package main

import (
	"fmt"
	"io"
	"net/url"
	"slices"
	"strings"

	"github.com/spf13/cobra"

	"jarl/internal/api"
	"jarl/internal/model"
)

func viewCmd() *cobra.Command {
	cmd := &cobra.Command{Use: "view", Aliases: []string{"views"}, Short: "Manage views"}
	list := &cobra.Command{
		Use:   "list",
		Short: "List views in match order",
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			var views []api.View
			if err := c.Get(ctx(), "/views", nil, &views); err != nil {
				return err
			}
			return output(views, func(w io.Writer) {
				fmt.Fprintln(w, "#\tID\tVIEW\tMATCH-CLIENTS\tMATCH-DESTINATIONS\tZONES\tCOLOR")
				for i, v := range views {
					clients, dests := orAny(v.MatchClients), orAny(v.MatchDestinations)
					if v.Limited {
						// No views:read: only the zones they can see.
						clients, dests = "(not shown)", "(not shown)"
					}
					fmt.Fprintf(w, "%d\t%d\t%s\t%s\t%s\t%d\t%s\n", i+1, v.ID, v.Name, clients, dests, v.Zones, orDefault(v.Color))
				}
			})
		},
	}
	var clients, dests []string
	var recursiveOnly, comment, exposure string
	var adopt, cascade, yes, reverseSuggest bool
	viewBody := func(cmd *cobra.Command) map[string]any {
		body := map[string]any{}
		f := cmd.Flags()
		if f.Changed("match-clients") {
			body["match_clients"] = clients
		}
		if f.Changed("match-destinations") {
			body["match_destinations"] = dests
		}
		if f.Changed("recursive-only") {
			switch recursiveOnly {
			case "yes", "true":
				body["match_recursive_only"] = true
			case "no", "false":
				body["match_recursive_only"] = false
			default:
				body["match_recursive_only"] = nil
			}
		}
		if f.Changed("comment") {
			body["comment"] = comment
		}
		if f.Changed("exposure") {
			body["exposure"] = exposure
		}
		if f.Changed("reverse-suggestions") {
			body["reverse_suggestions"] = reverseSuggest
		}
		return body
	}
	addViewFlags := func(c *cobra.Command) {
		c.Flags().StringSliceVar(&clients, "match-clients", nil, "match-clients elements (comma separated or repeated)")
		c.Flags().StringSliceVar(&dests, "match-destinations", nil, "match-destinations elements")
		c.Flags().StringVar(&recursiveOnly, "recursive-only", "", "match-recursive-only: yes, no or default")
		c.Flags().StringVar(&comment, "comment", "", "comment")
		c.Flags().StringVar(&exposure, "exposure", "", "reachable from the internet: auto (worked out), public or private (docs/exposure.md)")
		c.Flags().BoolVar(&reverseSuggest, "reverse-suggestions", true, "suggest reverse zones for the view's addresses (--reverse-suggestions=false: don't; docs/reverse.md)")
	}
	create := &cobra.Command{
		Use:   "create NAME",
		Short: "Create a view (added after the existing views)",
		Example: `  jarl view create internal --match-clients 192.168.0.0/16,localhost --adopt-zones
  jarl view create external --match-clients any`,
		Args: cobra.ExactArgs(1),
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			body := viewBody(cmd)
			body["name"] = args[0]
			if adopt {
				body["adopt_zones"] = true
			}
			resp, err := c.Mutate(ctx(), "POST", "/views", nil, body)
			if err != nil {
				return err
			}
			return report(resp)
		},
	}
	addViewFlags(create)
	create.Flags().BoolVar(&adopt, "adopt-zones", false, "move zones that are not in a view into this one (required for the first view if zones exist)")
	var rename string
	update := &cobra.Command{
		Use:   "update VIEW",
		Short: "Change a view",
		Args:  cobra.ExactArgs(1),
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			body := viewBody(cmd)
			if rename != "" {
				body["name"] = rename
			}
			resp, err := c.Mutate(ctx(), "PATCH", "/views/"+url.PathEscape(args[0]), nil, body)
			if err != nil {
				return err
			}
			return report(resp)
		},
	}
	addViewFlags(update)
	update.Flags().StringVar(&rename, "rename", "", "new name")
	del := &cobra.Command{
		Use:   "delete VIEW",
		Short: "Delete a view",
		Args:  cobra.ExactArgs(1),
		RunE: func(cmd *cobra.Command, args []string) error {
			if cascade && !confirm("Delete view "+args[0]+" with all its zones?", yes) {
				return fmt.Errorf("canceled")
			}
			c, err := newClient()
			if err != nil {
				return err
			}
			qv := q()
			if cascade {
				qv.Set("cascade", "1")
			}
			resp, err := c.Mutate(ctx(), "DELETE", "/views/"+url.PathEscape(args[0]), qv, nil)
			if err != nil {
				return err
			}
			return report(resp)
		},
	}
	del.Flags().BoolVar(&cascade, "cascade", false, "also delete the view's zones")
	del.Flags().BoolVarP(&yes, "yes", "y", false, "don't ask for confirmation")
	order := &cobra.Command{
		Use:   "order VIEW...",
		Short: "Set the order in which views are matched (list every view)",
		Args:  cobra.MinimumNArgs(1),
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			var views []api.View
			if err := c.Get(ctx(), "/views", nil, &views); err != nil {
				return err
			}
			byName := map[string]int64{}
			for _, v := range views {
				byName[strings.ToLower(v.Name)] = v.ID
			}
			var ids []int64
			for _, a := range args {
				id, ok := byName[strings.ToLower(a)]
				if !ok {
					return fmt.Errorf("no view %q", a)
				}
				ids = append(ids, id)
			}
			resp, err := c.Mutate(ctx(), "POST", "/views/order", nil, map[string]any{"ids": ids})
			if err != nil {
				return err
			}
			return report(resp)
		},
	}
	color := &cobra.Command{
		Use:   "color VIEW COLOR",
		Short: "Set the colour the web UI shows a view in",
		Long: "Set the colour the web UI shows a view in, so zones of the same view are easy to spot.\n" +
			"Colours: default (the link colour), " + strings.Join(model.ViewColors, ", ") + ".\n" +
			"This only changes the web UI: it applies at once, with no changeset or deploy.",
		Example: `  jarl view color internal green
  jarl view color internal default`,
		Args: cobra.ExactArgs(2),
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			col := strings.ToLower(args[1])
			if col == "default" {
				col = ""
			} else if !slices.Contains(model.ViewColors, col) {
				return fmt.Errorf("unknown colour %q: use default, %s", args[1], strings.Join(model.ViewColors, ", "))
			}
			var v api.View
			if err := c.Do(ctx(), "PUT", "/views/"+url.PathEscape(args[0])+"/color", nil, api.ViewColor{Color: col}, &v); err != nil {
				return err
			}
			fmt.Printf("View %s: colour %s\n", v.Name, orDefault(v.Color))
			return nil
		},
	}
	var keyNamed bool
	key := &cobra.Command{
		Use:   "key VIEW",
		Short: "Show the TSIG key that selects a view, to query it from anywhere",
		Long: `Every view has a TSIG key (jarl-view-NAME) at the front of its
match-clients: a query signed with it lands in that view, whatever address
it comes from. Jarl signs its own checks of this server with it; use it to
see what a view answers:

