<?php
// includes/finance_api.php

function get_finance_api_key() {
    // For now, we'll use the demo key.
    // In the future, we can get this from an environment variable.
    return 'demo';
}

function call_finance_api($params) {
    $params['apikey'] = get_finance_api_key();
    $url = 'https://www.alphavantage.co/query?' . http_build_query($params);

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_TIMEOUT, 20); // 20 second timeout
    $response = curl_exec($ch);
    curl_close($ch);

    // Alpha Vantage returns CSV for listing status, and JSON for others.
    // The free API also sometimes returns a JSON error note about call frequency.
    if (strpos($response, 'Thank you for using Alpha Vantage!') !== false) {
        return ['error' => 'API call frequency limit reached. Please wait a minute and try again.'];
    }
    
    if (strpos($response, 'Invalid API call') !== false) {
        return ['error' => 'Invalid API call. Please check the symbol.'];
    }

    $data = json_decode($response, true);
    if (json_last_error() === JSON_ERROR_NONE) {
        if (isset($data['Note'])) {
            return ['error' => 'API call frequency limit reached. Please wait a minute and try again.'];
        }
        if (isset($data['Error Message'])) {
            return ['error' => $data['Error Message']];
        }
        return $data;
    }

    // If not JSON, assume it's CSV (for listing_status)
    return $response;
}

function get_all_listed_stocks() {
    $params = [
        'function' => 'LISTING_STATUS',
        'state' => 'active' // Only active stocks
    ];
    return call_finance_api($params);
}

function get_stock_overview($symbol) {
    $params = [
        'function' => 'OVERVIEW',
        'symbol' => $symbol
    ];
    return call_finance_api($params);
}

function get_stock_quote($symbol) {
    $params = [
        'function' => 'GLOBAL_QUOTE',
        'symbol' => $symbol
    ];
    return call_finance_api($params);
}

// Function to add a stock to the watchlist, now with data fetching
function add_stock_with_details($symbol, $pdo) {
    $overview = get_stock_overview($symbol);
    
    // Wait a bit before the next call to respect API limits
    sleep(15);

    $quote = get_stock_quote($symbol);

    if (isset($overview['error']) || isset($quote['error'])) {
        // Don't add to DB if API fails
        return ['success' => false, 'message' => ($overview['error'] ?? $quote['error'])];
    }

    if (empty($overview['Name']) || empty($overview['MarketCapitalization'])) {
         // If overview fails or is empty, we can't proceed.
        return ['success' => false, 'message' => 'Could not retrieve complete data for symbol.'];
    } else {
        $company_name = $overview['Name'];
        $price = isset($quote['Global Quote']['05. price']) ? (float)$quote['Global Quote']['05. price'] : 0;
        $change_percent_raw = isset($quote['Global Quote']['10. change percent']) ? $quote['Global Quote']['10. change percent'] : '0%';
        $change_percent = rtrim($change_percent_raw, '%');
    }

    $stmt = $pdo->prepare("INSERT INTO watchlist (symbol, company_name, price, change_percent) VALUES (?, ?, ?, ?)");
    $result = $stmt->execute([$symbol, $company_name, $price, $change_percent]);

    return ['success' => $result];
}