package uploader

import (
	"context"
	"fmt"
	"io"
	"sync"
	"time"

	"gitlink.org.cn/cloudream/jcs-pub/client/internal/db"
	"gitlink.org.cn/cloudream/jcs-pub/common/pkgs/ioswitch/exec"
	"gitlink.org.cn/cloudream/jcs-pub/common/pkgs/ioswitch2"
	"gitlink.org.cn/cloudream/jcs-pub/common/pkgs/ioswitch2/ops2"
	"gitlink.org.cn/cloudream/jcs-pub/common/pkgs/ioswitch2/parser"
	"gitlink.org.cn/cloudream/jcs-pub/common/pkgs/publock"
	jcstypes "gitlink.org.cn/cloudream/jcs-pub/common/types"
)

type CreateUploader struct {
	pkg          jcstypes.Package
	targetSpaces []jcstypes.UserSpaceDetail
	copyRoots    []jcstypes.JPath
	uploader     *Uploader
	pubLock      *publock.Mutex
	successes    []db.AddObjectEntry
	lock         sync.Mutex
	commited     bool
}

type CreateUploadResult struct {
	Package jcstypes.Package
	Objects map[string]jcstypes.Object
}

func (u *CreateUploader) Upload(pa jcstypes.JPath, stream io.Reader, opts ...UploadOption) error {
	opt := UploadOption{}
	if len(opts) > 0 {
		opt = opts[0]
	}

	if opt.CreateTime.IsZero() {
		opt.CreateTime = time.Now()
	}

	spaceIDs := make([]jcstypes.UserSpaceID, 0, len(u.targetSpaces))

	ft := ioswitch2.FromTo{}
	fromExec, hd := ioswitch2.NewFromDriver(ioswitch2.RawStream())
	ft.AddFrom(fromExec)
	for i, space := range u.targetSpaces {
		space2 := space
		space2.RecommendHub = nil
		ft.AddTo(ioswitch2.NewToShardStore(space2, ioswitch2.RawStream(), "shardInfo"))
		ft.AddTo(ioswitch2.NewToBaseStore(space2, u.copyRoots[i].ConcatNew(pa)))
		spaceIDs = append(spaceIDs, space2.UserSpace.UserSpaceID)
	}

	plans := exec.NewPlanBuilder()
	err := parser.Parse(ft, plans)
	if err != nil {
		return fmt.Errorf("parsing plan: %w", err)
	}

	exeCtx := exec.NewExecContext()
	exec.SetValueByType(exeCtx, u.uploader.stgPool)
	exec := plans.Execute(exeCtx)
	exec.BeginWrite(io.NopCloser(stream), hd)
	ret, err := exec.Wait(context.TODO())
	if err != nil {
		return fmt.Errorf("executing plan: %w", err)
	}

	u.lock.Lock()
	defer u.lock.Unlock()

	// 记录上传结果
	shardInfo := ret.Get("fileHash").(*ops2.FileInfoValue)
	u.successes = append(u.successes, db.AddObjectEntry{
		Path:         pa.String(),
		Size:         shardInfo.Size,
		FileHash:     shardInfo.Hash,
		CreateTime:   opt.CreateTime,
		UserSpaceIDs: spaceIDs,
	})
	return nil
}

func (u *CreateUploader) Commit() (CreateUploadResult, error) {
	u.lock.Lock()
	defer u.lock.Unlock()

	if u.commited {
		return CreateUploadResult{}, fmt.Errorf("package already commited")
	}
	u.commited = true

	defer u.pubLock.Unlock()

	var addedObjs []jcstypes.Object
	err := u.uploader.db.DoTx(func(tx db.SQLContext) error {
		var err error
		addedObjs, err = u.uploader.db.Object().BatchAdd(tx, u.pkg.PackageID, u.successes)
		return err
	})
	if err != nil {
		return CreateUploadResult{}, fmt.Errorf("adding objects: %w", err)
	}

	ret := CreateUploadResult{
		Package: u.pkg,
		Objects: make(map[string]jcstypes.Object),
	}

	for _, entry := range addedObjs {
		ret.Objects[entry.Path] = entry
	}

	return ret, nil
}

func (u *CreateUploader) Abort() {
	u.lock.Lock()
	defer u.lock.Unlock()

	if u.commited {
		return
	}
	u.commited = true

	u.pubLock.Unlock()

	db2 := u.uploader.db
	db.DoTx10(db2, db2.Package().DeleteComplete, u.pkg.PackageID)
}