package strategy

import (
	"strings"
)

const (
	// DefaultHospiceWinRateThreshold retires strains below 15% win rate.
	DefaultHospiceWinRateThreshold = 0.15
	// DefaultHospiceMinAttempts requires enough spread outcomes before auto-retire.
	DefaultHospiceMinAttempts = 5
)

// StrainRetiredBy identifies who sent a strain to hospice.
type StrainRetiredBy string

const (
	StrainRetiredByOperator StrainRetiredBy = "operator"
	StrainRetiredByAI       StrainRetiredBy = "ai"
	StrainRetiredByCourt    StrainRetiredBy = "court"
)

// StrainSpreadStats aggregates epidemiology wins/losses for one spread strain.
type StrainSpreadStats struct {
	StrainID string
	Wins     int
	Losses   int
}

// NormalizeStrainID lowercases #RRGGBB strain identifiers.
func NormalizeStrainID(strain string) string {
	s := strings.TrimSpace(strings.ToLower(strain))
	if s == "" {
		return ""
	}
	if !strings.HasPrefix(s, "#") && len(s) == 6 {
		s = "#" + s
	}
	return s
}

// StrainFromSpreadLane maps a join/spread lane to its stable strain color id.
func StrainFromSpreadLane(lane string) string {
	if s := NormalizeStrainID(SpreadStrainFromJoinLane(lane)); s != "" {
		return s
	}
	return NormalizeStrainID(lane)
}

// LaneInHospice reports whether a spread/join lane's strain is retired.
func LaneInHospice(lane string, hospice map[string]bool) bool {
	if len(hospice) == 0 {
		return false
	}
	return hospice[StrainFromSpreadLane(lane)]
}

// StrainInHospice reports whether a strain id is in the hospice set.
func StrainInHospice(strain string, hospice map[string]bool) bool {
	if len(hospice) == 0 {
		return false
	}
	return hospice[NormalizeStrainID(strain)]
}

// StrainWinRate returns wins / (wins + losses); 1.0 when no attempts recorded.
func StrainWinRate(wins, losses int) float64 {
	total := wins + losses
	if total == 0 {
		return 1.0
	}
	return float64(wins) / float64(total)
}

// ShouldAutoRetireStrain is true when AI hospice policy applies to low performers.
func ShouldAutoRetireStrain(wins, losses int, threshold float64, minAttempts int) bool {
	total := wins + losses
	if total < minAttempts || minAttempts <= 0 {
		return false
	}
	if threshold <= 0 {
		threshold = DefaultHospiceWinRateThreshold
	}
	return StrainWinRate(wins, losses) < threshold
}

// PersonaPrimaryLane returns the first spread lane for a persona preset.
func PersonaPrimaryLane(persona string) string {
	order := PersonaSpreadTierOrder(persona)
	if len(order) == 0 {
		return ""
	}
	return strings.TrimSpace(order[0])
}