aerc/lib/iterator/impl.go

126 lines
2.1 KiB
Go

package iterator
import (
"errors"
"git.sr.ht/~rjarry/aerc/worker/types"
)
// defaultFactory
type defaultFactory struct{}
func (df *defaultFactory) NewIterator(a interface{}) Iterator {
switch data := a.(type) {
case []uint32:
return &defaultUid{data: data, index: len(data)}
case []*types.Thread:
return &defaultThread{data: data, index: len(data)}
}
panic(errors.New("a iterator for this type is not implemented yet"))
}
// defaultUid
type defaultUid struct {
data []uint32
index int
}
func (du *defaultUid) Next() bool {
du.index--
return du.index >= 0
}
func (du *defaultUid) Value() interface{} {
return du.data[du.index]
}
func (du *defaultUid) StartIndex() int {
return len(du.data) - 1
}
func (du *defaultUid) EndIndex() int {
return 0
}
// defaultThread
type defaultThread struct {
data []*types.Thread
index int
}
func (dt *defaultThread) Next() bool {
dt.index--
return dt.index >= 0
}
func (dt *defaultThread) Value() interface{} {
return dt.data[dt.index]
}
func (dt *defaultThread) StartIndex() int {
return len(dt.data) - 1
}
func (dt *defaultThread) EndIndex() int {
return 0
}
// reverseFactory
type reverseFactory struct{}
func (rf *reverseFactory) NewIterator(a interface{}) Iterator {
switch data := a.(type) {
case []uint32:
return &reverseUid{data: data, index: -1}
case []*types.Thread:
return &reverseThread{data: data, index: -1}
}
panic(errors.New("an iterator for this type is not implemented yet"))
}
// reverseUid
type reverseUid struct {
data []uint32
index int
}
func (ru *reverseUid) Next() bool {
ru.index++
return ru.index < len(ru.data)
}
func (ru *reverseUid) Value() interface{} {
return ru.data[ru.index]
}
func (ru *reverseUid) StartIndex() int {
return 0
}
func (ru *reverseUid) EndIndex() int {
return len(ru.data) - 1
}
// reverseThread
type reverseThread struct {
data []*types.Thread
index int
}
func (rt *reverseThread) Next() bool {
rt.index++
return rt.index < len(rt.data)
}
func (rt *reverseThread) Value() interface{} {
return rt.data[rt.index]
}
func (rt *reverseThread) StartIndex() int {
return 0
}
func (rt *reverseThread) EndIndex() int {
return len(rt.data) - 1
}