Read podcast list from saved file and merge new entries. Add daysAgo() selector.

Remember length of podcast episodes so we know if we need to download it again.

.gitignore

@@ -1,2 +1,3 @@
 rssd.conf
 output.conf
+*.mp3

main.go

@@ -3,6 +3,7 @@ package main
 import (
 	"log"
 	"os"
+	"strconv"
 	"time"
 
 	"github.com/BurntSushi/toml"
@@ -15,10 +16,11 @@ type Config struct {
 
 type Item struct {
 	Title, Description, Url, Filename string
+	Length int
 }
 
 type Podcast struct {
-	Title, Description string
+	Title, Description, Url string
 	Items []Item
 }
 
@@ -26,32 +28,79 @@ type pcList struct {
 	Podcasts []Podcast
 }
 
+func newpcList(confs ...string) (ret *pcList) {
+	ret = &pcList{}
+	ret.Podcasts = make([]Podcast,0)
+	if len(confs) > 0 {
+		if _, err := toml.DecodeFile("output.conf", &ret); err != nil {
+			log.Print("Error reading podcast list:",err)
+		}
+	}
+	return
+}
+
+func (p *pcList) Find(x *Podcast) (int, bool) {
+	for i,y := range p.Podcasts {
+		if y.Title == x.Title {
+			return i, true
+		}
+	}
+	return 0, false
+}
+
 func (p *pcList) Add(x *Podcast) {
-	(*p).Podcasts = append((*p).Podcasts,*x)
+	if x == nil {
+		return
+	}
+	if i,ok := p.Find(x); ok == true {
+		log.Print("     Existing podcast")
+		p.Podcasts[i].Merge(x)
+	} else {
+		log.Print("     New podcast")
+		p.Podcasts = append((*p).Podcasts,*x)
+	}
 }
 
-type Db struct {
-	Podcasts []Podcast
+func (p *Podcast) Merge(x *Podcast) {
+	for _,item := range x.Items {
+		if !p.Has(item) {
+			log.Print("        Appending '",item.Title,"'")
+			p.Items = append(p.Items,item)
+		}
+	}
 }
 
-type Selector func(*gofeed.Item) bool
-
-func Any(ss []Selector, i *gofeed.Item) bool {
-	for _, s := range ss {
-		if s(i) {
+func (p *Podcast) Has(i Item) bool {
+	for _,x := range p.Items {
+		if x.Title == i.Title {
 			return true
 		}
 	}
 	return false
 }
 
-func All(ss []Selector, i *gofeed.Item) bool {
-	for _, s := range ss {
-		if !s(i) {
-			return false
+type Selector func(*gofeed.Item) bool
+
+func AllSelectors(ss ...Selector) Selector {
+	return func(i *gofeed.Item) bool {
+		for _, s := range ss {
+			if !s(i) {
+				return false
+			}
 		}
+		return true
+	}
+}
+
+func AnySelector(ss ...Selector) Selector {
+	return func(i *gofeed.Item) bool {
+		for _, s := range ss {
+			if s(i) {
+				return true
+			}
+		}
+		return false
 	}
-	return true
 }
 
 func newerThan(t time.Time) Selector {
@@ -63,20 +112,46 @@ func newerThan(t time.Time) Selector {
 	}
 }
 
-func readFeed(url string,ss ...Selector) *Podcast {
+func daysAgo(x int) Selector {
+	d := time.Now()
+	return newerThan(time.Date(d.Year(),d.Month(),d.Day()-x,0,0,0,0,time.Local))
+}
+
+func toPodcast(sel Selector, url string, feed *gofeed.Feed) (ret *Podcast) {
+	ret = &Podcast{
+		Title: feed.Title,
+		Description: feed.Description,
+		Url: url,
+		Items: []Item{},
+	}
+	for _, i := range feed.Items {
+		if sel(i) {
+			it := Item{
+				Title: i.Title,
+				Description: i.Description,
+			}
+			for _, n := range i.Enclosures {
+				if n.Type == "audio/mpeg" {
+					it.Url = n.URL
+					if l, err := strconv.Atoi(n.Length); err == nil {
+						it.Length = l
+					}
+				}
+			}
+			ret.Items = append(ret.Items,it)
+		}
+	}
+	return
+}
+
+func readFeed(url string,sel Selector) *Podcast {
 	fp := gofeed.NewParser()
 	feed, err := fp.ParseURL(url)
 	if err != nil {
-		log.Fatal(err)
+		log.Print(err)
+		return nil
 	}
-	pc := Podcast{ feed.Title, feed.Description, []Item{} }
-	for _, i := range feed.Items {
-		if All(ss,i) {
-			it := Item{ Title: i.Title, Description: i.Description }
-			pc.Items = append(pc.Items,it)
-		}
-	}
-	return &pc
+	return toPodcast(sel,url,feed)
 }
 
 func main() {
@@ -86,15 +161,12 @@ func main() {
 	if _, err := toml.DecodeFile("rssd.conf", &conf); err != nil {
 		log.Fatal("Error reading config file:",err)
 	}
-	pl := &pcList{}
-	pl.Podcasts = make([]Podcast,0)
-
-	d := time.Now()
-	lastMonth := newerThan(time.Date(d.Year(),d.Month()-1,d.Day(),0,0,0,0,time.Local))
+	pl := newpcList("output.conf")
 
+	sel := daysAgo(60)
 	for _,url := range conf.Urls {
 		log.Print("  -> ",url)
-		pl.Add(readFeed(url,lastMonth))
+		pl.Add(readFeed(url,sel))
 	}
 	of,err := os.Create("output.conf")
 	if err != nil {