<?php

namespace App\Filament\Imports;

use App\Models\Block;
use App\Models\Item;
use App\Models\Line;
use App\Models\Plant;
use App\Models\ProductionCalendar;
use App\Models\ProductionPlan;
use App\Models\Shift;
use App\Models\User;
use Carbon\Carbon;
use Filament\Actions\Imports\Exceptions\RowImportFailedException;
use Filament\Actions\Imports\ImportColumn;
use Filament\Actions\Imports\Importer;
use Filament\Actions\Imports\Models\Import;
use Filament\Facades\Filament;
use Str;
use Illuminate\Support\Facades\Log;

class ProductionPlanImporter extends Importer
{
    protected static ?string $model = ProductionPlan::class;

    public static function getColumns(): array
    {
        return [
            // ImportColumn::make('created_at')
            //     ->requiredMapping()
            //     ->exampleHeader('Created DateTime')
            //     ->example(['01-01-2025 08:00:00', '01-01-2025 19:30:00'])
            //     ->label('Created DateTime')
            //     ->rules(['required']),

            ImportColumn::make('plant')
                ->requiredMapping()
                ->exampleHeader('Plant Code')
                ->example(['1000'])
                ->label('Plant Code')
                ->relationship(resolveUsing: 'code')
                ->rules(['required']),
            // ImportColumn::make('line')
            //     ->requiredMapping()
            //     ->exampleHeader('Line Name')
            //     ->example(['4 inch pump line', '4 inch pump line'])
            //     ->label('Line Name')
            //     ->relationship(resolveUsing: 'name')
            //     ->rules(['required']),
            ImportColumn::make('item')
                ->requiredMapping()
                ->exampleHeader('Item Code')
                ->example(['123456'])
                ->label('Item Code')
                ->relationship(resolveUsing: 'code')
                ->rules(['required']),
            // ImportColumn::make('plan_quantity')
            //     ->requiredMapping()
            //     ->exampleHeader('Plan Quantity')
            //     ->example(['500', '450'])
            //     ->label('Plan Quantity')
            //     ->numeric()
            //     ->rules(['required', 'integer']),
            ImportColumn::make('week_1')
                ->requiredMapping()
                ->exampleHeader('Week 1')
                ->label('Week 1'),
            ImportColumn::make('week_2')
                ->requiredMapping()
                ->exampleHeader('Week 2')
                ->label('Week 2'),
            ImportColumn::make('week_3')
                ->requiredMapping()
                ->exampleHeader('Week 3')
                ->label('Week 3'),
            ImportColumn::make('week_4')
                ->requiredMapping()
                ->exampleHeader('Week 4')
                ->label('Week 4'),
            ImportColumn::make('week_5')
                ->requiredMapping()
                ->exampleHeader('Week 5')
                ->label('Week 5'),
            // ImportColumn::make('production_quantity')
            //     ->requiredMapping()
            //     ->exampleHeader('Production Quantity')
            //     ->example(['0', '0'])
            //     ->label('Production Quantity')
            //     ->numeric()
            //     ->rules(['required', 'integer']),

            // ImportColumn::make('block_reference')
            //     ->requiredMapping() // Or optionalMapping() if not always present
            //     ->exampleHeader('Block Name')
            //     ->example(['Block A', 'Block A'])
            //     ->label('Block Name')
            //     ->rules(['required']), // Or remove if not required
            // ImportColumn::make('shift')
            //     ->requiredMapping()
            //     ->exampleHeader('Shift Name') // ID
            //     ->example(['Day', 'Night']) // '2', '7'
            //     ->label('Shift Name') // ID
            //     ->relationship(resolveUsing: 'name')
            //     ->rules(['required']),