  jarl view key external                       # shows a ready dig -y command
  jarl view key external --named-conf > external.key
  dig -k external.key @SERVER adbraun.lol SOA

Showing it needs tsig:write and is recorded in the audit log.`,
		Args: cobra.ExactArgs(1),
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			var k struct {
				Name      string `json:"name"`
				Algorithm string `json:"algorithm"`
				Secret    string `json:"secret"`
			}
			if err := c.Get(ctx(), "/views/"+url.PathEscape(args[0])+"/key", nil, &k); err != nil {
				return err
			}
			if keyNamed {
				fmt.Printf("key %q {\n\talgorithm %s;\n\tsecret %q;\n};\n", k.Name, k.Algorithm, k.Secret)
				return nil
			}
			return output(k, func(w io.Writer) {
				fmt.Fprintf(w, "Key:\t%s\nAlgorithm:\t%s\nSecret:\t%s\ndig:\tdig -y %s:%s:%s @SERVER NAME\n", k.Name, k.Algorithm, k.Secret, k.Algorithm, k.Name, k.Secret)
			})
		},
	}
	key.Flags().BoolVar(&keyNamed, "named-conf", false, "print a key statement (for dig -k FILE)")
	cmd.AddCommand(list, create, update, del, order, color, key)
	return cmd
}

