<?php

namespace App\Http\Controllers;

use App\Models\ModelPricing;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Validator;

class ModelPricingController extends Controller
{
    /**
     * Display a listing of model pricing
     */
    public function index()
    {
        $modelPricing = ModelPricing::orderBy('model_key')
            ->paginate(20);

        return view('model-pricing.index', compact('modelPricing'));
    }

    /**
     * Show the form for creating a new model pricing
     */
    public function create()
    {
        return view('model-pricing.create');
    }

    /**
     * Store a newly created model pricing
     */
    public function store(Request $request)
    {
        $validated = $request->validate([
            'model_key' => 'required|string|max:255|unique:model_pricing,model_key',
            'input_price_per_million' => 'required|numeric|min:0',
            'output_price_per_million' => 'required|numeric|min:0',
        ]);

        ModelPricing::create($validated);

        return redirect()
            ->route('model-pricing.index')
            ->with('success', 'Model pricing created successfully!');
    }

    /**
     * Display the specified model pricing
     */
    public function show(string $modelKey)
    {
        $model = ModelPricing::findOrFail($modelKey);

        return view('model-pricing.show', compact('model'));
    }

    /**
     * Show the form for editing the specified model pricing
     */
    public function edit(string $modelKey)
    {
        $model = ModelPricing::findOrFail($modelKey);

        return view('model-pricing.edit', compact('model'));
    }

    /**
     * Update the specified model pricing
     */
    public function update(Request $request, string $modelKey)
    {
        $model = ModelPricing::findOrFail($modelKey);

        $validated = $request->validate([
            'input_price_per_million' => 'required|numeric|min:0',
            'output_price_per_million' => 'required|numeric|min:0',
        ]);

        $model->update($validated);

        return redirect()
            ->route('model-pricing.index')
            ->with('success', 'Model pricing updated successfully!');
    }

    /**
     * Remove the specified model pricing
     */
    public function destroy(string $modelKey)
    {
        $model = ModelPricing::findOrFail($modelKey);
        $model->delete();

        return redirect()
            ->route('model-pricing.index')
            ->with('success', 'Model pricing deleted successfully!');
    }

    /**
     * Show the cost calculator
     */
    public function calculator()
    {
        $models = ModelPricing::orderBy('model_key')->get();

        return view('model-pricing.calculator', compact('models'));
    }

    /**
     * Calculate cost based on input
     */
    public function calculate(Request $request)
    {
        $validated = $request->validate([
            'model_key' => 'required|exists:model_pricing,model_key',
            'input_tokens' => 'required|integer|min:0',
            'output_tokens' => 'required|integer|min:0',
        ]);

        $model = ModelPricing::findOrFail($validated['model_key']);
        $cost = $model->calculateCost(
            $validated['input_tokens'],
            $validated['output_tokens']
        );

        return response()->json([
            'model' => $model->model_key,
            'input_tokens' => $validated['input_tokens'],
            'output_tokens' => $validated['output_tokens'],
            'total_tokens' => $validated['input_tokens'] + $validated['output_tokens'],
            'cost' => $cost,
            'cost_formatted' => '$' . number_format($cost, 6),
        ]);
    }

    /**
     * Show CSV import form
     */
    public function importForm()
    {
        return view('model-pricing.import');
    }

    /**
     * Import model pricing from CSV
     */
    public function import(Request $request)
    {
        $request->validate([
            'csv_file' => 'required|file|mimes:csv,txt|max:2048',
        ]);

        $file = $request->file('csv_file');
        $handle = fopen($file->getRealPath(), 'r');

        $imported = 0;
        $updated = 0;
        $errors = [];

        // Skip header row
        fgetcsv($handle);

        while (($row = fgetcsv($handle)) !== false) {
            if (count($row) < 3) {
                continue; // Skip invalid rows
            }

            $modelKey = trim($row[0]);
            $inputPrice = floatval($row[1]);
            $outputPrice = floatval($row[2]);

            if (empty($modelKey) || $inputPrice < 0 || $outputPrice < 0) {
                $errors[] = "Invalid data for model: {$modelKey}";
                continue;
            }

            $existing = ModelPricing::find($modelKey);

            if ($existing) {
                $existing->update([
                    'input_price_per_million' => $inputPrice,
                    'output_price_per_million' => $outputPrice,
                ]);
                $updated++;
            } else {
                ModelPricing::create([
                    'model_key' => $modelKey,
                    'input_price_per_million' => $inputPrice,
                    'output_price_per_million' => $outputPrice,
                ]);
                $imported++;
            }
        }

        fclose($handle);

        $message = "Import completed! Created: {$imported}, Updated: {$updated}";
        
        if (count($errors) > 0) {
            $message .= '. Errors: ' . implode(', ', array_slice($errors, 0, 5));
        }

        return redirect()
            ->route('model-pricing.index')
            ->with('success', $message);
    }
}