mirror of
https://github.com/MichaelMure/git-bug.git
synced 2024-12-15 10:12:06 +03:00
123 lines
3.1 KiB
Go
123 lines
3.1 KiB
Go
package connections
|
|
|
|
import (
|
|
"fmt"
|
|
|
|
"github.com/cheekybits/genny/generic"
|
|
|
|
"github.com/MichaelMure/git-bug/graphql/models"
|
|
)
|
|
|
|
// Name define the name of the connection
|
|
type Name generic.Type
|
|
|
|
// NodeType define the node type handled by this relay connection
|
|
type NodeType generic.Type
|
|
|
|
// EdgeType define the edge type handled by this relay connection
|
|
type EdgeType generic.Type
|
|
|
|
// ConnectionType define the connection type handled by this relay connection
|
|
type ConnectionType generic.Type
|
|
|
|
// NodeTypeEdgeMaker define a function that take a NodeType and an offset and
|
|
// create an Edge.
|
|
type NameEdgeMaker func(value NodeType, offset int) Edge
|
|
|
|
// NameConMaker define a function that create a ConnectionType
|
|
type NameConMaker func(
|
|
edges []*EdgeType,
|
|
nodes []NodeType,
|
|
info *models.PageInfo,
|
|
totalCount int) (*ConnectionType, error)
|
|
|
|
// NameCon will paginate a source according to the input of a relay connection
|
|
func NameCon(source []NodeType, edgeMaker NameEdgeMaker, conMaker NameConMaker, input models.ConnectionInput) (*ConnectionType, error) {
|
|
var nodes []NodeType
|
|
var edges []*EdgeType
|
|
var cursors []string
|
|
var pageInfo = &models.PageInfo{}
|
|
var totalCount = len(source)
|
|
|
|
emptyCon, _ := conMaker(edges, nodes, pageInfo, 0)
|
|
|
|
offset := 0
|
|
|
|
if input.After != nil {
|
|
for i, value := range source {
|
|
edge := edgeMaker(value, i)
|
|
if edge.GetCursor() == *input.After {
|
|
// remove all previous element including the "after" one
|
|
source = source[i+1:]
|
|
offset = i + 1
|
|
pageInfo.HasPreviousPage = true
|
|
break
|
|
}
|
|
}
|
|
}
|
|
|
|
if input.Before != nil {
|
|
for i, value := range source {
|
|
edge := edgeMaker(value, i+offset)
|
|
|
|
if edge.GetCursor() == *input.Before {
|
|
// remove all after element including the "before" one
|
|
pageInfo.HasNextPage = true
|
|
break
|
|
}
|
|
|
|
e := edge.(EdgeType)
|
|
edges = append(edges, &e)
|
|
cursors = append(cursors, edge.GetCursor())
|
|
nodes = append(nodes, value)
|
|
}
|
|
} else {
|
|
edges = make([]*EdgeType, len(source))
|
|
cursors = make([]string, len(source))
|
|
nodes = source
|
|
|
|
for i, value := range source {
|
|
edge := edgeMaker(value, i+offset)
|
|
e := edge.(EdgeType)
|
|
edges[i] = &e
|
|
cursors[i] = edge.GetCursor()
|
|
}
|
|
}
|
|
|
|
if input.First != nil {
|
|
if *input.First < 0 {
|
|
return emptyCon, fmt.Errorf("first less than zero")
|
|
}
|
|
|
|
if len(edges) > *input.First {
|
|
// Slice result to be of length first by removing edges from the end
|
|
edges = edges[:*input.First]
|
|
cursors = cursors[:*input.First]
|
|
nodes = nodes[:*input.First]
|
|
pageInfo.HasNextPage = true
|
|
}
|
|
}
|
|
|
|
if input.Last != nil {
|
|
if *input.Last < 0 {
|
|
return emptyCon, fmt.Errorf("last less than zero")
|
|
}
|
|
|
|
if len(edges) > *input.Last {
|
|
// Slice result to be of length last by removing edges from the start
|
|
edges = edges[len(edges)-*input.Last:]
|
|
cursors = cursors[len(cursors)-*input.Last:]
|
|
nodes = nodes[len(nodes)-*input.Last:]
|
|
pageInfo.HasPreviousPage = true
|
|
}
|
|
}
|
|
|
|
// Fill up pageInfo cursors
|
|
if len(cursors) > 0 {
|
|
pageInfo.StartCursor = cursors[0]
|
|
pageInfo.EndCursor = cursors[len(cursors)-1]
|
|
}
|
|
|
|
return conMaker(edges, nodes, pageInfo, totalCount)
|
|
}
|