// Copyright (c) 2026 Lark Technologies Pte. Ltd.
// SPDX-License-Identifier: MIT

package cmd

import (
	"context"
	"errors"
	"fmt"
	"os"
	"sort"
	"strings"

	"github.com/larksuite/cli/cmd/service"
	"github.com/larksuite/cli/errs"
	"github.com/larksuite/cli/extension/platform"
	"github.com/larksuite/cli/internal/build"
	"github.com/larksuite/cli/internal/cmdmeta"
	"github.com/larksuite/cli/internal/cmdpolicy"
	"github.com/larksuite/cli/internal/cmdutil"
	"github.com/larksuite/cli/internal/deprecation"
	"github.com/larksuite/cli/internal/hook"
	"github.com/larksuite/cli/internal/output"
	"github.com/larksuite/cli/internal/skillscheck"
	"github.com/larksuite/cli/internal/suggest"
	"github.com/larksuite/cli/internal/update"
	"github.com/spf13/cobra"
	"github.com/spf13/pflag"
)

const rootLong = `lark-cli — Lark/Feishu CLI tool.

AGENT QUICKSTART (driving this as an agent? start here):
    Browse commands:  lark-cli <domain> --help            # +shortcuts (preferred) and raw API resources
    Inspect a call:   lark-cli schema <service>.<resource>.<method>   # params, types, scopes, examples
    Prefer a +shortcut over the raw API resource when one matches the task.
    Risk: each command's --help shows read | write | high-risk-write;
          high-risk-write needs --yes, only after the user confirms.
    On any API call: --jq <expr> filters JSON output, --dry-run previews the request (runs nothing).

EXAMPLES (one per command style, in order of preference):
    lark-cli calendar +agenda                                       # +shortcut — a high-level task, prefer these
    lark-cli mail user_mailbox.messages list --user-mailbox-id me   # typed command for one API method
    lark-cli schema mail.user_mailbox.messages.list                 # inspect a method's params before calling
    lark-cli api GET /open-apis/calendar/v4/calendars               # raw escape hatch — any endpoint by HTTP path`

// rootUsageTemplate is cobra's default usage template with two root-only
// additions gated on {{if not .HasParent}}: a curated multi-form Usage synopsis
// (replacing cobra's generic "[flags] / [command]") and a human skills-setup
// footer. Subcommands render the stock template unchanged. The rest is verbatim
// cobra so the command groups and flags are untouched.
const rootUsageTemplate = `{{if .HasParent}}Usage:{{if .Runnable}}
  {{.UseLine}}{{end}}{{if .HasAvailableSubCommands}}
  {{.CommandPath}} [command]{{end}}{{else}}Usage:
  lark-cli <command> [subcommand] [method] [flags]
  lark-cli api <method> <path> [--params <json>] [--data <json>]
  lark-cli schema <service.resource.method>{{end}}{{if gt (len .Aliases) 0}}

Aliases:
  {{.NameAndAliases}}{{end}}{{if .HasExample}}

Examples:
{{.Example}}{{end}}{{if .HasAvailableSubCommands}}{{$cmds := .Commands}}{{if eq (len .Groups) 0}}

Available Commands:{{range $cmds}}{{if (or .IsAvailableCommand (eq .Name "help"))}}
  {{rpad .Name .NamePadding }} {{.Short}}{{end}}{{end}}{{else}}{{range $group := .Groups}}

{{.Title}}{{range $cmds}}{{if (and (eq .GroupID $group.ID) (or .IsAvailableCommand (eq .Name "help")))}}
  {{rpad .Name .NamePadding }} {{.Short}}{{end}}{{end}}{{end}}{{if not .AllChildCommandsHaveGroup}}

Additional Commands:{{range $cmds}}{{if (and (eq .GroupID "") (or .IsAvailableCommand (eq .Name "help")))}}
  {{rpad .Name .NamePadding }} {{.Short}}{{end}}{{end}}{{end}}{{end}}{{end}}{{if .HasAvailableLocalFlags}}

Flags:
{{.LocalFlags.FlagUsages | trimTrailingWhitespaces}}{{end}}{{if .HasAvailableInheritedFlags}}

Global Flags:
{{.InheritedFlags.FlagUsages | trimTrailingWhitespaces}}{{end}}{{if .HasHelpSubCommands}}

