// Package amp provides model mapping functionality for routing Amp CLI requests// to alternative models when the requested model is not available locally.package amp import (	"regexp"	"strings"	"sync" 	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"	"github.com/router-for-me/CLIProxyAPI/v6/internal/util"	log "github.com/sirupsen/logrus") // ModelMapper provides model name mapping/aliasing for Amp CLI requests.// When an Amp request comes in for a model that isn't available locally,// this mapper can redirect it to an alternative model that IS available.type ModelMapper interface {	// MapModel returns the target model name if a mapping exists and the target	// model has available providers. Returns empty string if no mapping applies.	MapModel(requestedModel string) string 	// UpdateMappings refreshes the mapping configuration (for hot-reload).	UpdateMappings(mappings []config.AmpModelMapping)} // DefaultModelMapper implements ModelMapper with thread-safe mapping storage.type DefaultModelMapper struct {	mu       sync.RWMutex	mappings map[string]string // exact: from -> to (normalized lowercase keys)	regexps  []regexMapping    // regex rules evaluated in order} // NewModelMapper creates a new model mapper with the given initial mappings.func NewModelMapper(mappings []config.AmpModelMapping) *DefaultModelMapper {	m := &DefaultModelMapper{		mappings: make(map[string]string),		regexps:  nil,	}	m.UpdateMappings(mappings)	return m} // MapModel checks if a mapping exists for the requested model and if the// target model has available local providers. Returns the mapped model name// or empty string if no valid mapping exists.func (m *DefaultModelMapper) MapModel(requestedModel string) string {	if requestedModel == "" {		return ""	} 	m.mu.RLock()	defer m.mu.RUnlock() 	// Normalize the requested model for lookup	normalizedRequest := strings.ToLower(strings.TrimSpace(requestedModel)) 	// Check for direct mapping	targetModel, exists := m.mappings[normalizedRequest]	if !exists {		// Try regex mappings in order		base, _ := util.NormalizeThinkingModel(requestedModel)		for _, rm := range m.regexps {			if rm.re.MatchString(requestedModel) || (base != "" && rm.re.MatchString(base)) {				targetModel = rm.to				exists = true				break			}		}		if !exists {			return ""		}	} 	// Verify target model has available providers	normalizedTarget, _ := util.NormalizeThinkingModel(targetModel)	providers := util.GetProviderName(normalizedTarget)	if len(providers) == 0 {		log.Debugf("amp model mapping: target model %s has no available providers, skipping mapping", targetModel)		return ""	} 	// Note: Detailed routing log is handled by logAmpRouting in fallback_handlers.go	return targetModel} // UpdateMappings refreshes the mapping configuration from config.// This is called during initialization and on config hot-reload.func (m *DefaultModelMapper) UpdateMappings(mappings []config.AmpModelMapping) {	m.mu.Lock()	defer m.mu.Unlock() 	// Clear and rebuild mappings	m.mappings = make(map[string]string, len(mappings))	m.regexps = make([]regexMapping, 0, len(mappings)) 	for _, mapping := range mappings {		from := strings.TrimSpace(mapping.From)		to := strings.TrimSpace(mapping.To) 		if from == "" || to == "" {			log.Warnf("amp model mapping: skipping invalid mapping (from=%q, to=%q)", from, to)			continue		} 		if mapping.Regex {			// Compile case-insensitive regex; wrap with (?i) to match behavior of exact lookups			pattern := "(?i)" + from			re, err := regexp.Compile(pattern)			if err != nil {				log.Warnf("amp model mapping: invalid regex %q: %v", from, err)				continue			}			m.regexps = append(m.regexps, regexMapping{re: re, to: to})			log.Debugf("amp model regex mapping registered: /%s/ -> %s", from, to)		} else {			// Store with normalized lowercase key for case-insensitive lookup			normalizedFrom := strings.ToLower(from)			m.mappings[normalizedFrom] = to			log.Debugf("amp model mapping registered: %s -> %s", from, to)		}	} 	if len(m.mappings) > 0 {		log.Infof("amp model mapping: loaded %d mapping(s)", len(m.mappings))	}	if n := len(m.regexps); n > 0 {		log.Infof("amp model mapping: loaded %d regex mapping(s)", n)	}} // GetMappings returns a copy of current mappings (for debugging/status).func (m *DefaultModelMapper) GetMappings() map[string]string {	m.mu.RLock()	defer m.mu.RUnlock() 	result := make(map[string]string, len(m.mappings))	for k, v := range m.mappings {		result[k] = v	}	return result} type regexMapping struct {	re *regexp.Regexp	to string}