func orDefault(s string) string {
	if s == "" {
		return "default"
	}
	return s
}

func orAny(list []string) string {
	if len(list) == 0 {
		return "any"
	}
	return strings.Join(list, "; ")
}

func aclCmd() *cobra.Command {
	cmd := &cobra.Command{Use: "acl", Aliases: []string{"acls"}, Short: "Manage ACLs (named address match lists)"}
	list := &cobra.Command{
		Use:   "list",
		Short: "List ACLs",
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			var acls []api.ACL
			if err := c.Get(ctx(), "/acls", nil, &acls); err != nil {
				return err
			}
			return output(acls, func(w io.Writer) {
				fmt.Fprintln(w, "ID\tACL\tELEMENTS\tUSED BY")
				for _, a := range acls {
					fmt.Fprintf(w, "%d\t%s\t%s\t%s\n", a.ID, a.Name, strings.Join(a.Elements, "; "), strings.Join(a.UsedBy, ", "))
				}
			})
		},
	}
	var comment, rename string
	var add, remove []string
	create := &cobra.Command{
		Use:     "create NAME ELEMENT...",
		Short:   "Create an ACL",
		Example: `  jarl acl create homelab 192.168.1.0/24 10.10.0.0/16 localhost`,
		Args:    cobra.MinimumNArgs(1),
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			body := map[string]any{"name": args[0], "elements": args[1:], "comment": comment}
			resp, err := c.Mutate(ctx(), "POST", "/acls", nil, body)
			if err != nil {
				return err
			}
			return report(resp)
		},
	}
	create.Flags().StringVar(&comment, "comment", "", "comment")
	var set []string
	update := &cobra.Command{
		Use:   "update ACL",
		Short: "Change an ACL (--add/--remove elements, --set all elements, --rename)",
		Args:  cobra.ExactArgs(1),
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			var cur api.ACL
			if err := c.Get(ctx(), "/acls/"+url.PathEscape(args[0]), nil, &cur); err != nil {
				return err
			}
			body := map[string]any{}
			elems := cur.Elements
			if cmd.Flags().Changed("set") {
				elems = set
			}
			for _, a := range add {
				elems = append(elems, a)
			}
			if len(remove) > 0 {
				drop := map[string]bool{}
				for _, r := range remove {
					drop[r] = true
				}
				var kept []string
				for _, e := range elems {
					if !drop[e] {
						kept = append(kept, e)
					}
				}
				elems = kept
			}
			if elems == nil {
				elems = []string{}
			}
			if cmd.Flags().Changed("set") || len(add) > 0 || len(remove) > 0 {
				body["elements"] = elems
			}
			if rename != "" {
				body["name"] = rename
			}
			if cmd.Flags().Changed("comment") {
				body["comment"] = comment
			}
			if len(body) == 0 {
				return fmt.Errorf("nothing to change (see --help)")
			}
			resp, err := c.Mutate(ctx(), "PATCH", "/acls/"+url.PathEscape(args[0]), nil, body)
			if err != nil {
				return err
			}
			return report(resp)
		},
	}
	update.Flags().StringSliceVar(&add, "add", nil, "add elements")
	update.Flags().StringSliceVar(&remove, "remove", nil, "remove elements (exact text)")
	update.Flags().StringSliceVar(&set, "set", nil, "replace all elements")
	update.Flags().StringVar(&rename, "rename", "", "new name (references are updated)")
	update.Flags().StringVar(&comment, "comment", "", "comment")
	del := &cobra.Command{
		Use:   "delete ACL",
		Short: "Delete an ACL (refused while it is in use)",
		Args:  cobra.ExactArgs(1),
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			resp, err := c.Mutate(ctx(), "DELETE", "/acls/"+url.PathEscape(args[0]), nil, nil)
			if err != nil {
				return err
			}
			return report(resp)
		},
	}
	cmd.AddCommand(list, create, update, del)
	return cmd
}