            // ImportColumn::make('updated_at')
            //     ->requiredMapping()
            //     ->exampleHeader('Updated DateTime')
            //     ->example(['01-01-2025 08:00:00', '01-01-2025 19:30:00'])
            //     ->label('Updated DateTime')
            //     ->rules(['required']),
            // ImportColumn::make('operator_id')
            //     ->requiredMapping()
            //     ->exampleHeader('Operator ID')
            //     ->example([Filament::auth()->user()->name, Filament::auth()->user()->name])
            //     ->label('Operator ID')
            //     ->rules(['required']),
        ];
    }

    public function resolveRecord(): ?ProductionPlan
    {
        $warnMsg = [];
        $plantCod = $this->data['plant'];
        $itemCod = $this->data['item'];
        $plant = null;
        $line = null;
        $block = null;

        if (Str::length($plantCod) < 4 || ! is_numeric($plantCod) || ! preg_match('/^[1-9]\d{3,}$/', $plantCod)) {
            $warnMsg[] = 'Invalid plant code found';
        } else {
            $plant = Plant::where('code', $plantCod)->first();
        }

        if (! $plant) {
            $warnMsg[] = 'Plant not found';
        }

        if (Str::length($itemCod) < 6 || ! is_numeric($itemCod)) {
            $warnMsg[] = 'Invalid item code found';
        } else {
            $item = Item::where('code', $itemCod)->first();
        }

        if (! $item) {
            $warnMsg[] = 'Item not found';
        }

        $plantId = $plant->id;

        $itemAgaPlant = Item::where('plant_id', $plantId)->where('code', $itemCod)->first();

        if(!$itemAgaPlant){
            $warnMsg[] = 'Item not found against plant code';
        }
        else {
            $line = $itemAgaPlant->line_id;

            if (!$line) {
                $warnMsg[] = 'Line not mapped for that item code';
            }
        }

        $user = Filament::auth()->user();

        $operatorName = $user->name;

        if (!empty($this->data['plan_quantity'])) {
            if (Str::length($this->data['plan_quantity']) < 0 || ! is_numeric($this->data['plan_quantity']) || $this->data['plan_quantity'] <= 0) {
                $warnMsg[] = 'Invalid plan quantity found';
            }
        }

        foreach (['week_1', 'week_2', 'week_3', 'week_4'] as $week) {
            $value = $this->data[$week] ?? null;

            if (filled($value) && (! is_numeric($value) || $value < 0)) {
                $warnMsg[] = "Invalid {$week} value found";
            }
        }

        $week5 = $this->data['week_5'] ?? null;

        if (
            filled($week5) &&
            (! is_numeric($week5) || $week5 < 0)
        ) {
            $warnMsg[] = 'Invalid week_5 value found';
        }

        $recordDate = now();
        $month = $recordDate->month;
        $year = $recordDate->year;

        $previousRecord = ProductionCalendar::where('plant_id', $plant->id)
            ->whereMonth('created_at', $month)
            ->whereYear('created_at', $year)
            ->first();

        if(!$previousRecord){
            $warnMsg[] = 'Update this month production calendar';
        }

        if (! empty($warnMsg)) {
            throw new RowImportFailedException(implode(', ', $warnMsg));
        }


        $recordDate = now();
        $month = $recordDate->month;
        $year = $recordDate->year;

        $totalDays = $recordDate->daysInMonth;

        $previousRecord = ProductionCalendar::where('plant_id', $plant->id)
            ->whereMonth('created_at', $month)
            ->whereYear('created_at', $year)
            ->first();

        $workingDays = $previousRecord?->working_days ?? null;

        // Get leave dates
        $leaveDates = array_filter(
            array_map(
                'trim',
                explode(',', (string) ($previousRecord?->leave_dates ?? ''))
            )
        );

        // Convert leave dates into day numbers
        $leaveDayNumbers = [];

        foreach ($leaveDates as $leaveDate) {
            try {
                $date = Carbon::parse($leaveDate);

                if ($date->format('Y-m') === $recordDate->format('Y-m')) {
                    $leaveDayNumbers[] = (int) $date->format('d');
                }
            } catch (\Throwable $e) {
                // Ignore invalid leave dates
            }
        }