Additional help topics:{{range .Commands}}{{if .IsAdditionalHelpTopicCommand}}
  {{rpad .CommandPath .CommandPathPadding}} {{.Short}}{{end}}{{end}}{{end}}{{if .HasAvailableSubCommands}}

Use "{{.CommandPath}} [command] --help" for more information about a command.{{end}}{{if not .HasParent}}

Skills setup (one-time, humans): npx skills add larksuite/cli -g -y — https://github.com/larksuite/cli#agent-skills{{end}}
`

// Execute runs the root command and returns the process exit code.
// rawInvocationArgs holds os.Args[1:] captured at Execute() entry. cobra's
// UnknownFlags whitelist (installUnknownSubcommandGuard) swallows unknown flags
// before they reach a group's RunE, so unknownSubcommandRunE re-derives them
// from here. It stays nil in unit tests that invoke a RunE directly with
// explicit args — correct, since those don't exercise the whitelist path.
var rawInvocationArgs []string

func Execute() int {
	rawInvocationArgs = os.Args[1:]
	inv, err := BootstrapInvocationContext(os.Args[1:])
	if err != nil {
		fmt.Fprintln(os.Stderr, "Error:", err)
		return 1
	}
	configureFlagCompletions(os.Args)

	ctx := context.Background()
	f, rootCmd, reg := buildInternal(
		ctx, inv,
		WithIO(os.Stdin, os.Stdout, os.Stderr),
		HideProfile(isSingleAppMode()),
	)

	// --- Notices (non-blocking) ---
	if !isCompletionCommand(os.Args) {
		setupNotices()
	}

	runErr := rootCmd.Execute()

	// Fire Shutdown lifecycle hooks regardless of run outcome.
	// emitShutdown imposes a 2s total deadline and never propagates handler
	// errors (Emit's documented Shutdown contract), so it cannot block exit
	// or alter the user-visible exit code.
	if reg != nil && !isCompletionCommand(os.Args) {
		_ = hook.Emit(ctx, reg, platform.Shutdown, runErr)
	}

	if runErr != nil {
		return handleRootError(f, runErr)
	}
	return 0
}

// setupNotices wires both the binary update notice and the skills
// staleness notice into output.PendingNotice as a composed function.
// Each provider populates an independent key under _notice; either
// or both may be present in any given envelope.
func setupNotices() {
	// Binary update — synchronous cache check + async refresh
	if info := update.CheckCached(build.Version); info != nil {
		update.SetPending(info)
	}
	ver := build.Version
	go func() {
		defer func() {
			if r := recover(); r != nil {
				fmt.Fprintf(os.Stderr, "update check panic: %v\n", r)
			}
		}()
		update.RefreshCache(ver)
		if update.GetPending() == nil {
			if info := update.CheckCached(ver); info != nil {
				update.SetPending(info)
			}
		}
	}()

	// Skills check — synchronous, local-only (no network, no goroutine).
	skillscheck.Init(build.Version)

	// Composed notice provider — emits keys only when each pending is set.
	output.PendingNotice = composePendingNotice
}

// composePendingNotice merges all process-level pending notices (available
// update, skills/binary drift, deprecated-command alias) into the map surfaced
// as the JSON "_notice" envelope field. Returns nil when nothing is pending.
// Extracted from Execute so the composition is unit-testable.
func composePendingNotice() map[string]interface{} {
	notice := map[string]interface{}{}
	if info := update.GetPending(); info != nil {
		notice["update"] = map[string]interface{}{
			"current": info.Current,
			"latest":  info.Latest,
			"message": info.Message(),
			"command": "lark-cli update",
		}
	}
	if stale := skillscheck.GetPending(); stale != nil {
		notice["skills"] = map[string]interface{}{
			"current": stale.Current,
			"target":  stale.Target,
			"message": stale.Message(),
			"command": "lark-cli update",
		}
	}
	if dep := deprecation.GetPending(); dep != nil {
		entry := map[string]interface{}{
			"command": dep.Command,
			"message": dep.Message(),
			"action":  "lark-cli update",
		}
		if dep.Replacement != "" {
			entry["replacement"] = dep.Replacement
		}
		if dep.Skill != "" {
			entry["skill"] = dep.Skill
		}
		notice["deprecated_command"] = entry
	}
	if len(notice) == 0 {
		return nil
	}
	return notice
}

