// Package llms — bench.go: the mort-flavored facade over majordomo's
// health tracker for the `.failover` Discord commands and the failover
// web UI.
//
// Why a facade (vs exposing health.Tracker directly): the admin surfaces
// want the historical shape — a benched-only list with a manual/auto
// flag. majordomo's tracker treats manual benches (Bench) and automatic
// backoffs identically, so the manual marker is kept mort-side.
package model

import (
	"sync"
	"time"
)

// BenchedModel is one currently-benched model for admin display.
type BenchedModel struct {
	// Model is the "provider/model" target key.
	Model string
	// Until is the end of the bench window.
	Until time.Time
	// ConsecutiveFails is the failure count since the last success.
	ConsecutiveFails int
	// Manual reports the bench was placed by an operator (BenchModel)
	// rather than the automatic failure threshold.
	Manual bool
}

var (
	manualMu      sync.Mutex
	manualBenches = map[string]time.Time{}
)

// ListBenched returns the currently-benched models, manual and automatic,
// from the live health tracker.
func ListBenched() []BenchedModel {
	now := time.Now()
	pruneManual(now)

	var out []BenchedModel
	for _, st := range Health().Snapshot() {
		if !st.Until.After(now) {
			continue
		}
		out = append(out, BenchedModel{
			Model:            st.Key,
			Until:            st.Until,
			ConsecutiveFails: st.ConsecutiveFailures,
			Manual:           isManual(st.Key, st.Until),
		})
	}
	return out
}

// BenchModel manually benches a model spec until the given time. The
// chain executor skips benched targets until the window expires (or
// UnbenchModel clears it).
func BenchModel(model string, until time.Time) {
	Health().Bench(model, until)
	manualMu.Lock()
	manualBenches[model] = until
	manualMu.Unlock()
}

// UnbenchModel clears the bench on a model. Returns true when the model
// was actually benched.
func UnbenchModel(model string) bool {
	now := time.Now()
	wasBenched := Health().BackedOffUntil(model).After(now)
	Health().Unbench(model)
	manualMu.Lock()
	delete(manualBenches, model)
	manualMu.Unlock()
	return wasBenched
}

// isManual reports whether the bench window for key matches a manual
// bench placed via BenchModel. An automatic backoff that outlives the
// manual window supersedes the marker.
func isManual(key string, until time.Time) bool {
	manualMu.Lock()
	defer manualMu.Unlock()
	manualUntil, ok := manualBenches[key]
	return ok && !until.After(manualUntil)
}

// pruneManual drops expired manual markers so the map can't grow
// unbounded across a long uptime.
func pruneManual(now time.Time) {
	manualMu.Lock()
	defer manualMu.Unlock()
	for k, until := range manualBenches {
		if !until.After(now) {
			delete(manualBenches, k)
		}
	}
}