package ops2

import (
	"fmt"

	"gitlink.org.cn/cloudream/jcs-pub/common/pkgs/ioswitch/dag"
	"gitlink.org.cn/cloudream/jcs-pub/common/pkgs/ioswitch/exec"
	"gitlink.org.cn/cloudream/jcs-pub/common/pkgs/storage/pool"
	stgtypes "gitlink.org.cn/cloudream/jcs-pub/common/pkgs/storage/types"
	jcstypes "gitlink.org.cn/cloudream/jcs-pub/common/types"
)

func init() {
	exec.UseOp[*GetShardHTTPRequest]()
	exec.UseVarValue[*HTTPRequestValue]()
}

// 旁路Http读取
type GetShardHTTPRequest struct {
	UserSpace jcstypes.UserSpaceDetail
	FileHash  jcstypes.FileHash
	Output    exec.VarID
}

type HTTPRequestValue struct {
	stgtypes.HTTPRequest
}

func (v *HTTPRequestValue) Clone() exec.VarValue {
	return &HTTPRequestValue{
		HTTPRequest: v.HTTPRequest,
	}
}

func (o *GetShardHTTPRequest) Execute(ctx *exec.ExecContext, e *exec.Executor) error {
	stgPool, err := exec.GetValueByType[*pool.Pool](ctx)
	if err != nil {
		return err
	}

	shardStore, err := stgPool.GetShardStore(&o.UserSpace)
	if err != nil {
		return err
	}

	br, ok := shardStore.(stgtypes.HTTPShardRead)
	if !ok {
		return fmt.Errorf("shard store %v not support bypass read", o.UserSpace)
	}

	req, err := br.MakeHTTPReadRequest(o.FileHash)
	if err != nil {
		return err
	}

	e.PutVar(o.Output, &HTTPRequestValue{HTTPRequest: req})
	return nil
}

func (o *GetShardHTTPRequest) String() string {
	return fmt.Sprintf("GetShardHTTPRequest[UserSpace:%v] FileHash: %v, Output: %v", o.UserSpace, o.FileHash, o.Output)
}

// 旁路Http读取
type GetShardHTTPRequestNode struct {
	dag.NodeBase
	UserSpace jcstypes.UserSpaceDetail
	FileHash  jcstypes.FileHash
}

func (b *GraphNodeBuilder) NewGetShardHTTPRequest(userSpace jcstypes.UserSpaceDetail, fileHash jcstypes.FileHash) *GetShardHTTPRequestNode {
	node := &GetShardHTTPRequestNode{
		UserSpace: userSpace,
		FileHash:  fileHash,
	}
	b.AddNode(node)

	node.OutputValues().Init(node, 1)
	return node
}

func (n *GetShardHTTPRequestNode) HTTPRequestVar() dag.ValueOutputSlot {
	return dag.ValueOutputSlot{
		Node:  n,
		Index: 0,
	}
}

func (n *GetShardHTTPRequestNode) GenerateOp() (exec.Op, error) {
	return &GetShardHTTPRequest{
		UserSpace: n.UserSpace,
		FileHash:  n.FileHash,
		Output:    n.HTTPRequestVar().Var().VarID,
	}, nil
}