package aeusadmin

import (
	"context"
	"encoding/json"
	"time"

	"git.nobla.cn/golang/aeus-admin/models"
	"git.nobla.cn/golang/rest"
	"git.nobla.cn/golang/rest/types"
	"gorm.io/gorm"
)

type (
	recorder struct {
		Domain     string            `json:"domain"`
		User       string            `json:"user"`
		Module     string            `json:"module"`
		Table      string            `json:"table"`
		Action     string            `json:"action"`
		PrimaryKey any               `json:"primary_key"`
		Diffs      []*types.DiffAttr `json:"diffs"`
	}
)

type ActivityRecorder struct {
	db           *gorm.DB
	ctx          context.Context
	batchTimeout time.Duration
	BatchSize    int
	ch           chan *models.Activity
}

func (s *ActivityRecorder) onAfterCreate(ctx context.Context, tx *gorm.DB, model any, diff []*types.DiffAttr) {
	v := ctx.Value(rest.RuntimeScopeKey)
	if v == nil {
		return
	}
	runtimeScope, ok := v.(*types.RuntimeScope)
	if !ok {
		return
	}
	data := &models.Activity{}
	data.Uid = runtimeScope.User
	data.Module = runtimeScope.ModuleName
	data.Table = runtimeScope.TableName
	data.Action = types.ScenarioCreate
	if buf, err := json.Marshal(diff); err == nil {
		data.Data = string(buf)
	}
	select {
	case s.ch <- data:
	default:
	}
}

func (s *ActivityRecorder) onAfterUpdate(ctx context.Context, tx *gorm.DB, model any, diff []*types.DiffAttr) {
	v := ctx.Value(rest.RuntimeScopeKey)
	if v == nil {
		return
	}
	runtimeScope, ok := v.(*types.RuntimeScope)
	if !ok {
		return
	}
	data := &models.Activity{}
	data.Uid = runtimeScope.User
	data.Module = runtimeScope.ModuleName
	data.Table = runtimeScope.TableName
	data.Action = types.ScenarioUpdate
	if diff == nil {
		diff = make([]*types.DiffAttr, 0)
	}
	diff = append(diff, &types.DiffAttr{
		Column:   "primary_key",
		NewValue: runtimeScope.PrimaryKeyValue,
	})
	if buf, err := json.Marshal(diff); err == nil {
		data.Data = string(buf)
	}
	select {
	case s.ch <- data:
	default:
	}
}

func (s *ActivityRecorder) onAfterDelete(ctx context.Context, tx *gorm.DB, model any) {
	v := ctx.Value(rest.RuntimeScopeKey)
	if v == nil {
		return
	}
	runtimeScope, ok := v.(*types.RuntimeScope)
	if !ok {
		return
	}
	data := &models.Activity{}
	data.Uid = runtimeScope.User
	data.Module = runtimeScope.ModuleName
	data.Table = runtimeScope.TableName
	data.Action = types.ScenarioDelete
	diff := make([]*types.DiffAttr, 0, 1)
	diff = append(diff, &types.DiffAttr{
		Column:   "primary_key",
		NewValue: runtimeScope.PrimaryKeyValue,
	})
	if buf, err := json.Marshal(diff); err == nil {
		data.Data = string(buf)
	}
	select {
	case s.ch <- data:
	default:
	}
}

func (s *ActivityRecorder) batchWrite(values []*models.Activity) {
	var (
		err error
	)
	if len(values) <= 0 {
		return
	}
	if err = s.db.Create(values).Error; err != nil {
		for _, row := range values {
			s.db.Create(row)
		}
	}
}

func (s *ActivityRecorder) writeLoop() {
	var (
		values []*models.Activity
	)
	timer := time.NewTimer(s.batchTimeout)
	defer func() {
		timer.Stop()
		if len(values) > 0 {
			s.batchWrite(values)
		}
	}()
	for {
		select {
		case <-s.ctx.Done():
			return
		case <-timer.C:
			if len(values) > 0 {
				s.batchWrite(values)
				values = nil
			}
			timer.Reset(s.batchTimeout)
		case msg, ok := <-s.ch:
			if ok {
				values = append(values, msg)
				if len(values) > s.BatchSize {
					s.batchWrite(values)
					values = nil
					timer.Reset(s.batchTimeout)
				}
			}
		}
	}
}

func (s *ActivityRecorder) Recoder(scenes ...string) {
	if len(scenes) == 0 {
		scenes = []string{types.ScenarioCreate, types.ScenarioUpdate, types.ScenarioDelete}
	}
	for _, str := range scenes {
		switch str {
		case types.ScenarioCreate:
			rest.OnAfterCreate(s.onAfterCreate)
		case types.ScenarioUpdate:
			rest.OnAfterUpdate(s.onAfterUpdate)
		case types.ScenarioDelete:
			rest.OnAfterDelete(s.onAfterDelete)
		}
	}
}

func NewActivityRecorder(ctx context.Context, db *gorm.DB) *ActivityRecorder {
	s := &ActivityRecorder{
		db:           db,
		ctx:          ctx,
		batchTimeout: time.Second,
		BatchSize:    50,
		ch:           make(chan *models.Activity, 100),
	}
	go s.writeLoop()
	return s
}