Refactor

 -  Remove stuff I don't use for now.

 -  A single source can now update multiple status items in a single
    tick.

Author: c032

.gitignore

@@ -0,0 +1,2 @@
+/cmd/*/*
+!/cmd/*/*.go

README.md

@@ -2,36 +2,8 @@
 
 My custom status for i3bar.
 
-There's no configuration files, everything is decided at compile time.
-
-I don't even use this anymore, but I also don't want to archive it just
-yet.
-
-## Compile-time requirements
-
-*  Go compiler. See the `go.mod' file to know which version I was using
-   last time I updated this repository.
-
-## Runtime requirements
-
-*  A running instance of MPD. Take a look at the `cmd/dsts' package to
-   know which port number is expected.
-
-## What is being displayed
-
-*  Current date and time in the same format as Skyrim.
-*  Song currently playing in MPD.
-
-## How it works
-
-Each `component' is a function receiving a channel as its only argument.
-Each time a status is sent to that channel, a refresh is triggered.
-
-The main program coordinates all those updates, and sends new messages
-when necessary.
-
-This allows components to each have their own `refresh rate', instead of
-using a single global refresh rate for everything.
+There's runtime no configuration files. The whole point of this, is to
+have a single executable that just works.
 
 ## License
 

cmd/dsts/main.go

@@ -4,36 +4,37 @@
 package main
 
 import (
+	"context"
 	"encoding/json"
+	"errors"
 	"os"
 	"sync"
 
 	"github.com/c032/dsts"
-	"github.com/c032/dsts/mpd"
-	"github.com/c032/dsts/tamrieltime"
+	timesource "github.com/c032/dsts/sources/time"
 )
 
-const (
-	// mpdAddr is the address where MPD is listening in.
-	mpdAddr = ":6600"
+func main() {
+	rootContext := context.Background()
+	ctx, cancel := context.WithCancelCause(rootContext)
 
-	// mpdStatusMaxWidth is the maximum width, in characters, allowed for the
-	// MPD status.
-	mpdStatusMaxWidth = 80
-)
+	srcTime, err := timesource.New(ctx, nil)
+	if err != nil {
+		// Programmer error.
+		panic(err)
+	}
 
-func main() {
-	// Active providers, in the same order that they will be displayed in the
-	// i3bar.
+	sources := []dsts.Source{
+		srcTime,
+	}
+
+	// Active status readers, in the same order that they will be displayed in
+	// the i3bar.
 	//
-	// Providers with a lower index will be displayed somewhere to the left of
-	// providers with a higher index.
-	providers := []dsts.Provider{
-		dsts.Wrap(
-			mpd.Dial(mpdAddr),
-			mpdStatusMaxWidth,
-		),
-		tamrieltime.TamrielTime,
+	// From left to right. Index `0` if leftmost.
+	statusReaders := []dsts.StatusReader{
+		srcTime.StatusUnix,
+		srcTime.StatusDateTime,
 	}
 
 	enc := json.NewEncoder(os.Stdout)
@@ -42,40 +43,72 @@ func main() {
 
 	// tick is only used to notify when the status line must be updated.
 	tick := make(chan struct{})
+	go func(ctx context.Context) {
+		<-ctx.Done()
 
-	// mu prevents multiple goroutines from modifying `i3sts` at the same time.
-	mu := sync.RWMutex{}
-
-	// i3sts is what will be serialized as JSON and printed to standard output.
-	i3sts := make([]dsts.I3Status, len(providers))
-
-	// Run each provider on their own goroutine, coordinate updates to the
-	// i3status line, and trigger a refresh when necessary.
-	for i, p := range providers {
-		ch := make(chan dsts.I3Status)
-
-		// Run the provider, usually forever.
-		go p(ch)
+		close(tick)
+	}(ctx)
 
-		// For each update from the provider, update the current status and
-		// trigger a refresh.
-		go func(i int, p dsts.Provider) {
-			for status := range ch {
-				mu.Lock()
-				i3sts[i] = status
-				mu.Unlock()
+	// `mu` prevents multiple goroutines from modifying `i3sts` at the same
+	// time.
+	mu := sync.RWMutex{}
 
+	// `i3sts` is what will be serialized as JSON and printed to standard
+	// output.
+	i3sts := make([]dsts.I3Status, len(statusReaders))
+
+	// Trigger a refresh each time a source has an update.
+	for _, s := range sources {
+		// `ch` receives a value when there's an update.
+		//
+		// The `Subscribe` method will close `ch`.
+		ch := s.Subscribe(ctx)
+
+		// Start listening for updates in background.
+		//
+		// This goroutine will exit when `ch` is closed.
+		go func(tick chan<- struct{}, ch <-chan struct{}) {
+			for range ch {
 				tick <- struct{}{}
 			}
-		}(i, p)
+		}(tick, ch)
 	}
 
-	// Wait for a refresh to trigger, and update the status line.
+	// Wait for a refresh to trigger. Then read from all status readers and
+	// update the status line.
 	for range tick {
+		if ctx.Err() != nil {
+			// The error will be handled outside the loop.
+			break
+		}
+
 		os.Stdout.Write([]byte{','})
 
-		mu.RLock()
-		_ = enc.Encode(i3sts)
-		mu.RUnlock()
+		mu.Lock()
+
+		for i, readStatus := range statusReaders {
+			i3sts[i] = readStatus()
+		}
+
+		var err error
+		err = enc.Encode(i3sts)
+
+		mu.Unlock()
+
+		if err != nil {
+			cancel(err)
+		}
+	}
+
+	err = ctx.Err()
+	if err != nil {
+		if !errors.Is(err, context.Canceled) {
+			os.Exit(1)
+		}
+
+		cause := context.Cause(ctx)
+		if cause != nil && cause != err {
+			os.Exit(1)
+		}
 	}
 }

color.go

@@ -0,0 +1,33 @@
+package dsts
+
+import (
+	"errors"
+)
+
+var ErrInvalidColor = errors.New("invalid color")
+
+const DefaultStatusColor = "#999999"
+
+func isNumber(c rune) bool {
+	return c >= '0' && c <= '9'
+}
+
+func IsValidColor(color string) bool {
+	if len(color) != len("#000") && len(color) != len("#000000") {
+		return false
+	}
+	if color[0] != '#' {
+		return false
+	}
+
+	for i, c := range color {
+		if i == 0 {
+			continue
+		}
+		if !isNumber(c) {
+			return false
+		}
+	}
+
+	return true
+}

go.mod

@@ -1,3 +1,3 @@
 module github.com/c032/dsts
 
-go 1.12
+go 1.21.6