💥 Breaking Change: *EntryとかGetImageとかにした

- GetEntry returns *Entry (not Entry any more)
- Image renamed to GetImage
- Refactoring

cli/amesh.go

@@ -17,7 +17,7 @@ func Amesh(r render.Renderer, geo, mask bool) error {
 	}
 
 	entry := amesh.GetEntry(now)
-	merged, err := entry.Image(geo, mask)
+	merged, err := entry.GetImage(geo, mask)
 	if err != nil {
 		return err
 	}

cli/timelapse.go

@@ -20,7 +20,16 @@ func Timelapse(r render.Renderer, minutes, delay int, loop bool) error {
 
 	fmt.Printf("直近%d分間の降雨画像を取得中", minutes)
 
-	snapshots, err := getSnapshots(time.Duration(minutes) * time.Minute)
+	now, err := getNow()
+	if err != nil {
+		return err
+	}
+
+	start := now.Add(time.Duration(-1*minutes) * time.Minute)
+	entries := amesh.GetEntries(start, now)
+
+	progress := func(i int) { fmt.Print(".") }
+	_, err = entries.GetImages(progress)
 	if err != nil {
 		return err
 	}
@@ -32,40 +41,14 @@ func Timelapse(r render.Renderer, minutes, delay int, loop bool) error {
 		fmt.Print("\033[s\033[H\033[1;32m")
 	}
 
-	length := len(snapshots)
-	for i := 0; true; i++ {
-		if i == length && !loop {
-			break
-		}
-		s := snapshots[i%length]
+	for _, entry := range entries {
 		moveCursorToTop()
-		r.Render(os.Stdout, s.Image)
-		fmt.Println(s.Time.String())
+		r.Render(os.Stdout, entry.Image)
+		fmt.Fprintln(os.Stdout, entry.Time.String())
 		time.Sleep(time.Duration(delay) * time.Millisecond)
 	}
 
 	fmt.Print("\033[0m")
 
 	return nil
 }
-
-func getSnapshots(dur time.Duration) (snapshots []snapshot, err error) {
-
-	now, err := getNow()
-	if err != nil {
-		return nil, err
-	}
-
-	sheets := int((int64(dur) / int64(5*time.Minute))) + 1
-	for i := 0; i < sheets; i++ {
-		t := now.Add(time.Duration(-5*(sheets-i)) * time.Minute)
-		entry := amesh.GetEntry(t)
-		img, err := entry.Image(true, true)
-		if err != nil {
-			return nil, err
-		}
-		snapshots = append(snapshots, snapshot{img, entry.Time})
-		fmt.Print(".")
-	}
-	return snapshots, nil
-}

lib/amesh/entries.go

@@ -0,0 +1,58 @@
+package amesh
+
+import (
+	"image"
+	"image/color/palette"
+	"image/draw"
+	"image/gif"
+	"net/http"
+	"time"
+)
+
+// Entries ...
+type Entries []*Entry
+
+// GetEntries ...
+func GetEntries(start, end time.Time) (entries Entries) {
+	t := truncateTime(start)
+	entries = append(entries, GetEntry(t))
+	for t := t.Add(unit); t.Before(end); t = t.Add(unit) {
+		entries = append(entries, GetEntry(t))
+	}
+	return
+}
+
+// ToImages ...
+func (entries Entries) GetImages(progress func(int), client ...*http.Client) ([]*image.RGBA, error) {
+	images := make([]*image.RGBA, len(entries), len(entries))
+	for i, entry := range entries {
+		img, err := entry.GetImage(true, true, client...)
+		if err != nil {
+			return images, err
+		}
+		images[i] = img
+		if progress != nil {
+			progress(i)
+		}
+	}
+	return images, nil
+}
+
+// ToGif delay == msec
+func (entries Entries) ToGif(delay int, loop bool) (*gif.GIF, error) {
+	dest := &gif.GIF{LoopCount: 5}
+	if loop {
+		dest.LoopCount = 0
+	}
+	images, err := entries.GetImages(nil)
+	if err != nil {
+		return nil, err
+	}
+	for _, img := range images {
+		paletted := image.NewPaletted(img.Bounds(), palette.Plan9)
+		draw.Draw(paletted, paletted.Bounds(), img, img.Bounds().Min, draw.Over)
+		dest.Image = append(dest.Image, paletted)
+		dest.Delay = append(dest.Delay, delay/10) // Because it's 100ths
+	}
+	return dest, err
+}

lib/amesh/entry.go

@@ -26,6 +26,9 @@ const (
 	defaultLocation = "Asia/Tokyo"
 )
 
+// オンメモリ固定画像キャッシュ
+var cache = map[string]image.Image{}
+
 // Entry ...
 type Entry struct {
 	URL  string    `json:"url"`
@@ -35,12 +38,13 @@ type Entry struct {
 	Time time.Time `json:"time"`
 
 	IsRainingFunc func(image.Image) (bool, error)
+	Image         *image.RGBA
 }
 
 // GetEntry ...
-func GetEntry(t time.Time) Entry {
+func GetEntry(t time.Time) *Entry {
 	t = truncateTime(t)
-	return Entry{
+	return &Entry{
 		URL:  AmeshURL,
 		Map:  getMap(),
 		Mesh: getMesh(t),
@@ -66,7 +70,7 @@ func getMesh(t time.Time) string {
 }
 
 // Image fetches image data from URL and merge them if needed.
-func (entry Entry) Image(geo, mask bool, client ...*http.Client) (*image.RGBA, error) {
+func (entry *Entry) GetImage(geo, mask bool, client ...*http.Client) (*image.RGBA, error) {
 
 	// If client not specified, use default HTTP client.
 	// This is because, for example, Google App Engine requires HTTP client with context.
@@ -99,10 +103,14 @@ func (entry Entry) Image(geo, mask bool, client ...*http.Client) (*image.RGBA, e
 		draw.Draw(merged, masklayer.Bounds(), masklayer, image.Point{0, 0}, 0)
 	}
 
+	entry.Image = merged
 	return merged, nil
 }
 
-func (entry Entry) getImageFor(imgurl string, client *http.Client) (image.Image, error) {
+func (entry *Entry) getImageFor(imgurl string, client *http.Client) (image.Image, error) {
+	if cached, ok := cache[imgurl]; ok {
+		return cached, nil
+	}
 	res, err := client.Get(imgurl)
 	if err != nil {
 		return nil, err
@@ -112,9 +120,11 @@ func (entry Entry) getImageFor(imgurl string, client *http.Client) (image.Image,
 		return nil, fmt.Errorf(res.Status)
 	}
 	img, _, err := image.Decode(res.Body)
+	cache[imgurl] = img
 	return img, err
 }
 
+/* FIXME: You ain't gonna need it
 // IsRaining ...
 func (entry *Entry) IsRaining(cliet *http.Client) (bool, error) {
 
@@ -151,3 +161,4 @@ func (entry *Entry) IsRaining(cliet *http.Client) (bool, error) {
 
 	return false, nil
 }
+*/