package spacesyncer

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

	"gitlink.org.cn/cloudream/common/pkgs/logger"
	"gitlink.org.cn/cloudream/common/pkgs/trie"
	"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/parser"
	stgtypes "gitlink.org.cn/cloudream/jcs-pub/common/pkgs/storage/types"
	jcstypes "gitlink.org.cn/cloudream/jcs-pub/common/types"
)

func executeFull(syncer *SpaceSyncer, task *task) {
	log := logger.WithField("Mod", logMod).WithField("TaskID", task.Task.TaskID)

	startTime := time.Now()
	log.Infof("begin full sync task")
	defer func() {
		log.Infof("full sync task finished, time: %v", time.Since(startTime))
	}()

	srcSpace := syncer.spaceMeta.Get(task.Task.SrcUserSpaceID)
	if srcSpace == nil {
		log.Warnf("src space %v not found", task.Task.SrcUserSpaceID)
		return
	}

	dstSpaceIDs := make([]jcstypes.UserSpaceID, len(task.Task.Dests))
	for i := range task.Task.Dests {
		dstSpaceIDs[i] = task.Task.Dests[i].DestUserSpaceID
	}
	dstSpaces := syncer.spaceMeta.GetMany(dstSpaceIDs)

	for i := range dstSpaces {
		if dstSpaces[i] == nil {
			log.Warnf("dst space %v not found", dstSpaceIDs[i])
			return
		}
	}

	srcBase, err := syncer.stgPool.GetBaseStore(srcSpace)
	if err != nil {
		log.Warnf("get src base store: %v", err)
		return
	}

	filter := buildFilter(task)

	srcDirReader := srcBase.ReadDir(task.Task.SrcPath)
	defer srcDirReader.Close()

	srcDirTree := trie.NewTrie[*stgtypes.DirEntry]()
	fileCnt := 0
	for {
		isEOF := false
		ft := ioswitch2.NewFromTo()
		cnt := 0
		for {
			e, err := srcDirReader.Next()
			if err == io.EOF {
				isEOF = true
				break
			}
			if err != nil {
				log.Warnf("read src dir: %v", err)
				return
			}

			rela := e.Path.Clone()
			rela.PopFrontN(task.Task.SrcPath.Len())

			ne := e
			ne.Path = rela.Clone()
			if !filter(ne) {
				continue
			}

			if e.IsDir {
				// 如果是一个目录，则创建对应的Dir节点，且在创建过程中清除掉路径上的Dir信息（仅保留最后一个Dir节点）
				createDirNode(srcDirTree, rela.Comps(), &e)
				continue
			}

			fmt.Printf("rela: %v\n", rela)

			// 如果是一个文件，那么它路径上的目录都可以在写入时一并创建，所以可以清理掉路径上的Dir节点
			removeDirNode(srcDirTree, rela.Comps())
			ft.AddFrom(ioswitch2.NewFromBaseStore(*srcSpace, e.Path))
			for i, dst := range dstSpaces {
				dstPath := task.Task.Dests[i].DestPath.Clone()
				dstPath.Concat(rela)
				ft.AddTo(ioswitch2.NewToBaseStore(*dst, dstPath))
			}
			cnt++
			fileCnt++

			// 每一批转发50个文件
			if cnt > 50 {
				break
			}
		}
		if len(ft.Froms) > 0 {
			planBld := exec.NewPlanBuilder()
			err := parser.Parse(ft, planBld)
			if err != nil {
				log.Warnf("parse fromto to plan: %v", err)
				return
			}

			execCtx := exec.NewWithContext(task.Context)
			exec.SetValueByType(execCtx, syncer.stgPool)
			_, err = planBld.Execute(execCtx).Wait(context.Background())
			if err != nil {
				log.Warnf("execute plan: %v", err)
				return
			}
		}
		if isEOF {
			break
		}
	}

	log.Infof("%v files synced", fileCnt)

	if !task.Task.Options.NoEmptyDirectories {
		dstBases := make([]stgtypes.BaseStore, len(dstSpaces))
		for i := range dstSpaces {
			dstBases[i], err = syncer.stgPool.GetBaseStore(dstSpaces[i])
			if err != nil {
				log.Warnf("get dst base store: %v", err)
				continue
			}
		}

		srcDirTree.Iterate(func(path []string, node *trie.Node[*stgtypes.DirEntry], isWordNode bool) trie.VisitCtrl {
			if node.Value == nil {
				return trie.VisitContinue
			}

			for i, base := range dstBases {
				if base != nil {
					dirPath := task.Task.Dests[i].DestPath.Clone()
					dirPath.Push(path...)
					err := base.Mkdir(dirPath)
					if err != nil {
						log.Warnf("mkdir %v at user space %v: %v", dirPath, dstSpaces[i].String(), err)
					}
				}
			}

			return trie.VisitContinue
		})
	}
}