        // Get existing production plan for this item
        $productionPlan1 = ProductionPlan::where('plant_id', $plant->id)
            ->where('item_id', $itemAgaPlant->id)
            ->whereYear('created_at', $year)
            ->whereMonth('created_at', $month)
            ->first();

        // Initialize daily data
        $dailyData = [];

        for ($day = 1; $day <= 31; $day++) {

            if ($day <= $totalDays) {
                $dailyData['day_' . $day] =
                    (int) ($productionPlan1->{'day_' . $day} ?? 0);
            } else {
                // Invalid dates must always remain zero
                $dailyData['day_' . $day] = 0;
            }
        }

        // Weekly ranges
        $weekRanges = [
            'week_1' => [1, min(7, $totalDays)],
            'week_2' => [8, min(14, $totalDays)],
            'week_3' => [15, min(21, $totalDays)],
            'week_4' => [22, min(28, $totalDays)],
            'week_5' => [29, min(31, $totalDays)],
        ];

        // Process weekly values
        foreach ($weekRanges as $week => [$start, $end]) {

            if ($start > $totalDays) {
                continue;
            }

            $weeklyValue = $this->data[$week] ?? null;

            // Empty Excel value: retain existing daily values
            if ($weeklyValue === null || $weeklyValue === '') {
                continue;
            }

            // Get working days excluding leave dates
            $remainingDays = [];

            for ($day = $start; $day <= $end; $day++) {

                if (! in_array($day, $leaveDayNumbers, true)) {
                    $remainingDays[] = $day;
                } else {
                    $dailyData['day_' . $day] = 0;
                }
            }

            $daysCount = count($remainingDays);

            if ($daysCount === 0) {
                continue;
            }

            // Replace existing weekly quantity with Excel quantity
            $weeklyTotal = (int) round((float) $weeklyValue);

            $dailyValue = intdiv($weeklyTotal, $daysCount);
            $remainder = $weeklyTotal % $daysCount;

            foreach ($remainingDays as $index => $day) {

                $dailyData['day_' . $day] =
                    $dailyValue + ($index < $remainder ? 1 : 0);
            }
        }

        // Calculate final monthly plan quantity
        $planQuantity = array_sum($dailyData);

        // Prepare plan data
        $planData = array_merge([
            'line_id' => $line,
            'plan_quantity' => $planQuantity,
            'working_days' => $workingDays,
            'operator_id' => $operatorName,
            'updated_at' => now(),
        ], $dailyData);

        // Update or create production plan
        if ($productionPlan1) {

            $productionPlan1->update($planData);

        } else {

            ProductionPlan::create(array_merge($planData, [
                'plant_id' => $plant->id,
                'item_id' => $itemAgaPlant->id,
                'created_at' => now(),
            ]));

        }


        //..Working Logic

        // $recordDate = now();
        // $month = $recordDate->month;
        // $year = $recordDate->year;

        // $previousRecord = ProductionPlan::where('plant_id', $plant->id)
        //     ->whereMonth('created_at', $month)
        //     ->whereYear('created_at', $year)
        //     ->first();

        // $workingDays = $previousRecord?->working_days ?? null;

        // // Get leave dates from the existing production plan
        // $leaveDates = array_filter(
        //     array_map('trim', explode(',', (string) ($previousRecord?->leave_dates ?? '')))
        // );

        // // Convert leave dates into day numbers for the current month
        // $leaveDayNumbers = [];

        // foreach ($leaveDates as $leaveDate) {
        //     $date = Carbon::parse($leaveDate);

        //     if ($date->format('Y-m') === $recordDate->format('Y-m')) {
        //         $leaveDayNumbers[] = (int) $date->format('d');
        //     }
        // }

        // $totalDays = $recordDate->daysInMonth;

        // $dailyData = [];

        // for ($day = 1; $day <= 31; $day++) {
        //     $dailyData['day_' . $day] = 0;
        // }

        // $planQuantity = 0;