func tsigCmd() *cobra.Command {
	cmd := &cobra.Command{Use: "tsig", Aliases: []string{"key", "keys"}, Short: "Manage TSIG keys"}
	list := &cobra.Command{
		Use:   "list",
		Short: "List TSIG keys",
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			var keys []api.TSIGKey
			if err := c.Get(ctx(), "/tsig-keys", nil, &keys); err != nil {
				return err
			}
			return output(keys, func(w io.Writer) {
				fmt.Fprintln(w, "ID\tKEY\tALGORITHM\tUSED BY")
				for _, k := range keys {
					fmt.Fprintf(w, "%d\t%s\t%s\t%s\n", k.ID, k.Name, k.Algorithm, strings.Join(k.UsedBy, ", "))
				}
			})
		},
	}
	var secret, algorithm, comment string
	var named bool
	show := &cobra.Command{
		Use:   "show KEY",
		Short: "Show a key and its secret",
		Args:  cobra.ExactArgs(1),
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			var k api.TSIGKey
			if err := c.Get(ctx(), "/tsig-keys/"+url.PathEscape(args[0]), q("secret", "1"), &k); err != nil {
				return err
			}
			if named {
				fmt.Printf("key %q {\n\talgorithm %s;\n\tsecret %q;\n};\n", k.Name, k.Algorithm, k.Secret)
				return nil
			}
			return output(k, func(w io.Writer) {
				fmt.Fprintf(w, "Key:\t%s\nAlgorithm:\t%s\nSecret:\t%s\nUsed by:\t%s\n", k.Name, k.Algorithm, k.Secret, strings.Join(k.UsedBy, ", "))
			})
		},
	}
	show.Flags().BoolVar(&named, "named-conf", false, "print a key statement for another server's named.conf")
	create := &cobra.Command{
		Use:   "create NAME",
		Short: "Create a TSIG key (the secret is generated unless given)",
		Args:  cobra.ExactArgs(1),
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			body := map[string]any{"name": args[0], "algorithm": algorithm, "comment": comment}
			if secret != "" {
				body["secret"] = secret
			}
			resp, err := c.Mutate(ctx(), "POST", "/tsig-keys", nil, body)
			if err != nil {
				return err
			}
			if err := report(resp); err != nil {
				return err
			}
			if resp.Applied && flagOutput == "table" {
				var k api.TSIGKey
				if jsonUnmarshal(resp.Object, &k) == nil && k.Secret != "" {
					fmt.Printf("secret: %s\n", k.Secret)
				}
			}
			return nil
		},
	}
	create.Flags().StringVar(&algorithm, "algorithm", "hmac-sha256", "algorithm")
	create.Flags().StringVar(&secret, "secret", "", "base64 secret (default: generated)")
	create.Flags().StringVar(&comment, "comment", "", "comment")
	rotate := &cobra.Command{
		Use:   "rotate KEY",
		Short: "Give a key a new random secret (or --secret)",
		Args:  cobra.ExactArgs(1),
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			if secret == "" {
				var k api.TSIGKey
				if err := c.Get(ctx(), "/tsig-keys/"+url.PathEscape(args[0]), nil, &k); err != nil {
					return err
				}
				secret = randomSecret(k.Algorithm)
			}
			resp, err := c.Mutate(ctx(), "PATCH", "/tsig-keys/"+url.PathEscape(args[0]), nil, map[string]any{"secret": secret})
			if err != nil {
				return err
			}
			if err := report(resp); err != nil {
				return err
			}
			fmt.Printf("new secret: %s\n", secret)
			return nil
		},
	}
	rotate.Flags().StringVar(&secret, "secret", "", "the new secret (default: generated)")
	del := &cobra.Command{
		Use:   "delete KEY",
		Short: "Delete a key (refused while it is in use)",
		Args:  cobra.ExactArgs(1),
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			resp, err := c.Mutate(ctx(), "DELETE", "/tsig-keys/"+url.PathEscape(args[0]), nil, nil)
			if err != nil {
				return err
			}
			return report(resp)
		},
	}
	cmd.AddCommand(list, show, create, rotate, del)
	return cmd
}

