package processing

import "strings"

// Analytics provider mode labels (must match aiprovider.AnalyticsMode contract).
const (
	AIProviderInternal = "internal"
	AIProviderCustom   = "custom"
	AIProviderUnknown  = "unknown"
)

// ProviderLabeler optionally reports the analytics mode for a Completer.
type ProviderLabeler interface {
	ProviderModeLabel() string
}

// CompleterProviderMode returns the analytics label for a Completer.
func CompleterProviderMode(c Completer) string {
	if c == nil {
		return AIProviderUnknown
	}
	if p, ok := c.(ProviderLabeler); ok {
		return normalizeProviderMode(p.ProviderModeLabel())
	}
	// Historical env-backed OpenAI clients without an explicit label.
	return AIProviderInternal
}

// EngineProviderMode returns Engine.ProviderMode when set, else CompleterProviderMode.
func (e *Engine) EngineProviderMode() string {
	if e == nil {
		return AIProviderUnknown
	}
	if label := strings.TrimSpace(e.ProviderMode); label != "" {
		return normalizeProviderMode(label)
	}
	return CompleterProviderMode(e.Completer)
}

func normalizeProviderMode(label string) string {
	m := strings.ToLower(strings.TrimSpace(label))
	switch {
	case m == "" || m == AIProviderUnknown:
		return AIProviderUnknown
	case m == AIProviderInternal:
		return AIProviderInternal
	case m == AIProviderCustom:
		return AIProviderCustom
	case strings.HasPrefix(m, "popular:"):
		name := strings.TrimSpace(strings.TrimPrefix(m, "popular:"))
		if name == "" {
			name = "unknown"
		}
		return "popular:" + name
	default:
		return AIProviderUnknown
	}
}

// isUnknownProviderMode reports empty or the sentinel "unknown" analytics label.
func isUnknownProviderMode(label string) bool {
	m := strings.ToLower(strings.TrimSpace(label))
	return m == "" || m == AIProviderUnknown
}

// preferKnownProviderMode returns the first non-unknown label, else unknown.
func preferKnownProviderMode(candidates ...string) string {
	for _, c := range candidates {
		if !isUnknownProviderMode(c) {
			return normalizeProviderMode(c)
		}
	}
	return AIProviderUnknown
}

func lastResultAIProviderMode(r *StepResult) string {
	if r == nil {
		return ""
	}
	return r.AIProviderMode
}