package compat

import (
	"encoding/json"
	"net"
	"net/http"
	"os"
	"strings"
	"syscall"
	"time"

	"github.com/containernetworking/cni/libcni"
	"github.com/containers/podman/v2/libpod"
	"github.com/containers/podman/v2/libpod/define"
	"github.com/containers/podman/v2/libpod/network"
	"github.com/containers/podman/v2/pkg/api/handlers/utils"
	"github.com/containers/podman/v2/pkg/domain/entities"
	"github.com/containers/podman/v2/pkg/domain/infra/abi"
	"github.com/docker/docker/api/types"
	dockerNetwork "github.com/docker/docker/api/types/network"
	"github.com/gorilla/schema"
	"github.com/pkg/errors"
	"github.com/sirupsen/logrus"
)

func InspectNetwork(w http.ResponseWriter, r *http.Request) {
	runtime := r.Context().Value("runtime").(*libpod.Runtime)

	// FYI scope and version are currently unused but are described by the API
	// Leaving this for if/when we have to enable these
	// query := struct {
	//	scope   string
	//	verbose bool
	// }{
	//	// override any golang type defaults
	// }
	// decoder := r.Context().Value("decoder").(*schema.Decoder)
	// if err := decoder.Decode(&query, r.URL.Query()); err != nil {
	//	utils.Error(w, "Something went wrong.", http.StatusBadRequest, errors.Wrapf(err, "failed to parse parameters for %s", r.URL.String()))
	//	return
	// }
	config, err := runtime.GetConfig()
	if err != nil {
		utils.InternalServerError(w, err)
		return
	}
	name := utils.GetName(r)
	_, err = network.InspectNetwork(config, name)
	if err != nil {
		utils.NetworkNotFound(w, name, err)
		return
	}
	report, err := getNetworkResourceByName(name, runtime)
	if err != nil {
		utils.InternalServerError(w, err)
		return
	}
	utils.WriteResponse(w, http.StatusOK, report)
}

func getNetworkResourceByName(name string, runtime *libpod.Runtime) (*types.NetworkResource, error) {
	var (
		ipamConfigs []dockerNetwork.IPAMConfig
	)
	config, err := runtime.GetConfig()
	if err != nil {
		return nil, err
	}
	containerEndpoints := map[string]types.EndpointResource{}
	// Get the network path so we can get created time
	networkConfigPath, err := network.GetCNIConfigPathByName(config, name)
	if err != nil {
		return nil, err
	}
	f, err := os.Stat(networkConfigPath)
	if err != nil {
		return nil, err
	}
	stat := f.Sys().(*syscall.Stat_t)
	cons, err := runtime.GetAllContainers()
	if err != nil {
		return nil, err
	}
	conf, err := libcni.ConfListFromFile(networkConfigPath)
	if err != nil {
		return nil, err
	}

	// No Bridge plugin means we bail
	bridge, err := genericPluginsToBridge(conf.Plugins, network.DefaultNetworkDriver)
	if err != nil {
		return nil, err
	}
	for _, outer := range bridge.IPAM.Ranges {
		for _, n := range outer {
			ipamConfig := dockerNetwork.IPAMConfig{
				Subnet:  n.Subnet,
				Gateway: n.Gateway,
			}
			ipamConfigs = append(ipamConfigs, ipamConfig)
		}
	}

	for _, con := range cons {
		data, err := con.Inspect(false)
		if err != nil {
			return nil, err
		}
		if netData, ok := data.NetworkSettings.Networks[name]; ok {
			containerEndpoint := types.EndpointResource{
				Name:        netData.NetworkID,
				EndpointID:  netData.EndpointID,
				MacAddress:  netData.MacAddress,
				IPv4Address: netData.IPAddress,
				IPv6Address: netData.GlobalIPv6Address,
			}
			containerEndpoints[con.ID()] = containerEndpoint
		}
	}
	report := types.NetworkResource{
		Name:       name,
		ID:         name,
		Created:    time.Unix(int64(stat.Ctim.Sec), int64(stat.Ctim.Nsec)), // nolint: unconvert
		Scope:      "",
		Driver:     network.DefaultNetworkDriver,
		EnableIPv6: false,
		IPAM: dockerNetwork.IPAM{
			Driver:  "default",
			Options: nil,
			Config:  ipamConfigs,
		},
		Internal:   false,
		Attachable: false,
		Ingress:    false,
		ConfigFrom: dockerNetwork.ConfigReference{},
		ConfigOnly: false,
		Containers: containerEndpoints,
		Options:    nil,
		Labels:     nil,
		Peers:      nil,
		Services:   nil,
	}
	return &report, nil
}

