package mdbc

import (
	"context"
	"errors"
	"time"

	"go.mongodb.org/mongo-driver/mongo"
)

type DropScope struct {
	scope *Scope
	cw    *ctxWrap
	err   error
}

// SetContext 设置上下文
func (ds *DropScope) SetContext(ctx context.Context) *DropScope {
	if ds.cw == nil {
		ds.cw = &ctxWrap{}
	}
	ds.cw.ctx = ctx
	return ds
}

func (ds *DropScope) preCheck() {
	var breakerTTL time.Duration
	if ds.scope.breaker == nil {
		breakerTTL = defaultBreakerTime
	} else if ds.scope.breaker.ttl == 0 {
		breakerTTL = defaultBreakerTime
	} else {
		breakerTTL = ds.scope.breaker.ttl
	}
	if ds.cw == nil {
		ds.cw = &ctxWrap{}
	}
	if ds.cw.ctx == nil {
		ds.cw.ctx, ds.cw.cancel = context.WithTimeout(context.Background(), breakerTTL)
	}
}

func (ds *DropScope) assertErr() {
	if ds.err == nil {
		return
	}
	if errors.Is(ds.err, context.DeadlineExceeded) {
		ds.err = &ErrRequestBroken
		return
	}
	err, ok := ds.err.(mongo.CommandError)
	if !ok {
		return
	}
	if err.HasErrorMessage(context.DeadlineExceeded.Error()) {
		ds.err = &ErrRequestBroken
		return
	}
}

func (ds *DropScope) doString() string {
	return "drop()"
}

func (ds *DropScope) debug() {
	if !ds.scope.debug {
		return
	}

	debugger := &Debugger{
		collection: ds.scope.tableName,
		execT:      ds.scope.execT,
		action:     ds,
	}
	debugger.String()
}

func (ds *DropScope) getContext() context.Context {
	return ds.cw.ctx
}

func (ds *DropScope) doClear() {
	if ds.cw != nil && ds.cw.cancel != nil {
		ds.cw.cancel()
	}
	ds.scope.execT = 0
	ds.scope.debug = false
}

// Do 删除Model绑定的集合
func (ds *DropScope) Do() error {
	defer ds.doClear()
	ds.preCheck()

	defer ds.assertErr()
	var starTime time.Time
	if ds.scope.debug {
		starTime = time.Now()
	}
	ds.err = db.Collection(ds.scope.tableName).Drop(ds.getContext())
	if ds.scope.debug {
		ds.scope.execT = time.Since(starTime)
		ds.debug()
	}
	if ds.err != nil {
		return ds.err
	}

	return nil
}