// isCompletionCommand returns true if args indicate a shell completion request.
// Update notifications and Shutdown lifecycle emits must be suppressed for
// these to avoid corrupting machine-parseable completion output and to avoid
// firing plugin Shutdown handlers on every Tab keystroke.
//
// Cobra dispatches BOTH "__complete" and its alias "__completeNoDesc" through
// the same hidden subcommand (see cobra/completions.go ShellCompRequestCmd /
// ShellCompNoDescRequestCmd). Check both, otherwise bash/zsh completion
// (which often uses NoDesc) silently bypasses the gate.
func isCompletionCommand(args []string) bool {
	for _, arg := range args {
		if arg == "completion" || arg == "__complete" || arg == "__completeNoDesc" {
			return true
		}
	}
	return false
}

// configureFlagCompletions enables cmdutil.RegisterFlagCompletion only when
// the invocation will actually serve a __complete request.
func configureFlagCompletions(args []string) {
	cmdutil.SetFlagCompletionsEnabled(isCompletionCommand(args))
}

// handleRootError dispatches a command error to the appropriate handler
// and returns the process exit code.
//
// Dispatch order:
//  1. Typed errors from errs/ (e.g. *errs.PermissionError, *errs.APIError,
//     *errs.SecurityPolicyError, *errs.AuthenticationError, *errs.ConfigError):
//     render via the typed envelope writer, which lifts extension fields
//     (missing_scopes, console_url, challenge_url, ...) to the top level.
//     Routed by errs.CategoryOf via ExitCodeOf. Auth and config errors are
//     constructed typed at their origin (internal/auth, internal/core), so the
//     dispatcher no longer promotes any legacy shape here.
//  2. PartialFailure / BareError signals: the result envelope is already on
//     stdout; honor the exit code and write nothing to stderr.
//  3. Residual cobra usage errors (missing required flag, unknown command,
//     argument validation): typed as an invalid_argument envelope (exit 2),
//     matching the explicit flag/subcommand guards. Flag parse errors are
//     already typed upstream by the root FlagErrorFunc.
func handleRootError(f *cmdutil.Factory, err error) int {
	errOut := f.IOStreams.ErrOut

	// When the typed error is a need_user_authorization signal, fold in the
	// current command's declared scopes as a Hint so the user/AI sees the
	// concrete scope(s) to re-auth with. The hint is computed on the fly from
	// local shortcut/service metadata — it never depends on server state.
	if !errs.IsRaw(err) {
		applyNeedAuthorizationHint(f, err)
	}

	// Staged dispatch: capture the typed exit code BEFORE attempting the
	// envelope write. WriteTypedErrorEnvelope is best-effort on the wire
	// (partial-write still returns true) so the exit code we read here is
	// preserved even if stderr is torn — torn stderr must not downgrade
	// typed exits 3/4/6/10 to the plain "Error:" path with exit 1.
	// WriteTypedErrorEnvelope still returns false when err carries no
	// Problem; in that case we fall through to the signal / plain-text paths.
	typedExit := output.ExitCodeOf(err)
	if output.WriteTypedErrorEnvelope(errOut, err, string(f.ResolvedIdentity)) {
		return typedExit
	}

	// Partial-failure (batch / multi-status): the ok:false result envelope is
	// already on stdout; set the exit code and write nothing to stderr.
	var pfErr *output.PartialFailureError
	if errors.As(err, &pfErr) {
		return pfErr.Code
	}

	// Silent-exit signal (e.g. `auth check` predicate, or `update --json`):
	// stdout already carries the result; honor the requested exit code and
	// write nothing to stderr.
	var bareErr *output.BareError
	if errors.As(err, &bareErr) {
		return bareErr.Code
	}

	// Errors reaching here are untyped: every RunE returns a typed errs.* error
	// and flag-parse errors are typed by the root FlagErrorFunc. The remainder
	// is either a cobra usage mistake (missing required flag, unknown command,
	// wrong arg count), which cobra surfaces as a plain error identified by its
	// stable text — the same external contract unknownFlagName relies on — or an
	// untyped error that leaked past the typed boundary. Classify the former as
	// invalid_argument (exit 2, like the explicit guards); treat the latter as an
	// internal fault (exit 5) rather than blaming the user's input. The message
	// is preserved either way, and the typed envelope still carries any pending
	// deprecation notice.
	var fallback error
	if isCobraUsageError(err) {
		fallback = errs.NewValidationError(errs.SubtypeInvalidArgument, "%s", err.Error())
	} else {
		fallback = errs.NewInternalError(errs.SubtypeUnknown, "%s", err.Error()).WithCause(err)
	}
	output.WriteTypedErrorEnvelope(errOut, fallback, string(f.ResolvedIdentity))
	return output.ExitCodeOf(fallback)
}

