package input

import (
	"fmt"
	"strings"
)

// Tentacle bindings are runtime registrations, never persisted core overrides.
// The native input owner arbitrates them again whenever core settings change.
func ValidateTentacleBindings(bindings []BindingOverride) error {
	if len(bindings) > 16*32*4 {
		return fmt.Errorf("too many tentacle bindings")
	}
	for _, binding := range bindings {
		if !strings.HasPrefix(string(binding.Command), "tentacle/") || len(binding.Command) > 400 ||
			(binding.Layout != DesktopKeyboardLayout && binding.Layout != LaptopKeyboardLayout) ||
			(binding.Scope != "global" && binding.Scope != "browse") || len(binding.Keys) != 1 {
			return fmt.Errorf("invalid tentacle binding")
		}
		if _, err := ParseCommandChord(binding.Keys[0]); err != nil {
			return err
		}
	}
	return nil
}

// MergeTentacleBindings preserves core bindings and registration order. A
// conflicting suggestion stays unbound. Callers validate both inputs first.
func MergeTentacleBindings(core, suggestions []BindingOverride) []BindingOverride {
	result := CloneBindingOverrides(core)
	for _, layout := range []KeyboardLayout{DesktopKeyboardLayout, LaptopKeyboardLayout} {
		occupied, _ := ResolveCommandBindings(layout, true, core)
		for _, suggestion := range suggestions {
			if suggestion.Layout != layout {
				continue
			}
			chord, _ := ParseCommandChord(suggestion.Keys[0])
			if occupied[chord] != "" {
				continue
			}
			occupied[chord] = suggestion.Command
			result = append(result, CloneBindingOverrides([]BindingOverride{suggestion})[0])
		}
	}
	return result
}