package PVE::HTTPServer;

use strict;
use warnings;

use PVE::SafeSyslog;
use PVE::INotify;
use PVE::Tools;
use PVE::APIServer::AnyEvent;
use PVE::Exception qw(raise_param_exc raise_perm_exc raise);

use PVE::RPCEnvironment;
use PVE::AccessControl;
use PVE::CertCache;
use PVE::Cluster;
use PVE::API2Tools;

use Data::Dumper;

use base('PVE::APIServer::AnyEvent');

use HTTP::Status qw(:constants);

sub new {
    my ($this, %args) = @_;

    my $class = ref($this) || $this;
    my $self = $class->SUPER::new(%args);

    $self->{rpcenv} = PVE::RPCEnvironment->init(
	$self->{trusted_env} ? 'priv' : 'pub',
	atfork => sub { $self->atfork_handler() },
    );

    return $self;
}

sub verify_spice_connect_url {
    my ($self, $connect_str) = @_;

    my $rpcenv = $self->{rpcenv};
    $rpcenv->init_request();

    my ($vmid, $node, $port) = PVE::AccessControl::verify_spice_connect_url($connect_str);

    return ($vmid, $node, $port);
}

sub generate_csrf_prevention_token {
    my ($username) = @_;
    return PVE::AccessControl::assemble_csrf_prevention_token($username);
}

sub auth_handler {
    my ($self, $method, $rel_uri, $ticket, $token, $api_token, $peer_host) = @_;

    my $rpcenv = $self->{rpcenv};

    # set environment variables
    $rpcenv->set_user(undef);
    $rpcenv->set_language('C');
    $rpcenv->set_client_ip($peer_host);

    eval { $rpcenv->init_request() };
    raise("RPCEnvironment init request failed: $@\n") if $@;

    my $require_auth = 1;

    # explicitly allow some calls without auth
    if (($rel_uri eq '/access/domains' && $method eq 'GET') ||
	($rel_uri eq '/access/ticket' && ($method eq 'GET' || $method eq 'POST'))) {
	$require_auth = 0;
    }

    my ($username, $age);

    my $isUpload = 0;

    if ($require_auth) {
	if ($api_token) {
	    # the token-ID `<user>@<realm>!<tokenname>` is the user for token based authentication
	    $username = PVE::AccessControl::verify_token($api_token);
	} else {
	    die "No ticket\n" if !$ticket;

	    ($username, $age, my $tfa_info) = PVE::AccessControl::verify_ticket($ticket);
	    $rpcenv->check_user_enabled($username);

	    if (defined($tfa_info)) {
		if (defined(my $challenge = $tfa_info->{challenge})) {
		    $rpcenv->set_u2f_challenge($challenge);
		}
		die "No ticket\n" if ($rel_uri ne '/access/tfa' || $method ne 'POST');
	    }
	}

	$rpcenv->set_user($username);

	if ($method eq 'POST' && $rel_uri =~ m|^/nodes/([^/]+)/storage/([^/]+)/upload$|) {
	    my ($node, $storeid) = ($1, $2);
	    # CSRF check are omitted if $isUpload is set, so check user upload permission here
	    my $perm = { check => ['perm', "/storage/$storeid", ['Datastore.AllocateTemplate']] };
	    $rpcenv->check_api2_permissions($perm, $username, {});
	    $isUpload = 1;
	}

	# Skip CSRF check for file upload (difficult to pass CSRF header with native html forms).
	# Also skip the check with API tokens, as one of the design goals of API tokens was to
	# provide stateless API access without requiring round-trips to get such CSRF tokens.
	# CSRF-prevention also does not make much sense outside of the browser context.
	if ($method ne 'GET' && !($api_token || $isUpload)) {
	    my $euid = $>;
	    PVE::AccessControl::verify_csrf_prevention_token($username, $token) if $euid != 0;
	}
    }

    return {
	ticket => $ticket,
	token => $token,
	userid => $username,
	age => $age,
	isUpload => $isUpload,
	api_token => $api_token,
    };
}

sub rest_handler {
    my ($self, $clientip, $method, $rel_uri, $auth, $params) = @_;

    my $rpcenv = $self->{rpcenv};

    my $resp = {
	status => HTTP_NOT_IMPLEMENTED,
	message => "Method '$method $rel_uri' not implemented",
    };

    my ($handler, $info);

    eval {
	my $uri_param = {};
	($handler, $info) = PVE::API2->find_handler($method, $rel_uri, $uri_param);
	return if !$handler || !$info;

	for my $p (sort keys %{$params}) {
	    if (defined($uri_param->{$p}) && $uri_param->{$p} ne $params->{$p}) {
		raise_param_exc({
		    $p => "duplicate parameter (already defined in URI) with conflicting values!"
		});
	    }
	    $uri_param->{$p} = $params->{$p};
	}

	raise_perm_exc("URI '$rel_uri' not available with API token, need proper ticket.\n")
	    if $auth->{api_token} && !$info->{allowtoken};

	# check access permissions
	$rpcenv->check_api2_permissions($info->{permissions}, $auth->{userid}, $uri_param);

	if ($info->{proxyto} || $info->{proxyto_callback}) {
	    my $node = PVE::API2Tools::resolve_proxyto(
		$rpcenv, $info->{proxyto_callback}, $info->{proxyto}, $uri_param);

	    if ($node ne 'localhost' && $node ne PVE::INotify::nodename()) {
		die "unable to proxy file uploads" if $auth->{isUpload};
		my $remip = $self->remote_node_ip($node);
		$resp = { proxy => $remip, proxynode => $node, proxy_params => $params };
		return;
	    }
	}

	my $euid = $>;
	if ($info->{protected} && ($euid != 0)) {
	    $resp = { proxy => 'localhost' , proxy_params => $params };
	    return;
	}

	$resp = {
	    data => $handler->handle($info, $uri_param),
	    info => $info, # useful to format output
	    status => HTTP_OK,
	};

	if (my $count = $rpcenv->get_result_attrib('total')) {
	    $resp->{total} = $count;
	}

	if (my $diff = $rpcenv->get_result_attrib('changes')) {
	    $resp->{changes} = $diff;
	}
    };
    my $err = $@;

    $rpcenv->set_user(undef); # clear after request

    if ($err) {
	$resp = { info => $info };
	if (ref($err) eq "PVE::Exception") {
	    $resp->{status} = $err->{code} || HTTP_INTERNAL_SERVER_ERROR;
	    $resp->{errors} = $err->{errors} if $err->{errors};
	    $resp->{message} = $err->{msg};
	} else {
	    $resp->{status} =  HTTP_INTERNAL_SERVER_ERROR;
	    $resp->{message} = $err;
	}
    }

    return $resp;
}

sub check_cert_fingerprint {
    my ($self, $cert) = @_;
    return PVE::CertCache::check_cert_fingerprint($cert);
}

sub initialize_cert_cache {
    my ($self, $node) = @_;
    PVE::CertCache::initialize_cert_cache($node);
}

sub remote_node_ip {
    my ($self, $node) = @_;

    my $remip = PVE::Cluster::remote_node_ip($node);
    die "unable to get remote IP address for node '$node'\n" if !$remip;

    return $remip;
}

1;