func optionCmd() *cobra.Command {
	cmd := &cobra.Command{Use: "option", Aliases: []string{"options", "opt"}, Short: "Manage named options (server, view, zone, top-level)"}
	var view, zone, zoneView string
	var toplevel bool
	scopeArgs := func(c *cobra.Command) {
		c.Flags().StringVar(&view, "view", "", "options of this view")
		c.Flags().StringVar(&zone, "zone", "", "options of this zone")
		c.Flags().StringVar(&zoneView, "zone-view", "", "view of --zone")
		c.Flags().BoolVar(&toplevel, "toplevel", false, "top-level statements (logging, controls, ...)")
	}
	scope := func() (string, int64, error) {
		c, err := newClient()
		if err != nil {
			return "", 0, err
		}
		switch {
		case zone != "":
			id, err := resolveZoneID(c, zone, zoneView)
			return model.ScopeZone, id, err
		case view != "":
			var v api.View
			if err := c.Get(ctx(), "/views/"+url.PathEscape(view), nil, &v); err != nil {
				return "", 0, err
			}
			return model.ScopeView, v.ID, nil
		case toplevel:
			return model.ScopeTopLevel, 0, nil
		}
		return model.ScopeOptions, 0, nil
	}
	list := &cobra.Command{
		Use:   "list",
		Short: "List options (server options by default)",
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			qv := q()
			if view != "" || zone != "" || toplevel || !cmd.Flags().Changed("all") {
				sc, id, err := scope()
				if err != nil {
					return err
				}
				qv = q("scope", sc, "scope_id", fmt.Sprint(id))
			}
			if all {
				qv = q()
			}
			var opts []api.Option
			if err := c.Get(ctx(), "/options", qv, &opts); err != nil {
				return err
			}
			return output(opts, func(w io.Writer) {
				fmt.Fprintln(w, "ID\tWHERE\tOPTION\tVALUE")
				for _, o := range opts {
					fmt.Fprintf(w, "%d\t%s\t%s\t%s\n", o.ID, o.Where, o.Name, o.Value)
				}
			})
		},
	}
	scopeArgs(list)
	list.Flags().BoolVar(&all, "all", false, "options of every scope")
	var comment string
	set := &cobra.Command{
		Use:   "set NAME [VALUE...]",
		Short: "Set an option (replaces an existing option of the same name)",
		Long: `Set an option; VALUE is named.conf syntax without the trailing semicolon.

It replaces the option of that name. Statements told apart by the name
after the keyword (tls NAME, key NAME, remote-servers NAME, http NAME,
dnssec-policy NAME, server ADDRESS, ...) replace only the one with that
name: setting tls cloudflare leaves tls quad9 alone. --add adds another
instance of any other option that may occur several times.

