feat: address TODOs and write README.md

internal/command/command.go

@@ -4,7 +4,6 @@ import (
 	"cmp"
 	"context"
 	"fmt"
-	"net/url"
 	"os"
 	"os/signal"
 	"slices"
@@ -17,7 +16,6 @@ import (
 	"github.com/StevanFreeborn/gator/internal/rss"
 	"github.com/StevanFreeborn/gator/internal/state"
 	"github.com/google/uuid"
-	"golang.org/x/term"
 )
 
 type Command struct {
@@ -192,30 +190,13 @@ func aggCommand() *Command {
 		ctx, cancel := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
 		defer cancel()
 
-		oldState, err := term.MakeRaw(int(os.Stdin.Fd()))
+		restore, err := enableKeypressExit(cancel)
 
 		if err != nil {
-			return fmt.Errorf("Failed to enable raw mode: %v", err)
+			return err
 		}
 
-		defer term.Restore(int(os.Stdin.Fd()), oldState)
-
-		go func() {
-			buf := make([]byte, 1)
-
-			for {
-				n, err := os.Stdin.Read(buf)
-
-				if err != nil || n == 0 {
-					return
-				}
-
-				if buf[0] == 'q' || buf[0] == 'Q' || buf[0] == 3 {
-					cancel()
-					return
-				}
-			}
-		}()
+		defer restore()
 
 		ticker := time.NewTicker(validDuration)
 		defer ticker.Stop()
@@ -246,21 +227,27 @@ func addFeedCommand() *Command {
 		feedName := s.Arguments[0]
 		feedUrl := s.Arguments[1]
 
-		validatedFeedUrl, err := url.Parse(feedUrl)
-
 		if strings.TrimSpace(feedName) == "" {
 			return fmt.Errorf("Feed name cannot be empty")
 		}
 
+		canonicalFeedUrl, err := normalizeFeedURL(feedUrl)
+
 		if err != nil {
 			return fmt.Errorf("Feed url '%s' is not a valid url", feedUrl)
 		}
 
+		_, err = s.Database.GetFeedByUrl(context.Background(), canonicalFeedUrl)
+
+		if err == nil {
+			return fmt.Errorf("Feed with url '%s' already exists; use 'follow <name>' to follow it", canonicalFeedUrl)
+		}
+
 		createFeedParams := database.CreateFeedParams{
 			ID:        uuid.New(),
 			UserID:    currentUser.ID,
 			Name:      feedName,
-			Url:       validatedFeedUrl.String(),
+			Url:       canonicalFeedUrl,
 			CreatedAt: time.Now(),
 			UpdatedAt: time.Now(),
 		}
@@ -325,12 +312,12 @@ func followCommand() *Command {
 			return fmt.Errorf("Did not receive expected url argument")
 		}
 
-		urlForFeedToFollow := s.Arguments[0]
+		feedIdentifier := s.Arguments[0]
 
-		feed, err := s.Database.GetFeedByUrl(context.Background(), urlForFeedToFollow)
+		feed, err := resolveFeedByNameOrURL(s, feedIdentifier)
 
 		if err != nil {
-			return fmt.Errorf("Unable to find feed with url '%s'", urlForFeedToFollow)
+			return err
 		}
 
 		createFollowParams := database.CreateFollowParams{
@@ -375,12 +362,12 @@ func unfollowCommand() *Command {
 			return fmt.Errorf("Did not receive expected feed url argument")
 		}
 
-		feedUrl := s.Arguments[0]
+		feedIdentifier := s.Arguments[0]
 
-		feed, err := s.Database.GetFeedByUrl(context.Background(), feedUrl)
+		feed, err := resolveFeedByNameOrURL(s, feedIdentifier)
 
 		if err != nil {
-			return fmt.Errorf("Unable to find feed with url '%s'", feedUrl)
+			return err
 		}
 
 		deleteFollowParams := database.DeleteFollowForUserParams{