<?php
// scanner.php

require_once 'db/config.php';
require_once 'includes/finance_api.php';

header('Content-Type: application/json');

// --- Scanner Criteria ---
// Get criteria from POST request, with defaults
$min_market_cap = isset($_POST['min_market_cap']) ? (float)$_POST['min_market_cap'] : 50000000;
$max_market_cap = isset($_POST['max_market_cap']) ? (float)$_POST['max_market_cap'] : 10000000000;
$min_price = isset($_POST['min_price']) ? (float)$_POST['min_price'] : 1.00;
$min_volume = isset($_POST['min_volume']) ? (int)$_POST['min_volume'] : 100000;

$results = [];
$errors = [];

// 1. Fetch all listed stocks (as CSV)
$csv_data = get_all_listed_stocks();

if (is_array($csv_data) && isset($csv_data['error'])) {
    echo json_encode(['error' => $csv_data['error']]);
    exit;
}

$lines = str_getcsv($csv_data, "\n");
$header = str_getcsv(array_shift($lines));
$stocks = [];
foreach ($lines as $line) {
    if (empty(trim($line))) continue;
    $stocks[] = array_combine($header, str_getcsv($line));
}

// 2. Take a small, random sample to avoid hitting API limits
shuffle($stocks);
$sample_size = 5; // Limit to 5 API calls per scan to stay within free tier limits
$sample = array_slice($stocks, 0, $sample_size);

// 3. Analyze the sample
foreach ($sample as $stock) {
    $symbol = $stock['symbol'];

    // Skip non-US stocks for now for data consistency
    if (!in_array($stock['exchange'], ['NASDAQ', 'NYSE', 'AMEX'])) {
        continue;
    }

    // To avoid hitting API limits, wait between calls.
    // The free tier is very restrictive (5 calls/min).
    sleep(15);

    $overview = get_stock_overview($symbol);

    if (isset($overview['error'])) {
        $errors[] = "Could not fetch data for {$symbol}: " . $overview['error'];
        continue;
    }

    $market_cap = (float)($overview['MarketCapitalization'] ?? 0);
    $price = 0; // We'll get price from the quote call

    $volume_str = $overview['Volume'] ?? '0';
    $volume = (int) $volume_str;

    // Check market cap and volume first to avoid unnecessary price checks
    if ($market_cap >= $min_market_cap && $market_cap <= $max_market_cap && $volume >= $min_volume) {
        sleep(15); // Another wait before the next API call
        $quote = get_stock_quote($symbol);
        
        if (isset($quote['Global Quote']['05. price'])) {
            $price = (float)$quote['Global Quote']['05. price'];

            if ($price >= $min_price) {
                $results[] = [
                    'symbol' => $symbol,
                    'company_name' => $overview['Name'] ?? 'N/A',
                    'price' => $price,
                    'market_cap' => $market_cap
                ];
            }
        }
    }
}

if (!empty($errors)) {
    // If there were non-fatal errors, we can return them for debugging
    // For now, we just return the successful results.
}

echo json_encode($results);