package mount

import (
	"github.com/chrislusf/seaweedfs/weed/filer"
	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
	"github.com/hanwen/go-fuse/v2/fuse"
	"os"
	"syscall"
	"time"
)

func (wfs *WFS) GetAttr(cancel <-chan struct{}, input *fuse.GetAttrIn, out *fuse.AttrOut) (code fuse.Status) {
	if input.NodeId == 1 {
		wfs.setRootAttr(out)
		return fuse.OK
	}

	_, entry, status := wfs.maybeReadEntry(input.NodeId)
	if status != fuse.OK {
		return status
	}
	out.AttrValid = 1
	wfs.setAttrByPbEntry(&out.Attr, input.NodeId, entry)

	return fuse.OK
}

func (wfs *WFS) SetAttr(cancel <-chan struct{}, input *fuse.SetAttrIn, out *fuse.AttrOut) (code fuse.Status) {

	// TODO this is only for directory. Filet setAttr involves open files and truncate to a size

	path, entry, status := wfs.maybeReadEntry(input.NodeId)
	if status != fuse.OK {
		return status
	}

	if mode, ok := input.GetMode(); ok {
		entry.Attributes.FileMode = uint32(mode)
	}

	if uid, ok := input.GetUID(); ok {
		entry.Attributes.Uid = uid
	}

	if gid, ok := input.GetGID(); ok {
		entry.Attributes.Gid = gid
	}

	if mtime, ok := input.GetMTime(); ok {
		entry.Attributes.Mtime = mtime.Unix()
	}

	entry.Attributes.Mtime = time.Now().Unix()
	out.AttrValid = 1
	wfs.setAttrByPbEntry(&out.Attr, input.NodeId, entry)

	return wfs.saveEntry(path, entry)

}

func (wfs *WFS) setRootAttr(out *fuse.AttrOut) {
	now := uint64(time.Now().Unix())
	out.AttrValid = 119
	out.Ino = 1
	setBlksize(&out.Attr, blockSize)
	out.Uid = wfs.option.MountUid
	out.Gid = wfs.option.MountGid
	out.Mtime = now
	out.Ctime = now
	out.Atime = now
	out.Mode = toSystemType(os.ModeDir) | uint32(wfs.option.MountMode)
	out.Nlink = 1
}

func (wfs *WFS) setAttrByPbEntry(out *fuse.Attr, inode uint64, entry *filer_pb.Entry) {
	out.Ino = inode
	out.Size = filer.FileSize(entry)
	out.Blocks = (out.Size + blockSize - 1) / blockSize
	setBlksize(out, blockSize)
	out.Mtime = uint64(entry.Attributes.Mtime)
	out.Ctime = uint64(entry.Attributes.Mtime)
	out.Atime = uint64(entry.Attributes.Mtime)
	out.Mode = toSystemMode(os.FileMode(entry.Attributes.FileMode))
	if entry.HardLinkCounter > 0 {
		out.Nlink = uint32(entry.HardLinkCounter)
	} else {
		out.Nlink = 1
	}
	out.Uid = entry.Attributes.Uid
	out.Gid = entry.Attributes.Gid
}

func (wfs *WFS) setAttrByFilerEntry(out *fuse.Attr, inode uint64, entry *filer.Entry) {
	out.Ino = inode
	out.Size = entry.FileSize
	out.Blocks = (out.Size + blockSize - 1) / blockSize
	setBlksize(out, blockSize)
	out.Atime = uint64(entry.Attr.Mtime.Unix())
	out.Mtime = uint64(entry.Attr.Mtime.Unix())
	out.Ctime = uint64(entry.Attr.Mtime.Unix())
	out.Crtime_ = uint64(entry.Attr.Crtime.Unix())
	out.Mode = toSystemMode(entry.Attr.Mode)
	if entry.HardLinkCounter > 0 {
		out.Nlink = uint32(entry.HardLinkCounter)
	} else {
		out.Nlink = 1
	}
	out.Uid = entry.Attr.Uid
	out.Gid = entry.Attr.Gid
}

func (wfs *WFS) outputPbEntry(out *fuse.EntryOut, inode uint64, entry *filer_pb.Entry) {
	out.NodeId = inode
	out.Generation = 1
	out.EntryValid = 1
	out.AttrValid = 1
	wfs.setAttrByPbEntry(&out.Attr, inode, entry)
}

func (wfs *WFS) outputFilerEntry(out *fuse.EntryOut, inode uint64, entry *filer.Entry) {
	out.NodeId = inode
	out.Generation = 1
	out.EntryValid = 1
	out.AttrValid = 1
	wfs.setAttrByFilerEntry(&out.Attr, inode, entry)
}

func toSystemMode(mode os.FileMode) uint32 {
	return toSystemType(mode) | uint32(mode)
}

func toSystemType(mode os.FileMode) uint32 {
	switch mode & os.ModeType {
	case os.ModeDir:
		return syscall.S_IFDIR
	case os.ModeSymlink:
		return syscall.S_IFLNK
	case os.ModeNamedPipe:
		return syscall.S_IFIFO
	case os.ModeSocket:
		return syscall.S_IFSOCK
	case os.ModeDevice:
		return syscall.S_IFBLK
	case os.ModeCharDevice:
		return syscall.S_IFCHR
	default:
		return syscall.S_IFREG
	}
}

func toFileType(mode uint32) os.FileMode {
	switch mode & (syscall.S_IFMT & 0xffff) {
	case syscall.S_IFDIR:
		return os.ModeDir
	case syscall.S_IFLNK:
		return os.ModeSymlink
	case syscall.S_IFIFO:
		return os.ModeNamedPipe
	case syscall.S_IFSOCK:
		return os.ModeSocket
	case syscall.S_IFBLK:
		return os.ModeDevice
	case syscall.S_IFCHR:
		return os.ModeCharDevice
	default:
		return 0
	}
}

func toFileMode(mode uint32) os.FileMode {
	return toFileType(mode) | os.FileMode(mode&07777)
}