/d/Y', 'm/d/y'] as $format) {
            try {
                return Carbon::createFromFormat($format, $value)->startOfDay();
            } catch (\Throwable) {
                // Try next format.
            }
        }

        return null;
    }

    private function parseMoney(?string $value): ?float
    {
        $value = trim((string) $value);
        if ($value === '') {
            return null;
        }

        $value = str_replace(["\u{00A0}", "\t", ' '], '', $value);
        $value = str_ireplace(['EUR', 'EURO', '€'], '', $value);
        $value = preg_replace('/[^0-9,\.\-\+]/', '', $value) ?? $value;

        if (str_contains($value, ',') && str_contains($value, '.')) {
            $value = str_replace('.', '', $value);
            $value = str_replace(',', '.', $value);
        } elseif (str_contains($value, ',')) {
            $value = str_replace(',', '.', $value);
        }

        return is_numeric($value) ? (float) $value : null;
    }
}