// cobraUsageErrorMarkers are the stable error-text fragments cobra / pflag
// (pinned at v1.10.2) emit for usage mistakes — missing required flag, unknown
// command / flag, wrong argument count. Cobra surfaces these as plain errors,
// not a typed value we can match on, so the dispatcher recognizes them by text;
// this is the same external contract unknownFlagName already depends on. A
// residual error matching none of these has leaked the typed boundary and is
// treated as an internal fault, not a user error.
var cobraUsageErrorMarkers = []string{
	"unknown command ",
	"unknown flag: ",
	"unknown shorthand",
	"required flag(s) ",
	"flag needs an argument",
	"bad flag syntax:",
	"no such flag ",
	"invalid argument ",
	"arg(s), ", // accepts / requires N arg(s), received / only received M
}

// isCobraUsageError reports whether err is a cobra / pflag usage mistake,
// identified by the stable error text of the pinned cobra version.
func isCobraUsageError(err error) bool {
	msg := err.Error()
	for _, m := range cobraUsageErrorMarkers {
		if strings.Contains(msg, m) {
			return true
		}
	}
	return false
}

// installUnknownSubcommandGuard replaces cobra's silent help fallback on
// group commands (no Run/RunE) with an unknown_subcommand error.
//
// IMPORTANT: every command modified here is also tagged with
// cmdpolicy.AnnotationPureGroup so the user-layer policy engine
// continues to treat the command as a pure parent group. Without the
// tag, the RunE injection here would flip Runnable()=true and a user
// rule like `max_risk: read` would deny every `<group> --help` call
// with reason_code=risk_not_annotated.
func installUnknownSubcommandGuard(cmd *cobra.Command) {
	if cmd.HasSubCommands() && cmd.Run == nil && cmd.RunE == nil {
		cmd.RunE = unknownSubcommandRunE
		// Route an unknown subcommand to unknownSubcommandRunE even when flags
		// are also present (e.g. `sheets +cells-find --url ...`). A pure group
		// consumes no flags itself, so unknown flags belong to the (missing)
		// subcommand; whitelisting them here prevents cobra from erroring on the
		// flag first and printing usage instead of our structured suggestion.
		cmd.FParseErrWhitelist.UnknownFlags = true
		if cmd.Annotations == nil {
			cmd.Annotations = map[string]string{}
		}
		cmd.Annotations[cmdpolicy.AnnotationPureGroup] = "true"
	}
	for _, c := range cmd.Commands() {
		installUnknownSubcommandGuard(c)
	}
}

