// Package cmd defines the command line flags for the shared utilities.
package cmd

import (
	"fmt"
	"math"
	"strings"

	"github.com/urfave/cli/v2"
	"github.com/urfave/cli/v2/altsrc"
)

var (
	// MinimalConfigFlag declares to use the minimal config for running Ethereum consensus.
	MinimalConfigFlag = &cli.BoolFlag{
		Name:  "minimal-config",
		Usage: "Uses minimal config with parameters as defined in the spec.",
	}
	// E2EConfigFlag declares to use a testing specific config for running Ethereum consensus in end-to-end testing.
	E2EConfigFlag = &cli.BoolFlag{
		Name:  "e2e-config",
		Usage: "Enables the E2E testing config, only for use within end-to-end testing.",
	}
	// RPCMaxPageSizeFlag defines the maximum numbers per page returned in RPC responses from this
	// beacon node (default: 500).
	RPCMaxPageSizeFlag = &cli.IntFlag{
		Name:  "rpc-max-page-size",
		Usage: "Max number of items returned per page in RPC responses for paginated endpoints.",
	}
	// VerbosityFlag defines the logrus configuration.
	VerbosityFlag = &cli.StringFlag{
		Name:  "verbosity",
		Usage: "Logging verbosity. (trace, debug, info, warn, error, fatal, panic)",
		Value: "info",
	}
	// DataDirFlag defines a path on disk where Prysm databases are stored.
	DataDirFlag = &cli.StringFlag{
		Name:  "datadir",
		Usage: "Data directory for the databases.",
		Value: DefaultDataDir(),
	}
	// EnableBackupWebhookFlag for users to trigger db backups via an HTTP webhook.
	EnableBackupWebhookFlag = &cli.BoolFlag{
		Name: "enable-db-backup-webhook",
		Usage: `Serves HTTP handler to initiate database backups.
		The handler is served on the monitoring port at path /db/backup.`,
	}
	// BackupWebhookOutputDir to customize the output directory for db backups.
	BackupWebhookOutputDir = &cli.StringFlag{
		Name:  "db-backup-output-dir",
		Usage: "Output directory for db backups.",
	}
	// EnableTracingFlag defines a flag to enable p2p message tracing.
	EnableTracingFlag = &cli.BoolFlag{
		Name:  "enable-tracing",
		Usage: "Enables request tracing.",
	}
	// TracingProcessNameFlag defines a flag to specify a process name.
	TracingProcessNameFlag = &cli.StringFlag{
		Name:  "tracing-process-name",
		Usage: "Name to apply to tracing tag `process_name`.",
	}
	// TracingEndpointFlag flag defines the http endpoint for serving traces to Jaeger.
	TracingEndpointFlag = &cli.StringFlag{
		Name:  "tracing-endpoint",
		Usage: "Tracing endpoint defines where beacon chain traces are exposed to Jaeger.",
		Value: "http://127.0.0.1:14268/api/traces",
	}
	// TraceSampleFractionFlag defines a flag to indicate what fraction of p2p
	// messages are sampled for tracing.
	TraceSampleFractionFlag = &cli.Float64Flag{
		Name:  "trace-sample-fraction",
		Usage: "Indicates what fraction of p2p messages are sampled for tracing.",
		Value: 0.20,
	}
	// MonitoringHostFlag defines the host used to serve prometheus metrics.
	MonitoringHostFlag = &cli.StringFlag{
		Name:  "monitoring-host",
		Usage: "Host used for listening and responding metrics for prometheus.",
		Value: "127.0.0.1",
	}
	// DisableMonitoringFlag defines a flag to disable the metrics collection.
	DisableMonitoringFlag = &cli.BoolFlag{
		Name:  "disable-monitoring",
		Usage: "Disables monitoring service.",
	}
	// NoDiscovery specifies whether we are running a local network and have no need for connecting
	// to the bootstrap nodes in the cloud
	NoDiscovery = &cli.BoolFlag{
		Name:  "no-discovery",
		Usage: "Enable only local network p2p and do not connect to cloud bootstrap nodes",
	}
	// StaticPeers specifies a set of peers to connect to explicitly.
	StaticPeers = &cli.StringSliceFlag{
		Name:  "peer",
		Usage: "Connect with this peer, this flag may be used multiple times. This peer is recognized as a trusted peer.",
	}
	// BootstrapNode tells the beacon node which bootstrap node to connect to
	BootstrapNode = &cli.StringSliceFlag{
		Name:  "bootstrap-node",
		Usage: "The address of bootstrap node. Beacon node will connect for peer discovery via DHT.  Multiple nodes can be passed by using the flag multiple times but not comma-separated. You can also pass YAML files containing multiple nodes.",
	}
	// RelayNode tells the beacon node which relay node to connect to.
	RelayNode = &cli.StringFlag{
		Name: "relay-node",
		Usage: "The address of relay node. The beacon node will connect to the " +
			"relay node and advertise their address via the relay node to other peers",
		Value: "",
	}
	// P2PUDPPort defines the port to be used by discv5.
	P2PUDPPort = &cli.IntFlag{
		Name:  "p2p-udp-port",
		Usage: "The port used by discv5.",
		Value: 12000,
	}
	// P2PTCPPort defines the port to be used by libp2p.
	P2PTCPPort = &cli.IntFlag{
		Name:  "p2p-tcp-port",
		Usage: "The port used by libp2p.",
		Value: 13000,
	}
	// P2PIP defines the local IP to be used by libp2p.
	P2PIP = &cli.StringFlag{
