add custom container sorter

grid.go

@@ -2,13 +2,13 @@ package main
 
 import (
 	"fmt"
-	"sort"
 
 	ui "github.com/gizak/termui"
 )
 
 type Grid struct {
 	cursorPos  uint
+	sortField  string
 	containers map[string]*Container
 }
 
@@ -24,10 +24,18 @@ func (g *Grid) Len() uint {
 // Return sorted list of container IDs
 func (g *Grid) CIDs() []string {
 	var ids []string
-	for id, _ := range g.containers {
-		ids = append(ids, id)
+	var containers []*Container
+
+	for _, c := range g.containers {
+		containers = append(containers, c)
+	}
+
+	sorter := Sorters[g.sortField]
+	sorter(containers).Sort()
+
+	for _, c := range containers {
+		ids = append(ids, c.id)
 	}
-	sort.Strings(ids)
 	return ids
 }
 

main.go

@@ -36,7 +36,7 @@ func main() {
 		panic(err)
 	}
 
-	g := &Grid{0, make(map[string]*Container)}
+	g := &Grid{0, "id", make(map[string]*Container)}
 	for _, c := range getContainers(client) {
 		g.AddContainer(c.ID[:12], parseName(c.Names))
 	}

sort.go

@@ -0,0 +1,45 @@
+package main
+
+import (
+	"sort"
+)
+
+type ContainerSorter interface {
+	sort.Interface
+	Sort()
+}
+
+var Sorters = map[string][]Container{
+	"id":   ByID{},
+	"name": ByName{},
+	"cpu":  ByCPU{},
+	"mem":  ByMem{},
+}
+
+type ByID []*Container
+
+func (a ByID) Len() int           { return len(a) }
+func (a ByID) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+func (a ByID) Less(i, j int) bool { return a[i].id < a[j].id }
+func (a ByID) Sort()              { sort.Sort(a) } // Sort is a convenience method.
+
+type ByName []*Container
+
+func (a ByName) Len() int           { return len(a) }
+func (a ByName) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+func (a ByName) Less(i, j int) bool { return a[i].id < a[j].id }
+func (a ByName) Sort()              { sort.Sort(a) } // Sort is a convenience method.
+
+type ByCPU []*Container
+
+func (a ByCPU) Len() int           { return len(a) }
+func (a ByCPU) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+func (a ByCPU) Less(i, j int) bool { return a[i].reader.CPUUtil < a[j].reader.CPUUtil }
+func (a ByCPU) Sort()              { sort.Sort(a) } // Sort is a convenience method.
+
+type ByMem []*Container
+
+func (a ByMem) Len() int           { return len(a) }
+func (a ByMem) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+func (a ByMem) Less(i, j int) bool { return a[i].reader.MemUsage < a[j].reader.MemUsage }
+func (a ByMem) Sort()              { sort.Sort(a) } // Sort is a convenience method.