// unknownSubcommandRunE replaces cobra's silent help fallback on group commands
// with a typed *errs.ValidationError: a flag that belongs to a missing
// subcommand, a misplaced subcommand-only flag, or an unknown subcommand name
// each fail structured (exit 2) instead of degrading to help + exit 0.
func unknownSubcommandRunE(cmd *cobra.Command, args []string) error {
	if len(args) == 0 {
		// A bare group (e.g. `sheets`), or one carrying only group-valid flags
		// like the global --profile, legitimately prints help. But a flag that
		// belongs to a (missing) subcommand is a user error: the guard's
		// FParseErrWhitelist swallows such flags and leaves args empty, so without
		// the checks below they would silently fall through to help + exit 0 —
		// letting an agent mistake a malformed call (`im --format json`,
		// `sheets --badflag`) for success. Recover the swallowed tokens from the
		// raw invocation and fail structured instead.
		flags := flagTokensInArgs(rawInvocationArgs)
		if len(flags) == 0 {
			return cmd.Help()
		}
		if unknown := unknownFlagTokens(cmd, rawInvocationArgs); len(unknown) > 0 {
			verr := errs.NewValidationError(errs.SubtypeInvalidArgument,
				"unknown flag %s before a subcommand for %q", strings.Join(unknown, ", "), cmd.CommandPath()).
				WithHint("flags belong to a subcommand; run `%s --help` to list subcommands and their flags", cmd.CommandPath())
			for _, flag := range unknown {
				verr.WithParams(errs.InvalidParam{Name: flag, Reason: "unknown flag before a subcommand"})
			}
			return verr
		}
		// The remaining flags are all defined somewhere in the tree. Those valid
		// on the group itself or inherited (e.g. the global --profile) do not
		// require a subcommand, so a bare group carrying only those still prints
		// help. Anything left belongs to a subcommand that was omitted
		// (e.g. `im --format json`): distinct from unknown_flag — the flags are
		// real, the subcommand is what's missing.
		misplaced := subcommandOnlyFlagTokens(cmd, rawInvocationArgs)
		if len(misplaced) == 0 {
			return cmd.Help()
		}
		verr := errs.NewValidationError(errs.SubtypeInvalidArgument,
			"missing subcommand for %q; flag %s belongs to a subcommand, not the group", cmd.CommandPath(), strings.Join(misplaced, ", ")).
			WithHint("run `%s --help` to list subcommands and their flags", cmd.CommandPath())
		for _, flag := range misplaced {
			verr.WithParams(errs.InvalidParam{Name: flag, Reason: "flag belongs to a subcommand, not the group"})
		}
		return verr
	}
	unknown := args[0]
	available, deprecated := availableSubcommandNames(cmd)
	// Rank suggestions across both current and deprecated names so a mistyped
	// legacy command (e.g. +raed → +read) still resolves; the alias stays
	// runnable and self-flags via the _notice on execution.
	suggestions := suggest.Closest(unknown, append(append([]string{}, available...), deprecated...), 6)
	msg := fmt.Sprintf("unknown subcommand %q for %q", unknown, cmd.CommandPath())
	hint := fmt.Sprintf("run `%s --help` to see available subcommands", cmd.CommandPath())
	if len(suggestions) > 0 {
		hint = fmt.Sprintf("did you mean one of: %s? (run `%s --help` for the full list)",
			strings.Join(suggestions, ", "), cmd.CommandPath())
	}
	// Record the offending subcommand and its ranked candidates as a param with
	// machine-readable Suggestions so an agent can retry without parsing the
	// hint; the hint carries the same candidates as prose.
	return errs.NewValidationError(errs.SubtypeInvalidArgument, "%s", msg).
		WithParams(errs.InvalidParam{Name: unknown, Reason: "unknown subcommand", Suggestions: suggestions}).
		WithHint("%s", hint)
}

// flagTokensInArgs returns the flag-like tokens (-x, --foo, --foo=bar) in
// rawArgs, stopping at the "--" positional terminator. Whether a flag is
// defined is not considered (see unknownFlagTokens for that). A pure group
// with any flag token but no subcommand is a user error — a pure group
// consumes no flags of its own, so the flag must belong to a subcommand — so
// the caller fails structured instead of falling through to help.
func flagTokensInArgs(rawArgs []string) []string {
	var toks []string
	for _, a := range rawArgs {
		if a == "--" {
			break // everything after -- is positional
		}
		if len(a) < 2 || a[0] != '-' {
			continue
		}
		toks = append(toks, a)
	}
	return toks
}

// unknownFlagTokens returns the flag tokens in rawArgs that cmd does not define
// (on itself, inherited, or any direct subcommand). installUnknownSubcommandGuard
// whitelists unknown flags on pure groups so a mistyped subcommand still reaches
// the suggestion path; the side effect is that flags before a subcommand are
// swallowed. This recovers the genuinely-unknown ones so the caller can name
// them in a "did you mean" envelope.
func unknownFlagTokens(cmd *cobra.Command, rawArgs []string) []string {
	var unknown []string
	for _, a := range flagTokensInArgs(rawArgs) {
		name := strings.SplitN(strings.TrimLeft(a, "-"), "=", 2)[0]
		if name != "" && !flagDefinedInTree(cmd, name) {
			unknown = append(unknown, a)
		}
	}
	return unknown
}

// flagKnownOnGroup reports whether name is a flag defined on cmd itself or
// inherited (a global persistent flag like --profile) — i.e. valid on the bare
// group and therefore not requiring a subcommand.
func flagKnownOnGroup(cmd *cobra.Command, name string) bool {
	short := len(name) == 1
	lookup := func(fs *pflag.FlagSet) bool {
		if short {
			return fs.ShorthandLookup(name) != nil
		}
		return fs.Lookup(name) != nil
	}
	return lookup(cmd.Flags()) || lookup(cmd.InheritedFlags())
}

