<?php

require_once 'db.inc.php';
require_once 'funcs.inc.php';

global $pdo;

$action = $_POST['action'] ?? null;

switch($action) {
    case 'new-species':
        handle_new_species($_POST);
        break;

    case 'delete-species':
        handle_delete_species($_POST);
        break;

    case 'login':
        handle_login($_POST);
        break;

    default:
        die("Request not understood");
}

function handle_new_species($form_data) {
    global $pdo;

    // step 1 : validate
    // start optimistic
    $error_messages = [];
    $redirect_location = "index.php"; // where to go if succesful

    $required_fields = [
        'ScientificName' => "You must enter a scientific name",
        'ListingStatus' => "You must select a listing status",
        'SpeciesType'  => "You must select a species type",
        'RegionName' => "You must select a region name",
        'OrganizationName' => "You must select an organization name"
    ];

    foreach ($required_fields as $req_field => $err_msg) {
        // validate each required field
        if (!isset($form_data[$req_field]) || empty($form_data[$req_field])) {
            $error_messages[] = $err_msg;
        }
    }

    if (!empty($error_messages)) {
        // step 2a : if invalid, send back to form with errors & data
        $form_data['error_messages'] = $error_messages;
        extract(prepareNewSpeciesData($form_data));
        include 'speciesForm.html.php';

    }
    else {
        // step 2b : add new entry
        //Need to add RegionName from Region for Listed_In table
        //Need to add OrganizationName from Organization for Protected_By
        try {

            //$numSpecies = 0;

            $sql = 'INSERT INTO Species SET
                ScientificName = :ScientificName,
                CommonName = :CommonName,
                FWSLink = :FWSLink,
                ListingStatus = :ListingStatus,
                SpeciesType = :SpeciesType';

            $s = $pdo ->prepare($sql);

            $s->bindValue(':ScientificName',$_POST['ScientificName']);
            $s->bindValue(':CommonName',$_POST['CommonName']);
            $s->bindValue(':FWSLink',$_POST['FWSLink']);
            $s->bindValue(':ListingStatus',$_POST['ListingStatus']);
            $s->bindValue(':SpeciesType',$_POST['SpeciesType']);

            $s->execute();

            $sqlListed = 'INSERT INTO Listed_In SET
                ScientificName= :ScientificName,
                RegionName= :RegionName';

            $s = $pdo->prepare($sqlListed);

            $s->bindValue(':ScientificName',$_POST['ScientificName']);
            $s->bindValue(':RegionName',$_POST['RegionName']);

            $s->execute();


            $sqlProtected = 'INSERT INTO Protected_By SET
                ScientificName = :ScientificName,
                OrganizationName = :OrganizationName';

            $s = $pdo -> prepare($sqlProtected);

            $s->bindValue(':ScientificName',$_POST['ScientificName']);
            $s->bindValue(':OrganizationName',$_POST['OrganizationName']);

            $s->execute();

            header('Location: ' . $redirect_location);
        }
        catch(PDOException $e)
        {
            $error = 'Error adding species: ' .$e->getMessage();
            include 'error.html.php';
            exit();
        }
    }
}

function handle_delete_species($form_data) {
    global $pdo;

    $redirect_location = "index.php";
    try
    {
        $sql = 'DELETE FROM Species WHERE ScientificName = :id';
        $s = $pdo->prepare($sql);
        $s->bindValue(':id',$_POST['id']);

        $s->execute();

        header('Location: ' . $redirect_location);
    }
    catch(PDOException $e)
    {
        $error = 'Error deleting species: ' .$e->getMessage();
        include 'error.html.php';
        exit();
    }
}

function handle_login($form_data)
{
    global $pdo;

    $redirect_location = "index.php";

    session_start();
    //try to login

    $sql = 'INSERT INTO users SET
                username = :username,
                password = :password';

    $s = $pdo ->prepare($sql);

    $s->bindValue(':username',$_POST['username']);
    $s->bindValue(':password',$_POST['password']);

    $tablePrefix = "";
    $userTable = $tablePrefix . "users";

    $query = "SELECT * FROM {$userTable} WHERE username='{$_POST['username']}'";
    $result = $pdo->query($query);
    if( !$result ) {
    //an error occured
    die( "There was a problem executing the SQL query." );
    }

    if( !$result->rowCount()) {
    //no results found
    die( "This user does not exist." );
    }
    //get the user as an object
    $user = $result->fetchObject();

    //verify the passwords match
    $matches = password_verify( $_POST['password'], $user->password );
    if( !$matches )
    die( "Invalid password." );

    $_SESSION['user'] = $user;
    echo "<pre>"; var_dump($_SESSION);die();

    // // forces the user to log in before they view this page
    if (! isset($_SESSION['user'])) die("you must log in");

    header('Location: ' . $redirect_location);
}

function handle_change_status($form_data)
{
    global $pdo;
    try
    {
        $scientificName = $_POST['ScientificName'];
        $status = $_POST['ListingStatus'];

        $sql = "UPDATE Species SET ListingStatus = '$status' WHERE ScientificName = '$scientificName'";
        $result = $pdo->query($sql);
        $result -> execute();

        header('Location: ' . $redirect_location);
    }
    catch(PDOException $e)
    {
        $error = 'Error changing listing status: ' .$e->getMessage();
        include 'error.html.php';
        exit();
    }
}