// Package osl describes structures and interfaces which abstract os entities
package osl

import (
	"net"

	"github.com/docker/docker/libnetwork/types"
)

// SandboxType specify the time of the sandbox, this can be used to apply special configs
type SandboxType int

const (
	// SandboxTypeIngress indicates that the sandbox is for the ingress
	SandboxTypeIngress = iota
	// SandboxTypeLoadBalancer indicates that the sandbox is a load balancer
	SandboxTypeLoadBalancer = iota
)

// IfaceOption is a function option type to set interface options.
type IfaceOption func(i *nwIface)

// NeighOption is a function option type to set neighbor options.
type NeighOption func(nh *neigh)

// Sandbox represents a network sandbox, identified by a specific key.  It
// holds a list of Interfaces, routes etc, and more can be added dynamically.
type Sandbox interface {
	// Key returns the path where the network namespace is mounted.
	Key() string

	// AddInterface adds an existing Interface to this sandbox. The operation will rename
	// from the Interface SrcName to DstName as it moves, and reconfigure the
	// interface according to the specified settings. The caller is expected
	// to only provide a prefix for DstName. The AddInterface api will auto-generate
	// an appropriate suffix for the DstName to disambiguate.
	AddInterface(SrcName string, DstPrefix string, options ...IfaceOption) error

	// SetGateway sets the default IPv4 gateway for the sandbox.
	SetGateway(gw net.IP) error

	// SetGatewayIPv6 sets the default IPv6 gateway for the sandbox.
	SetGatewayIPv6(gw net.IP) error

	// UnsetGateway the previously set default IPv4 gateway in the sandbox.
	UnsetGateway() error

	// UnsetGatewayIPv6 unsets the previously set default IPv6 gateway in the sandbox.
	UnsetGatewayIPv6() error

	// GetLoopbackIfaceName returns the name of the loopback interface
	GetLoopbackIfaceName() string

	// AddAliasIP adds the passed IP address to the named interface
	AddAliasIP(ifName string, ip *net.IPNet) error

	// RemoveAliasIP removes the passed IP address from the named interface
	RemoveAliasIP(ifName string, ip *net.IPNet) error

	// DisableARPForVIP disables ARP replies and requests for VIP addresses
	// on a particular interface.
	DisableARPForVIP(ifName string) error

	// AddStaticRoute adds a static route to the sandbox.
	AddStaticRoute(*types.StaticRoute) error

	// RemoveStaticRoute removes a static route from the sandbox.
	RemoveStaticRoute(*types.StaticRoute) error

	// AddNeighbor adds a neighbor entry into the sandbox.
	AddNeighbor(dstIP net.IP, dstMac net.HardwareAddr, force bool, option ...NeighOption) error

	// DeleteNeighbor deletes neighbor entry from the sandbox.
	DeleteNeighbor(dstIP net.IP, dstMac net.HardwareAddr, osDelete bool) error

	// NeighborOptions returns an interface with methods to set neighbor options.
	NeighborOptions() NeighborOptionSetter

	// InterfaceOptions an interface with methods to set interface options.
	InterfaceOptions() IfaceOptionSetter

	// InvokeFunc invoke a function in the network namespace.
	InvokeFunc(func()) error

	// Info returns an interface with methods to get sandbox state.
	Info() Info

	// Destroy destroys the sandbox.
	Destroy() error

	// Restore restores the sandbox.
	Restore(ifsopt map[string][]IfaceOption, routes []*types.StaticRoute, gw net.IP, gw6 net.IP) error

	// ApplyOSTweaks applies operating system specific knobs on the sandbox.
	ApplyOSTweaks([]SandboxType)
}

// NeighborOptionSetter interface defines the option setter methods for interface options
type NeighborOptionSetter interface {
	// LinkName returns an option setter to set the srcName of the link that should
	// be used in the neighbor entry
	LinkName(string) NeighOption

	// Family returns an option setter to set the address family for the neighbor
	// entry. eg. AF_BRIDGE
	Family(int) NeighOption
}

// IfaceOptionSetter interface defines the option setter methods for interface options.
type IfaceOptionSetter interface {
	// Bridge returns an option setter to set if the interface is a bridge.
	Bridge(bool) IfaceOption

	// MacAddress returns an option setter to set the MAC address.
	MacAddress(net.HardwareAddr) IfaceOption

	// Address returns an option setter to set IPv4 address.
	Address(*net.IPNet) IfaceOption

	// AddressIPv6 returns an option setter to set IPv6 address.
	AddressIPv6(*net.IPNet) IfaceOption

	// LinkLocalAddresses returns an option setter to set the link-local IP addresses.
	LinkLocalAddresses([]*net.IPNet) IfaceOption

	// Master returns an option setter to set the master interface if any for this
	// interface. The master interface name should refer to the srcname of a
	// previously added interface of type bridge.
	Master(string) IfaceOption

	// Routes returns an option setter to set interface routes.
	Routes([]*net.IPNet) IfaceOption
}

// Info represents all possible information that
// the driver wants to place in the sandbox which includes
// interfaces, routes and gateway
type Info interface {
	// Interfaces returns the collection of Interface previously added with the AddInterface
	// method. Note that this doesn't include network interfaces added in any
	// other way (such as the default loopback interface which is automatically
	// created on creation of a sandbox).
	Interfaces() []Interface

	// Gateway returns the IPv4 gateway for the sandbox.
	Gateway() net.IP

	// GatewayIPv6 returns the IPv6 gateway for the sandbox.
	GatewayIPv6() net.IP

	// StaticRoutes returns additional static routes for the sandbox. Note that
	// directly connected routes are stored on the particular interface they
	// refer to.
	StaticRoutes() []*types.StaticRoute

	// TODO: Add ip tables etc.
}

// Interface represents the settings and identity of a network device. It is
// used as a return type for Network.Link, and it is common practice for the
// caller to use this information when moving interface SrcName from host
// namespace to DstName in a different net namespace with the appropriate
// network settings.
type Interface interface {
	// SrcName returns the name of the interface in the origin network namespace.
	SrcName() string

	// DstName returns the name that will be assigned to the interface once
	// moved inside a network namespace. When the caller passes in a DstName,
	// it is only expected to pass a prefix. The name will be modified with an
	// auto-generated suffix.
	DstName() string

	// Address returns the IPv4 address for the interface.
	Address() *net.IPNet

	// AddressIPv6 returns the IPv6 address for the interface.
	AddressIPv6() *net.IPNet

	// LinkLocalAddresses returns the link-local IP addresses assigned to the
	// interface.
	LinkLocalAddresses() []*net.IPNet

	// Routes returns IP routes for the interface.
	Routes() []*net.IPNet

	// Bridge returns true if the interface is a bridge.
	Bridge() bool

	// Master returns the srcname of the master interface for this interface.
	Master() string

	// Remove an interface from the sandbox by renaming to original name
	// and moving it out of the sandbox.
	Remove() error

	// Statistics returns the statistics for this interface
	Statistics() (*types.InterfaceStatistics, error)
}