// subcommandOnlyFlagTokens returns the flag tokens in rawArgs that are valid on
// a subcommand of cmd but not on cmd itself/inherited — flags supplied while
// omitting the subcommand they belong to (`im --format json`). Global flags
// valid on the bare group (e.g. --profile) are excluded so
// `lark-cli --profile p im` still prints help rather than erroring.
func subcommandOnlyFlagTokens(cmd *cobra.Command, rawArgs []string) []string {
	var misplaced []string
	for _, a := range flagTokensInArgs(rawArgs) {
		name := strings.SplitN(strings.TrimLeft(a, "-"), "=", 2)[0]
		if name == "" || flagKnownOnGroup(cmd, name) {
			continue
		}
		if flagDefinedInTree(cmd, name) {
			misplaced = append(misplaced, a)
		}
	}
	return misplaced
}

// flagDefinedInTree reports whether name is defined on cmd, its inherited
// (persistent) flags, or any direct subcommand. The subcommand case covers a
// user who merely omitted the subcommand — e.g. `sheets --format json`, where
// --format is injected on every leaf shortcut, not on the group — so only a
// genuinely unknown flag like `sheets --badflag` is reported.
func flagDefinedInTree(cmd *cobra.Command, name string) bool {
	short := len(name) == 1
	known := func(c *cobra.Command, inherited bool) bool {
		fs := c.Flags()
		if inherited {
			fs = c.InheritedFlags()
		}
		if short {
			return fs.ShorthandLookup(name) != nil
		}
		return fs.Lookup(name) != nil
	}
	if known(cmd, false) || known(cmd, true) {
		return true
	}
	for _, c := range cmd.Commands() {
		if known(c, false) {
			return true
		}
	}
	return false
}

// availableSubcommandNames returns the invokable subcommand names of cmd, split
// into current commands and backward-compatibility aliases (those tagged into
// the deprecated cobra group via cmdutil.DeprecatedGroupID). Both slices are
// sorted; hidden commands plus help/completion are omitted.
func availableSubcommandNames(cmd *cobra.Command) (available, deprecated []string) {
	for _, c := range cmd.Commands() {
		if c.Hidden || !c.IsAvailableCommand() {
			continue
		}
		name := c.Name()
		if name == "help" || name == "completion" {
			continue
		}
		if cmdutil.IsDeprecatedCommand(c) {
			deprecated = append(deprecated, name)
		} else {
			available = append(available, name)
		}
	}
	sort.Strings(available)
	sort.Strings(deprecated)
	return available, deprecated
}

// Root command help groups, so an agent sees content domains, agent tooling, and
// CLI management as distinct blocks instead of one flat alphabetical dump.
const (
	groupDomains    = "lark-domains"
	groupTooling    = "agent-tooling"
	groupManagement = "cli-management"
)

// groupRootCommands classifies root's direct children into the help groups,
// called once after all commands are registered. Unclassified commands fall to
// cobra's "Additional Commands" section.
func groupRootCommands(root *cobra.Command) {
	root.AddGroup(
		&cobra.Group{ID: groupDomains, Title: "Lark domains:"},
		&cobra.Group{ID: groupTooling, Title: "Agent tooling:"},
		&cobra.Group{ID: groupManagement, Title: "CLI management:"},
	)
	tooling := map[string]bool{"api": true, "schema": true, "skills": true}
	management := map[string]bool{"auth": true, "config": true, "profile": true, "doctor": true, "update": true}
	for _, c := range root.Commands() {
		if c.GroupID != "" {
			continue
		}
		switch {
		case tooling[c.Name()]:
			c.GroupID = groupTooling
		case management[c.Name()]:
			c.GroupID = groupManagement
		case isLarkDomain(c):
			c.GroupID = groupDomains
		}
	}
}

// isLarkDomain reports whether a root child is a Lark domain (service-sourced or
// shortcut-tagged), not CLI tooling. Mirrors service.PrepareDomainHelp.
func isLarkDomain(c *cobra.Command) bool {
	if src, _ := cmdmeta.SourceOf(c); src == cmdmeta.SourceService {
		return true
	}
	return cmdmeta.Domain(c) != ""
}