  jarl option set recursion no
  jarl option set allow-recursion '{ homelab; localhost; }'
  jarl option set forwarders '{ 1.1.1.1; 9.9.9.9; }'
  jarl option set allow-transfer '{ key xfer; }' --zone example.com
  jarl option set logging '{ channel q { file "/var/log/named/q.log"; }; category queries { q; }; }' --toplevel`,
		Args: cobra.MinimumNArgs(1),
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			sc, id, err := scope()
			if err != nil {
				return err
			}
			value := strings.Join(args[1:], " ")
			var opts []api.Option
			if err := c.Get(ctx(), "/options", q("scope", sc, "scope_id", fmt.Sprint(id)), &opts); err != nil {
				return err
			}
			body := map[string]any{"value": value}
			if cmd.Flags().Changed("comment") {
				body["comment"] = comment
			}
			label := optionLabel(strings.ToLower(args[0]), value)
			for _, o := range opts {
				if label != "" && optionLabel(o.Name, o.Value) != label {
					continue // another tls (key, server, ...) statement
				}
				if o.Name == strings.ToLower(args[0]) && !multiple {
					resp, err := c.Mutate(ctx(), "PATCH", fmt.Sprintf("/options/%d", o.ID), nil, body)
					if err != nil {
						return err
					}
					return report(resp)
				}
			}
			body["scope"], body["scope_id"], body["name"] = sc, id, args[0]
			resp, err := c.Mutate(ctx(), "POST", "/options", nil, body)
			if err != nil {
				return err
			}
			return report(resp)
		},
	}
	scopeArgs(set)
	set.Flags().StringVar(&comment, "comment", "", "comment")
	set.Flags().BoolVar(&multiple, "add", false, "add another instance instead of replacing (for options that may occur several times)")
	unset := &cobra.Command{
		Use:   "unset NAME [LABEL] | unset --id ID",
		Short: "Remove an option (BIND's default applies again)",
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			if optID > 0 {
				resp, err := c.Mutate(ctx(), "DELETE", fmt.Sprintf("/options/%d", optID), nil, nil)
				if err != nil {
					return err
				}
				return report(resp)
			}
			if len(args) < 1 || len(args) > 2 {
				return fmt.Errorf("give the option name (and the name after it, for tls NAME and the like) or --id")
			}
			sc, id, err := scope()
			if err != nil {
				return err
			}
			var opts []api.Option
			if err := c.Get(ctx(), "/options", q("scope", sc, "scope_id", fmt.Sprint(id)), &opts); err != nil {
				return err
			}
			var matches []api.Option
			for _, o := range opts {
				if o.Name == strings.ToLower(args[0]) && (len(args) == 1 || strings.EqualFold(optionLabel(o.Name, o.Value), strings.Trim(args[1], `"`))) {
					matches = append(matches, o)
				}
			}
			switch len(matches) {
			case 0:
				return fmt.Errorf("option %s is not set here", strings.Join(args, " "))
			case 1:
			default:
				var labels []string
				for _, o := range matches {
					if l := optionLabel(o.Name, o.Value); l != "" {
						labels = append(labels, l)
					}
				}
				if len(labels) == len(matches) {
					return fmt.Errorf("option %s is set %d times (%s); say which: jarl option unset %s %s", args[0], len(matches), strings.Join(labels, ", "), args[0], labels[0])
				}
				return fmt.Errorf("option %s is set %d times; remove one with --id", args[0], len(matches))
			}
			resp, err := c.Mutate(ctx(), "DELETE", fmt.Sprintf("/options/%d", matches[0].ID), nil, nil)
			if err != nil {
				return err
			}
			return report(resp)
		},
	}
	scopeArgs(unset)
	unset.Flags().Int64Var(&optID, "id", 0, "remove the option with this ID")
	describe := &cobra.Command{
		Use:   "describe [NAME]",
		Short: "Describe options from the BIND 9.20 catalog",
		Args:  cobra.MaximumNArgs(1),
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			cs := "options"
			switch {
			case toplevel:
				cs = "toplevel"
			case view != "":
				cs = "view"
			case zone != "":
				cs = "zone:" + zoneType
			}
			var stmts []struct {
				Name        string `json:"name"`
				Grammar     string `json:"grammar"`
				Kind        string `json:"kind"`
				Status      string `json:"status"`
				Description string `json:"description"`
			}
			if err := c.Get(ctx(), "/catalog/options", q("scope", cs), &stmts); err != nil {
				return err
			}
			for _, s := range stmts {
				if len(args) == 1 && s.Name != args[0] {
					continue
				}
				if len(args) == 0 {
					fmt.Printf("%-32s %s\n", s.Name, s.Description)
					continue
				}
				fmt.Printf("%s (%s)%s\n  %s\n\n%s\n", s.Name, s.Kind, statusText(s.Status), s.Description, s.Grammar)
				return nil
			}
			if len(args) == 1 {
				return fmt.Errorf("%s is not an option in scope %s", args[0], cs)
			}
			return nil
		},
	}
	scopeArgs(describe)
	describe.Flags().StringVar(&zoneType, "zone-type", "primary", "with --zone: the zone type")
	generated := &cobra.Command{
		Use:   "generated",
		Short: "What Jarl adds to named.conf by itself, why, and what controls it",
		Args:  cobra.NoArgs,
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			var gen []struct {
				Where   string `json:"where"`
				Text    string `json:"text"`
				Why     string `json:"why"`
				Setting string `json:"setting"`
			}
			if err := c.Get(ctx(), "/options/generated", nil, &gen); err != nil {
				return err
			}
			return output(gen, func(w io.Writer) {
				for i, g := range gen {
					if i > 0 {
						fmt.Fprintln(w)
					}
					fmt.Fprintf(w, "# %s: %s\n# controlled by: %s\n%s\n", g.Where, g.Why, g.Setting, g.Text)
				}
			})
		},
	}
	cmd.AddCommand(list, set, unset, describe, generated)
	return cmd
}

var (
	all      bool
	multiple bool
	optID    int64
	zoneType string
)