		Name:  "p2p-local-ip",
		Usage: "The local ip address to listen for incoming data.",
		Value: "",
	}
	// P2PHost defines the host IP to be used by libp2p.
	P2PHost = &cli.StringFlag{
		Name:  "p2p-host-ip",
		Usage: "The IP address advertised by libp2p. This may be used to advertise an external IP.",
		Value: "",
	}
	// P2PHostDNS defines the host DNS to be used by libp2p.
	P2PHostDNS = &cli.StringFlag{
		Name:  "p2p-host-dns",
		Usage: "The DNS address advertised by libp2p. This may be used to advertise an external DNS.",
		Value: "",
	}
	// P2PPrivKey defines a flag to specify the location of the private key file for libp2p.
	P2PPrivKey = &cli.StringFlag{
		Name:  "p2p-priv-key",
		Usage: "The file containing the private key to use in communications with other peers.",
		Value: "",
	}
	P2PStaticID = &cli.BoolFlag{
		Name:  "p2p-static-id",
		Usage: "Enables the peer id of the node to be fixed by saving the generated network key to the default key path.",
		Value: false,
	}
	// P2PMetadata defines a flag to specify the location of the peer metadata file.
	P2PMetadata = &cli.StringFlag{
		Name:  "p2p-metadata",
		Usage: "The file containing the metadata to communicate with other peers.",
		Value: "",
	}
	// P2PMaxPeers defines a flag to specify the max number of peers in libp2p.
	P2PMaxPeers = &cli.IntFlag{
		Name:  "p2p-max-peers",
		Usage: "The max number of p2p peers to maintain.",
		Value: 70,
	}
	// P2PAllowList defines a CIDR subnet to exclusively allow connections.
	P2PAllowList = &cli.StringFlag{
		Name: "p2p-allowlist",
		Usage: "The CIDR subnet for allowing only certain peer connections. " +
			"Using \"public\" would allow only public subnets. Example: " +
			"192.168.0.0/16 would permit connections to peers on your local network only. The " +
			"default is to accept all connections.",
	}
	// P2PDenyList defines a list of CIDR subnets to disallow connections from them.
	P2PDenyList = &cli.StringSliceFlag{
		Name: "p2p-denylist",
		Usage: "The CIDR subnets for denying certainty peer connections. " +
			"Using \"private\" would deny all private subnets. Example: " +
			"192.168.0.0/16 would deny connections from peers on your local network only. The " +
			"default is to accept all connections.",
	}
	PubsubQueueSize = &cli.IntFlag{
		Name:  "pubsub-queue-size",
		Usage: "The size of the pubsub validation and outbound queue for the node.",
		Value: 1000,
	}
	// ForceClearDB removes any previously stored data at the data directory.
	ForceClearDB = &cli.BoolFlag{
		Name:  "force-clear-db",
		Usage: "Clears any previously stored data at the data directory.",
	}
	// ClearDB prompts user to see if they want to remove any previously stored data at the data directory.
	ClearDB = &cli.BoolFlag{
		Name:  "clear-db",
		Usage: "Prompt for clearing any previously stored data at the data directory.",
	}
	// LogFormat specifies the log output format.
	LogFormat = &cli.StringFlag{
		Name:  "log-format",
		Usage: "Specifies log formatting. Supports: text, json, fluentd, journald.",
		Value: "text",
	}
	// MaxGoroutines specifies the maximum amount of goroutines tolerated, before a status check fails.
	MaxGoroutines = &cli.IntFlag{
		Name:  "max-goroutines",
		Usage: "Specifies the upper limit of goroutines running before a status check fails",
		Value: 5000,
	}
	// LogFileName specifies the log output file name.
	LogFileName = &cli.StringFlag{
		Name:  "log-file",
		Usage: "Specifies log file name, relative or absolute.",
	}
	// EnableUPnPFlag specifies if UPnP should be enabled or not. The default value is false.
	EnableUPnPFlag = &cli.BoolFlag{
		Name:  "enable-upnp",
		Usage: "Enable the service (Beacon chain or Validator) to use UPnP when possible.",
	}
	// ConfigFileFlag specifies the filepath to load flag values.
	ConfigFileFlag = &cli.StringFlag{
		Name:  "config-file",
		Usage: "Filepath to a yaml file with flag values.",
	}
	// ChainConfigFileFlag specifies the filepath to load flag values.
	ChainConfigFileFlag = &cli.StringFlag{
		Name:  "chain-config-file",
		Usage: "Path to a YAML file with chain config values.",
	}
	// GrpcMaxCallRecvMsgSizeFlag defines the max call message size for GRPC
	GrpcMaxCallRecvMsgSizeFlag = &cli.IntFlag{
		Name: "grpc-max-msg-size",
		Usage: `Integer to define max receive message call size (in bytes).
		If serving a public gRPC server, set this to a more reasonable size to avoid
		resource exhaustion from large messages. 
		Validators with as many as 10000 keys can be run with a max message size of less than 
		50Mb. The default here is set to a very high value for local users.`,
		Value: math.MaxInt32,
	}
	// ValidatorMonitorIndicesFlag specifies a list of validator indices to
	// track for performance updates
	ValidatorMonitorIndicesFlag = &cli.IntSliceFlag{
		Name:  "monitor-indices",
		Usage: "List of validator indices to track performance",
	}