        // foreach (['week_1', 'week_2', 'week_3', 'week_4', 'week_5'] as $week) {
        //     $planQuantity += (float) ($this->data[$week] ?? 0);
        // }

        // $planQuantity = (int) $planQuantity;

        // // Dynamic weekly ranges
        // $weekRanges = [
        //     'week_1' => [1, min(7, $totalDays)],
        //     'week_2' => [8, min(14, $totalDays)],
        //     'week_3' => [15, min(21, $totalDays)],
        //     'week_4' => [22, min(28, $totalDays)],
        //     'week_5' => [29, min(31, $totalDays)],
        // ];

        // foreach ($weekRanges as $week => [$start, $end]) {

        //     if ($start > $totalDays) {
        //         continue;
        //     }

        //     $weeklyValue = $this->data[$week] ?? null;

        //     if ($weeklyValue === null || $weeklyValue === '') {
        //         continue;
        //     }

        //     $remainingDays = [];

        //     for ($day = $start; $day <= $end; $day++) {
        //         if (! in_array($day, $leaveDayNumbers)) {
        //             $remainingDays[] = $day;
        //         }
        //     }

        //     $daysCount = count($remainingDays);

        //     if ($daysCount === 0) {
        //         continue;
        //     }

        //     $weeklyTotal = (int) round((float) $weeklyValue);

        //     $dailyValue = intdiv($weeklyTotal, $daysCount);
        //     $remainder = $weeklyTotal % $daysCount;

        //     foreach ($remainingDays as $index => $day) {
        //         $dailyData['day_' . $day] =
        //             $dailyValue + ($index < $remainder ? 1 : 0);
        //     }
        // }

        // $dailyTotal = array_sum($dailyData);

        // $productionPlan1 = ProductionPlan::where('plant_id', $plant->id)
        //     ->where('item_id', $itemAgaPlant->id)
        //     ->whereYear('created_at', $recordDate->year)
        //     ->whereMonth('created_at', $recordDate->month)
        //     ->first();

        // $planData = array_merge([
        //     'line_id' => $line,
        //     'plan_quantity' => $planQuantity,
        //     'working_days' => $workingDays,
        //     'operator_id' => $operatorName,
        //     'updated_at' => now(),
        // ], $dailyData);

        // if ($productionPlan1) {

        //     $productionPlan1->update($planData);

        // } else {

        //     ProductionPlan::create(array_merge($planData, [
        //         'plant_id' => $plant->id,
        //         'item_id' => $itemAgaPlant->id,
        //         'created_at' => now(),
        //     ]));

        // }

        //..Old Logic

        // $productionPlan1 = ProductionPlan::where('plant_id', $plant->id)
        //     ->where('item_id', $itemAgaPlant->id)
        //     ->whereYear('created_at', $recordDate->year)
        //     ->whereMonth('created_at', $recordDate->month)
        //     ->first();

        // if ($productionPlan1) {
        //     $productionPlan1->update([
        //         'line_id' => $line,
        //         'plan_quantity' => $this->data['plan_quantity'],
        //         'working_days' => $workingDays,
        //         'operator_id' => $operatorName,
        //         'updated_at' => now(),
        //     ]);
        // } else {
        //     ProductionPlan::create([
        //         'plant_id' => $plant->id,
        //         'line_id' => $line,
        //         'item_id' => $itemAgaPlant->id,
        //         'plan_quantity' => $this->data['plan_quantity'],
        //         'working_days' => $workingDays,
        //         'operator_id' => $operatorName,
        //         'created_at' => now(),
        //         'updated_at' => now(),
        //     ]);
        // }

        return null;
    }

    public static function getCompletedNotificationBody(Import $import): string
    {
        $body = 'Your production plan import has completed and '.number_format($import->successful_rows).' '.str('row')->plural($import->successful_rows).' imported.';

        if ($failedRowsCount = $import->getFailedRowsCount()) {
            $body .= ' '.number_format($failedRowsCount).' '.str('row')->plural($failedRowsCount).' failed to import.';
        }

        return $body;
    }
}