// 织忆 MemoryWeave — 触发器执行器
package selfoptimize

import (
	"log"
	"sync"
	"time"
)

// ─── 触发器执行器 ──────────────────────────────────────

// TriggerExecutor 8 类触发器自动执行循环
type TriggerExecutor struct {
	mu            sync.RWMutex
	triggers      []*TriggerDef
	checkInterval time.Duration
	eventBus      TriggerEventBus
}

// TriggerDef 触发器定义
type TriggerDef struct {
	ID          string        `json:"id"`
	Type        TriggerExType `json:"type"`
	Condition   interface{}   `json:"condition"`
	Action      string        `json:"action"`       // 触发的流水线任务类型
	LastFired   time.Time     `json:"last_fired"`
	Cooldown    time.Duration `json:"cooldown"`      // 冷却时间
	Enabled     bool          `json:"enabled"`
	FireCount   int           `json:"fire_count"`
}

type TriggerExType string

const (
	TCommitCount TriggerExType = "commit_count"    // 新增 N 条
	TTimeSince   TriggerExType = "time_since"      // 距上次 N 小时
	TRecallMiss  TriggerExType = "recall_miss"     // 连续 N 次 miss
	TQualityDrop TriggerExType = "quality_drop"    // quality < threshold
	TGapDetected TriggerExType = "gap_detected"    // 新缺口
	TConflict    TriggerExType = "conflict_pending" // 待解决冲突
	TVValueLow   TriggerExType = "v_value_low"     // V 值过低
	TDecayCritical TriggerExType = "decay_critical" // 衰减临界
)

type TriggerEventBus interface {
	OnTrigger(trigger *TriggerDef)
}

// 全局触发器状态
var Executor = &TriggerExecutor{
	triggers:      makeTriggers(),
	checkInterval: 5 * time.Minute,
}

func makeTriggers() []*TriggerDef {
	return []*TriggerDef{
		{ID: "t1", Type: TCommitCount, Condition: 50, Action: "consolidate", Cooldown: 24 * time.Hour, Enabled: true},
		{ID: "t2", Type: TTimeSince, Condition: 48.0, Action: "consolidate", Cooldown: 24 * time.Hour, Enabled: true},
		{ID: "t3", Type: TRecallMiss, Condition: 3, Action: "gap_classify", Cooldown: 30 * time.Minute, Enabled: true},
		{ID: "t4", Type: TQualityDrop, Condition: 0.3, Action: "deprecate_review", Cooldown: 1 * time.Hour, Enabled: true},
		{ID: "t5", Type: TGapDetected, Condition: true, Action: "gap_fill", Cooldown: 5 * time.Minute, Enabled: true},
		{ID: "t6", Type: TConflict, Condition: 3, Action: "conflict_muchen", Cooldown: 10 * time.Minute, Enabled: true},
		{ID: "t7", Type: TVValueLow, Condition: 0.2, Action: "mem_review", Cooldown: 12 * time.Hour, Enabled: true},
		{ID: "t8", Type: TDecayCritical, Condition: 0.1, Action: "archive_or_boost", Cooldown: 6 * time.Hour, Enabled: true},
	}
}

// Start 启动触发器检查循环
func (te *TriggerExecutor) Start(flow *Pipeline) {
	if te.eventBus == nil {
		te.eventBus = &defaultEventBus{flow: flow}
	}
	go te.loop()
	log.Println("[executor] 触发器执行器启动 (8 triggers)")
}

func (te *TriggerExecutor) loop() {
	ticker := time.NewTicker(te.checkInterval)
	defer ticker.Stop()

	for range ticker.C {
		te.checkAll()
	}
}

func (te *TriggerExecutor) checkAll() {
	te.mu.RLock()
	triggers := make([]*TriggerDef, len(te.triggers))
	copy(triggers, te.triggers)
	te.mu.RUnlock()

	metrics := Dash.Metrics()

	for _, t := range triggers {
		if !t.Enabled {
			continue
		}
		if time.Since(t.LastFired) < t.Cooldown {
			continue
		}
		if te.evaluate(t, metrics) {
			t.LastFired = time.Now()
			t.FireCount++
			te.eventBus.OnTrigger(t)
			log.Printf("[executor] trigger %s fired (count=%d)", t.ID, t.FireCount)
		}
	}
}

func (te *TriggerExecutor) evaluate(t *TriggerDef, metrics map[string]float64) bool {
	switch t.Type {
	case TCommitCount:
		// 需要 commit 计数（从 LanceDB stats 获取）
		return false // 待集成
	case TTimeSince:
		hours := time.Since(t.LastFired).Hours()
		threshold, _ := t.Condition.(float64)
		return hours >= threshold
	case TRecallMiss:
		// 检查最近的 miss 计数
		rate, ok := metrics["recall_hit_rate"]
		return ok && rate > 0 && t.LastFired.IsZero()
	case TQualityDrop:
		threshold, _ := t.Condition.(float64)
		return metrics["recall_usefulness_rate"] < threshold
	case TGapDetected:
		return metrics["gap_closure_rate"] < 0.5
	case TConflict:
		return metrics["auto_resolve_rate"] < 0.5
	case TVValueLow:
		threshold, _ := t.Condition.(float64)
		return metrics["recall_usefulness_rate"] < threshold
	case TDecayCritical:
		return metrics["deprecated_per_day"] > 5
	}
	return false
}

// Fire 手动触发
func (te *TriggerExecutor) Fire(triggerID string) bool {
	te.mu.RLock()
	defer te.mu.RUnlock()

	for _, t := range te.triggers {
		if t.ID == triggerID {
			t.LastFired = time.Now()
			t.FireCount++
			te.eventBus.OnTrigger(t)
			return true
		}
	}
	return false
}

// List 返回所有触发器状态
func (te *TriggerExecutor) List() []*TriggerDef {
	te.mu.RLock()
	defer te.mu.RUnlock()
	result := make([]*TriggerDef, len(te.triggers))
	copy(result, te.triggers)
	return result
}

// defaultEventBus 默认实现：触发 → 入队到流水线
type defaultEventBus struct {
	flow *Pipeline
}

func (eb *defaultEventBus) OnTrigger(t *TriggerDef) {
	if eb.flow != nil {
		eb.flow.Enqueue(t.Action, map[string]string{
			"trigger_id": t.ID,
			"action":     t.Action,
		})
	}
}