75 lines
1.9 KiB
Go
75 lines
1.9 KiB
Go
package filetree
|
|
|
|
type TreeCacheKey struct {
|
|
bottomTreeStart, bottomTreeStop, topTreeStart, topTreeStop int
|
|
}
|
|
|
|
type TreeCache struct {
|
|
refTrees []*FileTree
|
|
cache map[TreeCacheKey]*FileTree
|
|
}
|
|
|
|
func (cache *TreeCache) Get(bottomTreeStart, bottomTreeStop, topTreeStart, topTreeStop int) *FileTree {
|
|
key := TreeCacheKey{bottomTreeStart, bottomTreeStop, topTreeStart, topTreeStop}
|
|
if value, exists := cache.cache[key]; exists {
|
|
return value
|
|
} else {
|
|
|
|
}
|
|
value := cache.buildTree(key)
|
|
cache.cache[key] = value
|
|
return value
|
|
}
|
|
|
|
func (cache *TreeCache) buildTree(key TreeCacheKey) *FileTree {
|
|
newTree := StackTreeRange(cache.refTrees, key.bottomTreeStart, key.bottomTreeStop)
|
|
|
|
for idx := key.topTreeStart; idx <= key.topTreeStop; idx++ {
|
|
newTree.Compare(cache.refTrees[idx])
|
|
}
|
|
return newTree
|
|
}
|
|
|
|
func (cache *TreeCache) Build() {
|
|
var bottomTreeStart, bottomTreeStop, topTreeStart, topTreeStop int
|
|
|
|
// case 1: layer compare (top tree SIZE is fixed (BUT floats forward), Bottom tree SIZE changes)
|
|
for selectIdx := 0; selectIdx < len(cache.refTrees); selectIdx++ {
|
|
bottomTreeStart = 0
|
|
topTreeStop = selectIdx
|
|
|
|
if selectIdx == 0 {
|
|
bottomTreeStop = selectIdx
|
|
topTreeStart = selectIdx
|
|
} else {
|
|
bottomTreeStop = selectIdx - 1
|
|
topTreeStart = selectIdx
|
|
}
|
|
|
|
cache.Get(bottomTreeStart, bottomTreeStop, topTreeStart, topTreeStop)
|
|
}
|
|
|
|
// case 2: aggregated compare (bottom tree is ENTIRELY fixed, top tree SIZE changes)
|
|
for selectIdx := 0; selectIdx < len(cache.refTrees); selectIdx++ {
|
|
bottomTreeStart = 0
|
|
topTreeStop = selectIdx
|
|
if selectIdx == 0 {
|
|
bottomTreeStop = selectIdx
|
|
topTreeStart = selectIdx
|
|
} else {
|
|
bottomTreeStop = 0
|
|
topTreeStart = 1
|
|
}
|
|
|
|
cache.Get(bottomTreeStart, bottomTreeStop, topTreeStart, topTreeStop)
|
|
}
|
|
}
|
|
|
|
func NewFileTreeCache(refTrees []*FileTree) TreeCache {
|
|
|
|
return TreeCache{
|
|
refTrees: refTrees,
|
|
cache: make(map[TreeCacheKey]*FileTree),
|
|
}
|
|
}
|