package agenttokens

import (
	"flag"
	"fmt"
	"io"

	"github.com/hashicorp/consul/command/flags"
	"github.com/hashicorp/consul/command/helpers"
	"github.com/mitchellh/cli"
)

func New(ui cli.Ui) *cmd {
	c := &cmd{UI: ui}
	c.init()
	return c
}

type cmd struct {
	UI    cli.Ui
	flags *flag.FlagSet
	http  *flags.HTTPFlags
	help  string

	testStdin io.Reader
}

func (c *cmd) init() {
	c.flags = flag.NewFlagSet("", flag.ContinueOnError)
	c.http = &flags.HTTPFlags{}
	flags.Merge(c.flags, c.http.ClientFlags())
	flags.Merge(c.flags, c.http.ServerFlags())
	c.help = flags.Usage(help, c.flags)
}
func (c *cmd) Run(args []string) int {
	if err := c.flags.Parse(args); err != nil {
		return 1
	}

	tokenType, token, err := c.dataFromArgs(c.flags.Args())
	if err != nil {
		c.UI.Error(fmt.Sprintf("Error! %s", err))
		return 1
	}

	client, err := c.http.APIClient()
	if err != nil {
		c.UI.Error(fmt.Sprintf("Error connecting to Consul Agent: %s", err))
		return 1
	}

	switch tokenType {
	case "default":
		_, err = client.Agent().UpdateDefaultACLToken(token, nil)
	case "agent":
		_, err = client.Agent().UpdateAgentACLToken(token, nil)
	case "master":
		_, err = client.Agent().UpdateAgentMasterACLToken(token, nil)
	case "replication":
		_, err = client.Agent().UpdateReplicationACLToken(token, nil)
	default:
		c.UI.Error(fmt.Sprintf("Unknown token type"))
		return 1
	}

	if err != nil {
		c.UI.Error(fmt.Sprintf("Failed to set ACL token %q: %v", tokenType, err))
		return 1
	}

	c.UI.Info(fmt.Sprintf("ACL token %q set successfully", tokenType))
	return 0
}

func (c *cmd) dataFromArgs(args []string) (string, string, error) {
	switch len(args) {
	case 0:
		return "", "", fmt.Errorf("Missing TYPE and TOKEN arguments")
	case 1:
		switch args[0] {
		case "default", "agent", "master", "replication":
			return "", "", fmt.Errorf("Missing TOKEN argument")
		default:
			return "", "", fmt.Errorf("MISSING TYPE argument")
		}
	case 2:
		data, err := helpers.LoadDataSource(args[1], c.testStdin)
		if err != nil {
			return "", "", err
		}

		return args[0], data, nil
	default:
		return "", "", fmt.Errorf("Too many arguments: expected 2 got %d", len(args))
	}
}

func (c *cmd) Synopsis() string {
	return synopsis
}

func (c *cmd) Help() string {
	return flags.Usage(c.help, nil)
}

const synopsis = "Assign tokens for the Consul Agent's usage"
const help = `
Usage: consul acl set-agent-token [options] TYPE TOKEN

  This command will set the corresponding token for the agent to use.
  Note that the tokens uploaded this way are not persisted and if
  the agent reloads then the tokens will need to be set again.

  Token Types:

    default       The default token is the token that the agent will use for
                  both internal agent operations and operations initiated by
                  the HTTP and DNS interfaces when no specific token is provided.
                  If not set the agent will use the anonymous token.

    agent         The token that the agent will use for internal agent operations.
                  If not given then the default token is used for these operations.

    master        This sets the token that can be used to access the Agent APIs in
                  the event that the ACL datacenter cannot be reached.

    replication   This is the token that the agent will use for replication
                  operations. This token will need to be configured with read access
                  to whatever data is being replicated.

  Example:

    $ consul acl set-agent-token default c4d0f8df-3aba-4ab6-a7a0-35b760dc29a1
`