	// RestoreSourceFileFlag specifies the filepath to the backed-up database file
	// which will be used to restore the database.
	RestoreSourceFileFlag = &cli.StringFlag{
		Name:  "restore-source-file",
		Usage: "Filepath to the backed-up database file which will be used to restore the database",
	}
	// RestoreTargetDirFlag specifies the target directory of the restored database.
	RestoreTargetDirFlag = &cli.StringFlag{
		Name:  "restore-target-dir",
		Usage: "Target directory of the restored database",
		Value: DefaultDataDir(),
	}
	// ApiTimeoutFlag specifies the timeout value for API requests in seconds. A timeout of zero means no timeout.
	ApiTimeoutFlag = &cli.IntFlag{
		Name:  "api-timeout",
		Usage: "Specifies the timeout value for API requests in seconds.",
		Value: 120,
	}
	// JwtOutputFileFlag specifies the JWT file path that gets generated into when invoked by generate-jwt-secret.
	JwtOutputFileFlag = &cli.StringFlag{
		Name:    "output-file",
		Usage:   "Target file path for outputting a generated JWT secret to be used for JSON-RPC authentication",
		Aliases: []string{"o"},
	}
)

// LoadFlagsFromConfig sets flags values from config file if ConfigFileFlag is set.
func LoadFlagsFromConfig(cliCtx *cli.Context, flags []cli.Flag) error {
	if cliCtx.IsSet(ConfigFileFlag.Name) {
		if err := altsrc.InitInputSourceWithContext(flags, altsrc.NewYamlSourceFromFlagFunc(ConfigFileFlag.Name))(cliCtx); err != nil {
			return err
		}
	}
	return nil
}

// ValidateNoArgs insures that the application is not run with erroneous arguments or flags.
// This function should be used in the app.Before, whenever the application supports a default command.
func ValidateNoArgs(ctx *cli.Context) error {
	commandList := ctx.App.Commands
	parentCommand := ctx.Command
	isParamForFlag := false
	for _, a := range ctx.Args().Slice() {
		// We don't validate further if
		// the following value is actually
		// a parameter for a flag.
		if isParamForFlag {
			isParamForFlag = false
			continue
		}
		if strings.HasPrefix(a, "-") || strings.HasPrefix(a, "--") {
			// In the event our flag doesn't specify
			// the relevant argument with an equal
			// sign, we can assume the next argument
			// is the relevant value for the flag.
			flagName := strings.TrimPrefix(a, "--")
			flagName = strings.TrimPrefix(flagName, "-")
			if !strings.Contains(a, "=") && !isBoolFlag(parentCommand, flagName) {
				isParamForFlag = true
			}
			continue
		}
		c := checkCommandList(commandList, a)
		if c == nil {
			return fmt.Errorf("unrecognized argument: %s", a)
		}
		// Set the command list as the subcommand's
		// from the current selected parent command.
		commandList = c.Subcommands
		parentCommand = c
	}
	return nil
}

// verifies that the provided command is in the command list.
func checkCommandList(commands []*cli.Command, name string) *cli.Command {
	for _, c := range commands {
		if c.Name == name {
			return c
		}
	}
	return nil
}

func isBoolFlag(com *cli.Command, name string) bool {
	for _, f := range com.Flags {
		switch bFlag := f.(type) {
		case *cli.BoolFlag:
			if bFlag.Name == name {
				return true
			}
		case *altsrc.BoolFlag:
			if bFlag.Name == name {
				return true
			}
		}
	}
	return false
}