ec2.go

package main

import (
	"context"
	"fmt"
	"os"
	"text/tabwriter"

	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/service/ec2"
	ec2types "github.com/aws/aws-sdk-go-v2/service/ec2/types"
)

// nameTag returns the value of the "Name" tag, or "" if absent.
func nameTag(tags []ec2types.Tag) string {
	for _, t := range tags {
		if aws.ToString(t.Key) == "Name" {
			return aws.ToString(t.Value)
		}
	}
	return ""
}

func dash(s string) string {
	if s == "" {
		return "-"
	}
	return s
}

// cmdVpcs lists VPCs in the region, or — when vpcID is given — the subnets and
// security groups within that VPC. This mirrors the extension's "Configure VPC…"
// discovery so the right ids can be passed to `connect`/`create`.
func cmdVpcs(ctx context.Context, cfg aws.Config, vpcID string) error {
	ec := ec2.NewFromConfig(cfg)

	if vpcID == "" {
		out, err := ec.DescribeVpcs(ctx, &ec2.DescribeVpcsInput{})
		if err != nil {
			return err
		}
		w := tabwriter.NewWriter(os.Stdout, 0, 2, 2, ' ', 0)
		fmt.Fprintln(w, "VPC ID\tNAME\tCIDR\tDEFAULT")
		for _, v := range out.Vpcs {
			fmt.Fprintf(w, "%s\t%s\t%s\t%t\n",
				aws.ToString(v.VpcId), dash(nameTag(v.Tags)), aws.ToString(v.CidrBlock), aws.ToBool(v.IsDefault))
		}
		return w.Flush()
	}

	filter := []ec2types.Filter{{Name: aws.String("vpc-id"), Values: []string{vpcID}}}

	subs, err := ec.DescribeSubnets(ctx, &ec2.DescribeSubnetsInput{Filters: filter})
	if err != nil {
		return err
	}
	sw := tabwriter.NewWriter(os.Stdout, 0, 2, 2, ' ', 0)
	fmt.Fprintln(sw, "SUBNET ID\tNAME\tCIDR\tAZ")
	for _, s := range subs.Subnets {
		fmt.Fprintf(sw, "%s\t%s\t%s\t%s\n",
			aws.ToString(s.SubnetId), dash(nameTag(s.Tags)), aws.ToString(s.CidrBlock), aws.ToString(s.AvailabilityZone))
	}
	if err := sw.Flush(); err != nil {
		return err
	}

	sgs, err := ec.DescribeSecurityGroups(ctx, &ec2.DescribeSecurityGroupsInput{Filters: filter})
	if err != nil {
		return err
	}
	fmt.Println()
	gw := tabwriter.NewWriter(os.Stdout, 0, 2, 2, ' ', 0)
	fmt.Fprintln(gw, "SECURITY GROUP ID\tNAME\tDESCRIPTION")
	for _, g := range sgs.SecurityGroups {
		fmt.Fprintf(gw, "%s\t%s\t%s\n",
			aws.ToString(g.GroupId), dash(aws.ToString(g.GroupName)), aws.ToString(g.Description))
	}
	return gw.Flush()
}