<?php
require_once __DIR__ . "/session_bootstrap.php";

$client_id = "YOUR-EVE-CLIENT-ID";
// Replace with your ESI client secret from EVE Developer Portal
$client_secret = "YOUR-EVE-CLIENT-SECRET";
$redirect_uri = "YOUR-CALLBACK-URL"; // Example: https://your-domain.com/callback.php

// Validate the OAuth state and code
if (
    !isset($_GET["code"]) ||
    !isset($_GET["state"]) ||
    $_GET["state"] !== $_SESSION["oauth2state"]
) {
    exit("Invalid state or code");
}

$code = $_GET["code"];
$token_url = "https://login.eveonline.com/v2/oauth/token";

// Get the access and refresh tokens
$ch = curl_init($token_url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt(
    $ch,
    CURLOPT_POSTFIELDS,
    http_build_query([
        "grant_type" => "authorization_code",
        "code" => $code,
        "redirect_uri" => $redirect_uri,
    ])
);
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    "Authorization: Basic " . base64_encode($client_id . ":" . $client_secret),
    "Content-Type: application/x-www-form-urlencoded",
]);

$response = curl_exec($ch);
$http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
curl_close($ch);

$token_data = json_decode($response, true);

// Fail gracefully if token fetch fails
if (!is_array($token_data) || !isset($token_data["access_token"])) {
    error_log("Token exchange failed: $response");
    exit("Failed to retrieve access token");
}

// Use access token to get character info
$ch = curl_init("https://login.eveonline.com/oauth/verify");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    "Authorization: Bearer " . $token_data["access_token"],
]);
$user_data = json_decode(curl_exec($ch), true);
curl_close($ch);

// Validate user info
if (!is_array($user_data) || !isset($user_data["CharacterID"])) {
    error_log("Failed to verify character: " . json_encode($user_data));
    exit("Character verification failed");
}

$character_id = $user_data["CharacterID"];
$character_name = $user_data["CharacterName"];

// Save access & refresh tokens in session
if (!isset($_SESSION["characters"][$character_id])) {
    $_SESSION["characters"][$character_id] = [
        "name" => $character_name,
        "access_token" => $token_data["access_token"],
        "refresh_token" => $token_data["refresh_token"] ?? null,
    ];
} else {
    error_log("Character data already exists for ID: $character_id. Skipping overwrite.");
}

// Redirect back to main page
header("Location: index.php");
exit();