func genericPluginsToBridge(plugins []*libcni.NetworkConfig, pluginType string) (network.HostLocalBridge, error) {
	var bridge network.HostLocalBridge
	generic, err := findPluginByName(plugins, pluginType)
	if err != nil {
		return bridge, err
	}
	err = json.Unmarshal(generic, &bridge)
	return bridge, err
}

func findPluginByName(plugins []*libcni.NetworkConfig, pluginType string) ([]byte, error) {
	for _, p := range plugins {
		if pluginType == p.Network.Type {
			return p.Bytes, nil
		}
	}
	return nil, errors.New("unable to find bridge plugin")
}

func ListNetworks(w http.ResponseWriter, r *http.Request) {
	runtime := r.Context().Value("runtime").(*libpod.Runtime)
	decoder := r.Context().Value("decoder").(*schema.Decoder)
	query := struct {
		Filters map[string][]string `schema:"filters"`
	}{
		// override any golang type defaults
	}
	if err := decoder.Decode(&query, r.URL.Query()); err != nil {
		utils.Error(w, "Something went wrong.", http.StatusBadRequest, errors.Wrapf(err, "failed to parse parameters for %s", r.URL.String()))
		return
	}
	config, err := runtime.GetConfig()
	if err != nil {
		utils.InternalServerError(w, err)
		return
	}

	filterNames, nameFilterExists := query.Filters["name"]
	// TODO remove when filters are implemented
	if (!nameFilterExists && len(query.Filters) > 0) || len(query.Filters) > 1 {
		utils.InternalServerError(w, errors.New("only the name filter for listing networks is implemented"))
		return
	}
	netNames, err := network.GetNetworkNamesFromFileSystem(config)
	if err != nil {
		utils.InternalServerError(w, err)
		return
	}

	// filter by name
	if nameFilterExists {
		names := []string{}
		for _, name := range netNames {
			for _, filter := range filterNames {
				if strings.Contains(name, filter) {
					names = append(names, name)
					break
				}
			}
		}
		netNames = names
	}

	reports := make([]*types.NetworkResource, 0, len(netNames))
	logrus.Errorf("netNames: %q", strings.Join(netNames, ", "))
	for _, name := range netNames {
		report, err := getNetworkResourceByName(name, runtime)
		if err != nil {
			utils.InternalServerError(w, err)
			return
		}
		reports = append(reports, report)
	}
	utils.WriteResponse(w, http.StatusOK, reports)
}

func CreateNetwork(w http.ResponseWriter, r *http.Request) {
	var (
		name          string
		networkCreate types.NetworkCreateRequest
	)
	runtime := r.Context().Value("runtime").(*libpod.Runtime)
	if err := json.NewDecoder(r.Body).Decode(&networkCreate); err != nil {
		utils.Error(w, "Something went wrong.", http.StatusInternalServerError, errors.Wrap(err, "Decode()"))
		return
	}

	if len(networkCreate.Name) > 0 {
		name = networkCreate.Name
	}
	if len(networkCreate.Driver) < 1 {
		networkCreate.Driver = network.DefaultNetworkDriver
	}
	// At present I think we should just support the bridge driver
	// and allow demand to make us consider more
	if networkCreate.Driver != network.DefaultNetworkDriver {
		utils.InternalServerError(w, errors.New("network create only supports the bridge driver"))
		return
	}
	ncOptions := entities.NetworkCreateOptions{
		Driver:   network.DefaultNetworkDriver,
		Internal: networkCreate.Internal,
	}
	if networkCreate.IPAM != nil && networkCreate.IPAM.Config != nil {
		if len(networkCreate.IPAM.Config) > 1 {
			utils.InternalServerError(w, errors.New("compat network create can only support one IPAM config"))
			return
		}

		if len(networkCreate.IPAM.Config[0].Subnet) > 0 {
			_, subnet, err := net.ParseCIDR(networkCreate.IPAM.Config[0].Subnet)
			if err != nil {
				utils.InternalServerError(w, err)
				return
			}
			ncOptions.Subnet = *subnet
		}
		if len(networkCreate.IPAM.Config[0].Gateway) > 0 {
			ncOptions.Gateway = net.ParseIP(networkCreate.IPAM.Config[0].Gateway)
		}
		if len(networkCreate.IPAM.Config[0].IPRange) > 0 {
			_, IPRange, err := net.ParseCIDR(networkCreate.IPAM.Config[0].IPRange)
			if err != nil {
				utils.InternalServerError(w, err)
				return
			}
			ncOptions.Range = *IPRange
		}
	}
	ce := abi.ContainerEngine{Libpod: runtime}
	if _, err := ce.NetworkCreate(r.Context(), name, ncOptions); err != nil {
		utils.InternalServerError(w, err)
		return
	}