// flagDidYouMean is the root FlagErrorFunc (inherited by all subcommands). It
// converts cobra's flag-parse errors into a typed validation envelope: an
// unknown flag gets a focused "did you mean" hint (so agents recover even when
// the typo is semantic, e.g. --query vs --find, where edit distance alone finds
// nothing) and the offending flag in `params`. Other flag errors stay typed
// but generic.
func flagDidYouMean(c *cobra.Command, ferr error) error {
	name, isUnknown := unknownFlagName(ferr)
	if !isUnknown {
		return errs.NewValidationError(errs.SubtypeInvalidArgument, "%s", ferr.Error()).
			WithHint("run `%s --help` for valid flags", c.CommandPath())
	}
	valid := visibleFlagNames(c)
	suggestions := suggest.Closest(name, valid, 3)
	for i := range suggestions {
		suggestions[i] = "--" + suggestions[i]
	}
	hint := fmt.Sprintf("run `%s --help` to see valid flags", c.CommandPath())
	if len(suggestions) > 0 {
		hint = fmt.Sprintf("did you mean %s? (run `%s --help` for all flags)",
			strings.Join(suggestions, ", "), c.CommandPath())
	}
	// The ranked candidates ride on the param as machine-readable Suggestions so
	// an agent can retry without parsing the hint; the hint carries the same
	// candidates as prose. The full valid-flag list stays recoverable via --help.
	return errs.NewValidationError(errs.SubtypeInvalidArgument,
		"unknown flag %q for %q", "--"+name, c.CommandPath()).
		WithParams(errs.InvalidParam{Name: "--" + name, Reason: "unknown flag", Suggestions: suggestions}).
		WithHint("%s", hint)
}

// unknownFlagName extracts the offending long-flag name from cobra's flag-parse
// error text ("unknown flag: --query" → "query"). Returns ok=false for anything
// else (missing argument, invalid value, unknown shorthand) so the caller keeps
// those structured but generic — hallucinated flags are essentially always long.
//
// CONTRACT: this matches cobra's English wording "unknown flag: --" (go.mod
// pins github.com/spf13/cobra). If cobra rewords this or gains i18n the match
// silently fails and unknown flags degrade to a generic flag_error — re-verify
// this prefix when bumping cobra.
func unknownFlagName(err error) (string, bool) {
	const p = "unknown flag: --"
	msg := err.Error()
	i := strings.Index(msg, p)
	if i < 0 {
		return "", false
	}
	rest := msg[i+len(p):]
	if j := strings.IndexAny(rest, " \t"); j >= 0 {
		rest = rest[:j]
	}
	return rest, true
}

// visibleFlagNames lists the non-hidden flag names of c (for suggestions and
// the valid_flags detail).
func visibleFlagNames(c *cobra.Command) []string {
	var names []string
	c.Flags().VisitAll(func(f *pflag.Flag) {
		if !f.Hidden {
			names = append(names, f.Name)
		}
	})
	sort.Strings(names)
	return names
}

// installTipsHelpFunc wraps the default help function to append a TIPS section
// when a command has tips set via cmdutil.SetTips. It also force-shows global
// flags that are normally hidden in single-app mode (currently --profile)
// when rendering the root command's own help, so users discovering the CLI
// still see them at `lark-cli --help`.
func installTipsHelpFunc(root *cobra.Command) {
	defaultHelp := root.HelpFunc()
	root.SetHelpFunc(func(cmd *cobra.Command, args []string) {
		if cmd == root {
			if f := root.PersistentFlags().Lookup("profile"); f != nil && f.Hidden {
				f.Hidden = false
				defer func() { f.Hidden = true }()
			}
		}
		// Domain and method commands compose their agent guidance into Long lazily
		// here (shortcuts attach after service registration); both skip the generic
		// bottom-of-help append below.
		if service.PrepareDomainHelp(cmd, embeddedSkillContent) {
			defaultHelp(cmd, args)
			return
		}
		if service.PrepareMethodHelp(cmd) {
			defaultHelp(cmd, args)
			return
		}
		defaultHelp(cmd, args)
		out := cmd.OutOrStdout()
		if level, ok := cmdutil.GetRisk(cmd); ok {
			fmt.Fprintln(out)
			fmt.Fprintln(out, "Risk:", level)
		}
		tips := cmdutil.GetTips(cmd)
		if len(tips) == 0 {
			return
		}
		fmt.Fprintln(out)
		fmt.Fprintln(out, "Tips:")
		for _, tip := range tips {
			fmt.Fprintf(out, "    • %s\n", tip)
		}
	})
}