<?php

namespace App\Http\Controllers;

use App\Models\IsrBracket;
use App\Models\IsrTable;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Log;
use Illuminate\Support\Facades\Validator;

class IsrController extends Controller
{
    /**
     * Lista todas las tablas ISR
     */
    public function index()
    {
        $isrTables = IsrTable::with('brackets')->orderBy('year', 'desc')->get();
        return view('settings.isr.index', compact('isrTables'));
    }

    /**
     * Crea nueva tabla por año
     */
    public function store(Request $request)
    {
        $validator = Validator::make($request->all(), [
            'year' => 'required|integer|min:2000|max:2100|unique:isr_tables,year',
        ]);

        if ($validator->fails()) {
            return redirect()->route('settings.index', ['tab' => 'isr'])
                ->withErrors($validator)
                ->withInput();
        }

        $isrTable = IsrTable::create([
            'year' => $request->input('year'),
        ]);

        return redirect()->route('settings.index', ['tab' => 'isr'])
            ->with('success', 'Tabla ISR para ' . $isrTable->year . ' creada. Ahora agrega los brackets.');
    }

    /**
     * Formulario edición de brackets
     */
    public function edit(IsrTable $isrTable)
    {
        $isrTable->load('brackets');
        return view('settings.isr.edit', compact('isrTable'));
    }

    /**
     * Guarda brackets manuales
     */
    public function updateBrackets(Request $request, IsrTable $isrTable)
    {
        $validator = Validator::make($request->all(), [
            'brackets' => 'required|array|min:1',
            'brackets.*.lower_limit' => 'required|numeric|min:0',
            'brackets.*.upper_limit' => 'nullable|numeric|min:0',
            'brackets.*.fixed_fee' => 'required|numeric|min:0',
            'brackets.*.rate' => 'required|numeric|min:0|max:100',
        ]);

        if ($validator->fails()) {
            return redirect()->route('settings.isr.edit', $isrTable)
                ->withErrors($validator)
                ->withInput();
        }

        // Eliminar brackets existentes
        $isrTable->brackets()->delete();

        // Crear nuevos brackets
        $bracketsData = $request->input('brackets');
        $order = 0;

        // Ordenar brackets por lower_limit antes de guardar
        usort($bracketsData, function ($a, $b) {
            return floatval($a['lower_limit']) - floatval($b['lower_limit']);
        });

        foreach ($bracketsData as $bracketData) {
            $isrTable->brackets()->create([
                'lower_limit' => floatval($bracketData['lower_limit']),
                'upper_limit' => isset($bracketData['upper_limit']) && $bracketData['upper_limit'] !== '' 
                    ? floatval($bracketData['upper_limit']) 
                    : null,
                'fixed_fee' => floatval($bracketData['fixed_fee']),
                'rate' => floatval($bracketData['rate']),
                'order' => $order++,
            ]);
        }

        return redirect()->route('settings.index', ['tab' => 'isr'])
            ->with('success', 'Brackets actualizados correctamente.');
    }

    /**
     * Importa CSV
     */
    public function uploadCsv(Request $request, IsrTable $isrTable)
    {
        $validator = Validator::make($request->all(), [
            'csv_file' => 'required|file|mimes:csv,txt',
        ]);

        if ($validator->fails()) {
            return redirect()->route('settings.isr.edit', $isrTable)
                ->withErrors($validator)
                ->withInput();
        }

        $file = $request->file('csv_file');
        $content = file_get_contents($file->getRealPath());
        $lines = explode("\n", $content);

        $brackets = [];
        $firstLine = true;

        foreach ($lines as $line) {
            $line = trim($line);

            // Ignorar primera línea (encabezados vacíos)
            if ($firstLine) {
                $firstLine = false;
                continue;
            }

            if (empty($line)) {
                continue;
            }

            // Parsear línea CSV
            $values = str_getcsv($line);

            if (count($values) < 4) {
                continue;
            }

            $lowerLimit = $this->parseCsvValue($values[0]);
            $upperLimit = $this->parseCsvValue($values[1]);
            $fixedFee = $this->parseCsvValue($values[2]);
            $rate = $this->parseCsvValue($values[3]);

            // Ignorar si no hay lower_limit válido
            if ($lowerLimit === null || $lowerLimit < 0) {
                continue;
            }

            // Default null values to 0
            $fixedFee = $fixedFee ?? 0;
            $rate = $rate ?? 0;

            $brackets[] = [
                'lower_limit' => $lowerLimit,
                'upper_limit' => $upperLimit,
                'fixed_fee' => $fixedFee,
                'rate' => $rate,
            ];
        }

        // Ordenar brackets por lower_limit
        usort($brackets, function ($a, $b) {
            return $a['lower_limit'] - $b['lower_limit'];
        });

        if (empty($brackets)) {
            return redirect()->route('settings.index', ['tab' => 'isr'])
                ->with('error', 'No se encontraron brackets válidos en el archivo CSV.');
        }

        // Eliminar brackets existentes
        $isrTable->brackets()->delete();

        // Crear nuevos brackets
        $order = 0;
        foreach ($brackets as $bracket) {
            $isrTable->brackets()->create([
                'lower_limit' => $bracket['lower_limit'],
                'upper_limit' => $bracket['upper_limit'],
                'fixed_fee' => $bracket['fixed_fee'],
                'rate' => $bracket['rate'],
                'order' => $order++,
            ]);
        }

        return redirect()->route('settings.index', ['tab' => 'isr'])
            ->with('success', 'Brackets importados correctamente desde el CSV.');
    }

    /**
     * Elimina tabla ISR
     */
    public function destroy(IsrTable $isrTable)
    {
        $year = $isrTable->year;
        $isrTable->delete();

        return redirect()->route('settings.index', ['tab' => 'isr'])
            ->with('success', 'Tabla ISR para ' . $year . ' eliminada.');
    }

    /**
     * Convierte valor CSV como "3,537.15" a 3537.15
     */
    private function parseCsvValue(string $val): ?float
    {
        // Limpiar comillas y espacios
        $val = trim($val, '"\' ');

        // Manejar "En adelante" como null
        if (in_array(strtolower($val), ['en adelante', 'en adelante ', 'null', ''])) {
            return null;
        }

        // Eliminar comas de miles
        $val = str_replace(',', '', $val);

        // Convertir a número
        $num = floatval($val);

        // Permitir 0 como valor válido, pero null para valores negativos o no numéricos
        return is_numeric($val) ? $num : null;
    }
}