func statusText(s string) string {
	if s == "" {
		return ""
	}
	return " [" + s + "]"
}

func settingsCmd() *cobra.Command {
	cmd := &cobra.Command{Use: "settings", Short: "Show or change Jarl's defaults for new zones"}
	show := &cobra.Command{
		Use:   "show",
		Short: "Show settings",
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			var s model.Settings
			if err := c.Get(ctx(), "/settings", nil, &s); err != nil {
				return err
			}
			return output(s, func(w io.Writer) {
				fmt.Fprintf(w, "Name servers:\t%s\nContact:\t%s\nDefault TTL:\t%d\nRefresh/retry/expire:\t%d/%d/%d\nNegative TTL:\t%d\nSerial policy:\t%s\n",
					strings.Join(s.Nameservers, ", "), s.RName, s.DefaultTTL, s.Refresh, s.Retry, s.Expire, s.NegativeTTL, s.SerialPolicy)
			})
		},
	}
	var ns []string
	var contact, policy, srvExposure string
	var ttl, refresh, retry, expire, neg uint32
	set := &cobra.Command{
		Use:   "set",
		Short: "Change settings",
		RunE: func(cmd *cobra.Command, args []string) error {
			c, err := newClient()
			if err != nil {
				return err
			}
			body := map[string]any{}
			f := cmd.Flags()
			if f.Changed("ns") {
				body["nameservers"] = ns
			}
			if f.Changed("contact") {
				body["rname"] = contact
			}
			if f.Changed("serial-policy") {
				body["serial_policy"] = policy
			}
			if f.Changed("exposure") {
				body["exposure"] = srvExposure
			}
			for name, v := range map[string]uint32{"ttl": ttl, "refresh": refresh, "retry": retry, "expire": expire, "negative-ttl": neg} {
				if f.Changed(name) {
					key := map[string]string{"ttl": "default_ttl", "negative-ttl": "negative_ttl"}[name]
					if key == "" {
						key = name
					}
					body[key] = v
				}
			}
			if len(body) == 0 {
				return fmt.Errorf("nothing to change (see --help)")
			}
			resp, err := c.Mutate(ctx(), "PATCH", "/settings", nil, body)
			if err != nil {
				return err
			}
			return report(resp)
		},
	}
	set.Flags().StringSliceVar(&ns, "ns", nil, "default name servers")
	set.Flags().StringVar(&contact, "contact", "", "default SOA contact")
	set.Flags().StringVar(&policy, "serial-policy", "", "date, increment or unixtime")
	set.Flags().StringVar(&srvExposure, "exposure", "", "without views: is the server reachable from the internet? auto, public or private (docs/exposure.md)")
	set.Flags().Uint32Var(&ttl, "ttl", 0, "default TTL")
	set.Flags().Uint32Var(&refresh, "refresh", 0, "SOA refresh")
	set.Flags().Uint32Var(&retry, "retry", 0, "SOA retry")
	set.Flags().Uint32Var(&expire, "expire", 0, "SOA expire")
	set.Flags().Uint32Var(&neg, "negative-ttl", 0, "SOA minimum")
	cmd.AddCommand(show, set)
	return cmd
}

// labelled are the statements told apart by the name after the keyword:
// tls quad9 { ... }, key xfer { ... }, server 192.0.2.1 { ... }.
var labelled = map[string]bool{"tls": true, "http": true, "key": true, "remote-servers": true, "primaries": true, "masters": true,
	"parental-agents": true, "dnssec-policy": true, "key-store": true, "server": true, "view": true, "acl": true, "zone": true}

// optionLabel returns the name a labelled statement's value starts with
// ("quad9" for tls quad9 { ... }), lowercase; "" for other statements.
func optionLabel(name, value string) string {
	if !labelled[name] {
		return ""
	}
	v := strings.TrimSpace(value)
	if v == "" || strings.HasPrefix(v, "{") {
		return ""
	}
	if strings.HasPrefix(v, `"`) {
		if end := strings.Index(v[1:], `"`); end >= 0 {
			return strings.ToLower(v[1 : end+1])
		}
	}
	end := strings.IndexAny(v, " \t\n{;")
	if end < 0 {
		end = len(v)
	}
	return strings.ToLower(v[:end])
}