kenaito-kopsc/internal/registry/registry.go

// Package registry holds kopsc's built-in command registry: platform-neutral
// intents, each with one or more platform-specific variants.
package registry

import (
	"fmt"
	"strings"
)

// Match constrains a Variant to environments. An empty field means "any".
// A Variant with a completely empty Match is a generic fallback.
type Match struct {
	OS         string   // runtime.GOOS
	Arch       string   // runtime.GOARCH
	Distro     string   // exact os-release ID, e.g. "centos"
	DistroLike []string // os-release ID_LIKE ancestry, e.g. "rhel"
	Runtime    string   // container runtime required on PATH, e.g. "docker"
}

// Variant is one concrete implementation of a command.
type Variant struct {
	Match Match
	Argv  []string // program followed by arguments
	Shell bool     // run through the platform shell instead of exec'ing Argv[0]
	// Builtin names an in-process implementation registered with the executor.
	// It is mutually exclusive with Argv and lets kopsc provide commands that
	// have no equivalent system utility (for example on Windows).
	Builtin string
	Note    string // human-readable rationale shown by `kopsc explain`
	// Runtime records which container runtime a builtin should drive when
	// Argv cannot carry it (builtin variants have no argv). Resolution uses
	// Match.Runtime; this field is only informational context for the builtin.
	Runtime string
}

// Command is a platform-neutral intent, e.g. "docker.clearsafe".
type Command struct {
	ID      string // hierarchical, dot-separated: "docker.clearsafe"
	Aliases []string
	Summary string
	Group   string // CLI grouping, e.g. "docker"
	Action  string // what the command does, including its safety contract

	// Usage describes the positional arguments, e.g. "<容器>".
	Usage string
	// MinArgs is the number of positional arguments required before the
	// command is allowed to run. Options before "--" are not counted.
	MinArgs int
	// RequiresYes marks destructive commands: without an explicit --yes they
	// print what they would do and exit non-zero instead of running.
	RequiresYes bool
	// ConfirmBuiltin names a builtin that lists exactly what the command would
	// touch (the containers or images about to be deleted). It runs before the
	// confirmation prompt and for --dry-run; its output is shown to the
	// caller. Empty means "no preview available".
	ConfirmBuiltin string
	// Namespaced marks Kubernetes-aware commands where -n means --namespace
	// (kubectl style) instead of the global --dry-run shorthand.
	Namespaced bool

	Variants []Variant
}

// ValidateArgs reports whether the caller supplied enough positional
// arguments. Everything after "--" counts as positional; before it, arguments
// starting with "-" are treated as options and skipped.
func (c *Command) ValidateArgs(args []string) error {
	if c.MinArgs <= 0 {
		return nil
	}

	count := 0
	positionalOnly := false
	for _, arg := range args {
		switch {
		case positionalOnly:
			count++
		case arg == "--":
			positionalOnly = true
		case strings.HasPrefix(arg, "-") && arg != "-":
			// Option; value-taking options are not distinguishable, so their
			// values may be counted later in the list. This is deliberately a
			// loose check: the underlying tool still validates precisely.
		default:
			count++
		}
	}

	if count < c.MinArgs {
		return &MissingArgsError{Command: c, Got: count}
	}
	return nil
}

// Invocation renders the CLI form of a command, e.g. "kopsc docker logs".
func (c *Command) Invocation() string {
	return "kopsc " + strings.ReplaceAll(c.ID, ".", " ")
}

// MissingArgsError reports too few positional arguments.
type MissingArgsError struct {
	Command *Command
	Got     int
}

func (e *MissingArgsError) Error() string {
	usage := strings.TrimSpace(e.Command.Usage)
	return fmt.Sprintf("命令 %s 缺少参数：需要至少 %d 个（%s），实际 %d 个；用法: %s %s",
		e.Command.ID, e.Command.MinArgs, usage, e.Got, e.Command.Invocation(), usage)
}

// Registry is an ordered set of commands.
type Registry struct {
	Commands []Command
}

// Validate reports structural problems: empty or duplicate identifiers,
// empty aliases, commands without variants and variants without an argv.
func (r *Registry) Validate() error {
	seenIDs := make(map[string]bool)
	seenAliases := make(map[string]string)

	for i, cmd := range r.Commands {
		if strings.TrimSpace(cmd.ID) == "" {
			return fmt.Errorf("command #%d: empty ID", i)
		}
		if seenIDs[cmd.ID] {
			return fmt.Errorf("command #%d: duplicate ID %q", i, cmd.ID)
		}
		seenIDs[cmd.ID] = true

		if strings.TrimSpace(cmd.Summary) == "" {
			return fmt.Errorf("command %q: empty summary", cmd.ID)
		}
		if len(cmd.Variants) == 0 {
			return fmt.Errorf("command %q: no variants", cmd.ID)
		}
		if cmd.MinArgs < 0 {
			return fmt.Errorf("command %q: MinArgs must not be negative", cmd.ID)
		}
		if cmd.MinArgs > 0 && strings.TrimSpace(cmd.Usage) == "" {
			return fmt.Errorf("command %q: MinArgs requires a Usage string", cmd.ID)
		}
		if cmd.RequiresYes && strings.TrimSpace(cmd.Action) == "" {
			return fmt.Errorf("command %q: RequiresYes requires an Action description", cmd.ID)
		}

		for _, alias := range cmd.Aliases {
			if strings.TrimSpace(alias) == "" {
				return fmt.Errorf("command %q: empty alias", cmd.ID)
			}
			if owner, ok := seenAliases[alias]; ok {
				return fmt.Errorf("command %q: alias %q already used by %q", cmd.ID, alias, owner)
			}
			seenAliases[alias] = cmd.ID
		}

		for j, variant := range cmd.Variants {
			if len(variant.Argv) == 0 && variant.Builtin == "" {
				return fmt.Errorf("command %q variant #%d: empty argv and no builtin", cmd.ID, j)
			}
			if len(variant.Argv) > 0 && variant.Builtin != "" {
				return fmt.Errorf("command %q variant #%d: argv and builtin are mutually exclusive", cmd.ID, j)
			}
			if len(variant.Argv) > 0 && strings.TrimSpace(variant.Argv[0]) == "" {
				return fmt.Errorf("command %q variant #%d: empty argv", cmd.ID, j)
			}
			if err := variant.Match.validate(); err != nil {
				return fmt.Errorf("command %q variant #%d: %w", cmd.ID, j, err)
			}
		}
	}

	return nil
}

func (m Match) validate() error {
	for _, field := range m.DistroLike {
		if strings.TrimSpace(field) == "" {
			return fmt.Errorf("empty DistroLike entry")
		}
	}
	return nil
}

// Lookup finds a command by ID or alias.
func (r *Registry) Lookup(idOrAlias string) (*Command, bool) {
	for i := range r.Commands {
		cmd := &r.Commands[i]
		if cmd.ID == idOrAlias {
			return cmd, true
		}
		for _, alias := range cmd.Aliases {
			if alias == idOrAlias {
				return cmd, true
			}
		}
	}
	return nil, false
}

// IDs returns every command ID in registry order.
func (r *Registry) IDs() []string {
	ids := make([]string, 0, len(r.Commands))
	for _, cmd := range r.Commands {
		ids = append(ids, cmd.ID)
	}
	return ids
}