	body := struct {
		Id      string
		Warning []string
	}{
		Id: name,
	}
	utils.WriteResponse(w, http.StatusCreated, body)
}

func RemoveNetwork(w http.ResponseWriter, r *http.Request) {
	runtime := r.Context().Value("runtime").(*libpod.Runtime)
	ic := abi.ContainerEngine{Libpod: runtime}

	query := struct {
		Force bool `schema:"force"`
	}{
		// This is where you can override the golang default value for one of fields
	}

	decoder := r.Context().Value("decoder").(*schema.Decoder)
	if err := decoder.Decode(&query, r.URL.Query()); err != nil {
		utils.Error(w, "Something went wrong.", http.StatusBadRequest, errors.Wrapf(err, "failed to parse parameters for %s", r.URL.String()))
		return
	}

	options := entities.NetworkRmOptions{
		Force: query.Force,
	}

	name := utils.GetName(r)
	reports, err := ic.NetworkRm(r.Context(), []string{name}, options)
	if err != nil {
		utils.Error(w, "remove Network failed", http.StatusInternalServerError, err)
		return
	}
	if len(reports) == 0 {
		utils.Error(w, "remove Network failed", http.StatusInternalServerError, errors.Errorf("internal error"))
		return
	}
	report := reports[0]
	if report.Err != nil {
		if errors.Cause(report.Err) == define.ErrNoSuchNetwork {
			utils.Error(w, "network not found", http.StatusNotFound, define.ErrNoSuchNetwork)
			return
		}
		utils.InternalServerError(w, report.Err)
		return
	}

	utils.WriteResponse(w, http.StatusNoContent, "")
}

// Connect adds a container to a network
func Connect(w http.ResponseWriter, r *http.Request) {
	runtime := r.Context().Value("runtime").(*libpod.Runtime)

	var (
		aliases    []string
		netConnect types.NetworkConnect
	)
	if err := json.NewDecoder(r.Body).Decode(&netConnect); err != nil {
		utils.Error(w, "Something went wrong.", http.StatusInternalServerError, errors.Wrap(err, "Decode()"))
		return
	}
	name := utils.GetName(r)
	if netConnect.EndpointConfig != nil {
		if netConnect.EndpointConfig.Aliases != nil {
			aliases = netConnect.EndpointConfig.Aliases
		}
	}
	err := runtime.ConnectContainerToNetwork(netConnect.Container, name, aliases)
	if err != nil {
		if errors.Cause(err) == define.ErrNoSuchCtr {
			utils.ContainerNotFound(w, netConnect.Container, err)
			return
		}
		if errors.Cause(err) == define.ErrNoSuchNetwork {
			utils.Error(w, "network not found", http.StatusNotFound, err)
			return
		}
		utils.Error(w, "Something went wrong.", http.StatusInternalServerError, err)
		return
	}
	utils.WriteResponse(w, http.StatusOK, "OK")
}

// Disconnect removes a container from a network
func Disconnect(w http.ResponseWriter, r *http.Request) {
	runtime := r.Context().Value("runtime").(*libpod.Runtime)

	var netDisconnect types.NetworkDisconnect
	if err := json.NewDecoder(r.Body).Decode(&netDisconnect); err != nil {
		utils.Error(w, "Something went wrong.", http.StatusInternalServerError, errors.Wrap(err, "Decode()"))
		return
	}

	name := utils.GetName(r)
	err := runtime.DisconnectContainerFromNetwork(netDisconnect.Container, name, netDisconnect.Force)
	if err != nil {
		if errors.Cause(err) == define.ErrNoSuchCtr {
			utils.Error(w, "container not found", http.StatusNotFound, err)
			return
		}
		if errors.Cause(err) == define.ErrNoSuchNetwork {
			utils.Error(w, "network not found", http.StatusNotFound, err)
			return
		}
		utils.Error(w, "Something went wrong.", http.StatusInternalServerError, err)
		return
	}
	utils.WriteResponse(w, http.StatusOK, "OK")
}