Use log instead of fmt for logging

Also fix up a few errors to lower case

pkg/bearing/bearing.go

@@ -56,7 +56,7 @@ func FromString(s string) (Bearing, error) {
 			return Bearing(i), nil
 		}
 	}
-	return -1, fmt.Errorf("Unknown bearing: %s", s)
+	return -1, fmt.Errorf("unknown bearing: %s", s)
 }
 
 var bearingVectors = []vector.Vector{

pkg/game/atlas.go

@@ -174,7 +174,7 @@ func (a *Atlas) Grow(size int) error {
 	}
 	delta := size - a.Size
 	if delta < 0 {
-		return fmt.Errorf("Cannot shrink an atlas")
+		return fmt.Errorf("cannot shrink an atlas")
 	} else if delta == 0 {
 		return nil
 	}

pkg/game/world.go

@@ -2,6 +2,7 @@ package game
 
 import (
 	"fmt"
+	"log"
 	"math"
 	"math/rand"
 	"strings"
@@ -101,7 +102,7 @@ func (w *World) SpawnRover() (uuid.UUID, error) {
 		return uuid.Nil, err
 	}
 
-	fmt.Printf("Spawned rover at %+v\n", rover.Attributes.Pos)
+	log.Printf("Spawned rover at %+v\n", rover.Attributes.Pos)
 
 	// Append the rover to the list
 	w.Rovers[rover.Id] = rover
@@ -167,7 +168,7 @@ func (w *World) WarpRover(id uuid.UUID, pos vector.Vector) error {
 		if tile, err := w.Atlas.GetTile(pos); err != nil {
 			return fmt.Errorf("coudln't get state of destination rover tile: %s", err)
 		} else if tile == TileRover {
-			return fmt.Errorf("Can't warp rover to occupied tile, check before warping")
+			return fmt.Errorf("can't warp rover to occupied tile, check before warping")
 		} else if err := w.Atlas.SetTile(pos, TileRover); err != nil {
 			return fmt.Errorf("coudln't set rover tile: %s", err)
 		} else if err := w.Atlas.SetTile(i.Attributes.Pos, TileEmpty); err != nil {
@@ -328,7 +329,7 @@ func (w *World) ExecuteCommandQueues() {
 			// Execute the command and clear up if requested
 			if done, err := w.ExecuteCommand(&c, rover); err != nil {
 				w.CommandQueue[rover] = cmds[1:]
-				fmt.Println(err)
+				log.Println(err)
 			} else if done {
 				w.CommandQueue[rover] = cmds[1:]
 			} else {
@@ -349,7 +350,7 @@ func (w *World) ExecuteCommandQueues() {
 
 // ExecuteCommand will execute a single command
 func (w *World) ExecuteCommand(c *Command, rover uuid.UUID) (finished bool, err error) {
-	fmt.Printf("Executing command: %+v\n", *c)
+	log.Printf("Executing command: %+v\n", *c)
 
 	switch c.Command {
 	case "move":
@@ -380,7 +381,7 @@ func PrintTiles(tiles []Tile) {
 	num := int(math.Sqrt(float64(len(tiles))))
 	for j := num - 1; j >= 0; j-- {
 		for i := 0; i < num; i++ {
-			fmt.Printf("%d", tiles[i+num*j])
+			log.Printf("%d", tiles[i+num*j])
 		}
 		fmt.Print("\n")
 	}

pkg/persistence/persistence.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
+	"log"
 	"os"
 	"path"
 )
@@ -38,7 +39,7 @@ func Save(name string, data interface{}) error {
 		}
 	}
 
-	fmt.Printf("Saved %s\n", p)
+	log.Printf("Saved %s\n", p)
 	return nil
 }
 
@@ -48,7 +49,7 @@ func Load(name string, data interface{}) error {
 	// Don't load anything if the file doesn't exist
 	_, err := os.Stat(p)
 	if os.IsNotExist(err) {
-		fmt.Printf("File %s didn't exist, loading with fresh data\n", p)
+		log.Printf("File %s didn't exist, loading with fresh data\n", p)
 		return nil
 	}
 
@@ -56,13 +57,13 @@ func Load(name string, data interface{}) error {
 	if b, err := ioutil.ReadFile(p); err != nil {
 		return err
 	} else if len(b) == 0 {
-		fmt.Printf("File %s was empty, loading with fresh data\n", p)
+		log.Printf("File %s was empty, loading with fresh data\n", p)
 		return nil
 	} else if err := json.Unmarshal(b, data); err != nil {
 		return fmt.Errorf("failed to load file %s error: %s", p, err)
 	}
 
-	fmt.Printf("Loaded %s\n", p)
+	log.Printf("Loaded %s\n", p)
 	return nil
 }
 
@@ -76,7 +77,7 @@ func doAll(f saveLoadFunc, args ...interface{}) error {
 			var ok bool
 			name, ok = a.(string)
 			if !ok {
-				return fmt.Errorf("Incorrect args")
+				return fmt.Errorf("incorrect args")
 			}
 		} else {
 			if err := f(name, a); err != nil {