Updater: add --dry-run parameter

- go fmt pass

3 files changed, 156 insertions, 127 deletions

diff --git a/tools/updater/download.go b/tools/updater/download.go
index b89703b..2adfe41 100644
--- a/tools/updater/download.go
+++ b/tools/updater/download.go
@@ -1,62 +1,90 @@
 package main
 
 import (
-    "fmt"
-    "strings"
-    "os"
-    "io"
-    "net/http"
-    "path/filepath"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"path/filepath"
+	"strings"
 )
 
+func Min(x, y int64) int64 {
+	if x < y {
+		return x
+	}
+	return y
+}
+
+func Max(x, y int64) int64 {
+	if x > y {
+		return x
+	}
+	return y
+}
+
 // WriteCounter counts the number of bytes written to it
 type WriteCounter struct {
-    Filepath string
-    Total uint64
+	ContentLength int64
+	BytesWritten  uint64
+
+	Step int64
+}
+
+func NewWriteCounter(contentLength int64) *WriteCounter {
+	ptr := new(WriteCounter)
+	ptr.ContentLength = contentLength
+	ptr.Step = Max(contentLength/20, 1)
+
+	return ptr
 }
 
 func (wc *WriteCounter) Write(p []byte) (int, error) {
-    n := len(p)
-    wc.Total += uint64(n)
-    wc.PrintProgress()
-    return n, nil
+	n := len(p)
+	wc.BytesWritten += uint64(n)
+	wc.PrintProgress()
+	return n, nil
 }
 
 func (wc *WriteCounter) PrintProgress() {
-    // clear the line by using a character return to go back to the start of the
-    // line and remove the remaining characters
-    fmt.Printf("\r%s", strings.Repeat(" ", 35))
-    fmt.Printf("\r[%s]... %d bytes complete", wc.Filepath, wc.Total)
+	// clear the line by using a character return to go back to the start of the
+	// line and remove the remaining characters
+	fmt.Printf("\r%s", strings.Repeat(" ", 35))
+
+	// steps can be at most 20 -> get the minimum of (n_steps) and 20
+	steps := int(Min(int64(wc.BytesWritten)/wc.Step, 20))
+
+	fmt.Printf("\r[%s%s] %d/%d bytes complete", strings.Repeat("#", steps), strings.Repeat(" ", 20-steps), wc.BytesWritten, wc.ContentLength)
 }
 
 func downloadFile(path string, url string) error {
-    // make sure dir exists
-    os.MkdirAll(filepath.Dir(path), 0777)
-
-    // create .part file
-    output, err := os.Create(path + ".part")
-    if err != nil {
-        return err
-    }
-    defer output.Close()
-
-    // get data
-    response, err := http.Get(url)
-    if err != nil {
-        return err
-    }
-    defer response.Body.Close()
-
-    // create progress reporter
-    counter := &WriteCounter{path, 0}
-    _, err = io.Copy(output, io.TeeReader(response.Body, counter))
-    if err != nil {
-        return err
-    }
-
-    fmt.Printf("\n")
-    //fmt.Printf("\r%s", strings.Repeat(" ", 40))
-    os.Rename(path + ".part", path)
-    //fmt.Printf("\r[%s] complete\n", path)
-    return nil
+	// make sure dir exists
+	os.MkdirAll(filepath.Dir(path), 0755)
+
+	// create .part file
+	output, err := os.Create(path + ".part")
+	if err != nil {
+		return err
+	}
+	defer output.Close()
+
+	// get data
+	response, err := http.Get(url)
+	if err != nil {
+		return err
+	}
+	defer response.Body.Close()
+
+	// create progress reporter
+	counter := NewWriteCounter(response.ContentLength)
+	_, err = io.Copy(output, io.TeeReader(response.Body, counter))
+	if err != nil {
+		return err
+	}
+
+	fmt.Printf("\n")
+	//fmt.Printf("\r%s", strings.Repeat(" ", 40))
+	os.Rename(path+".part", path)
+	//fmt.Printf("\r[%s] complete\n", path)
+	return nil
 }
diff --git a/tools/updater/main.go b/tools/updater/main.go
index f4feb62..1b2cc4c 100644
--- a/tools/updater/main.go
+++ b/tools/updater/main.go
@@ -1,63 +1,64 @@
 package main
 
 import (
-    "flag"
-    "fmt"
-    "os"
-    "net/http"
-    "bufio"
-    "strings"
+	"bufio"
+	"flag"
+	"fmt"
+	"net/http"
+	"os"
+	"strings"
 )
 
 func main() {
-    helpFlag := flag.Bool("help", false, "Show help information")
-    verboseFlag := flag.Bool("verbose", false, "Print more information")
-    repoFlag := flag.String("repo", "https://neueland.iserlohn-fortress.net/smolbote/downloads", "Repository path")
-    //dryRunFlag := flag.Bool("dry-run", false, "Dry run")
-
-    flag.Parse()
-
-    // help flag --> show usage and exit
-    if *helpFlag {
-        fmt.Println("Usage:")
-        flag.PrintDefaults()
-        os.Exit(0)
-    }
-
-    manifestPath := *repoFlag + "/windows-sha512.txt"
-    repoPath := *repoFlag + "/windows/"
-
-    if *verboseFlag {
-        fmt.Println("repoFlag =", *repoFlag)
-        fmt.Println("manifest =", manifestPath)
-        fmt.Println("repoPath =", repoPath)
-    }
-
-    response, err := http.Get(manifestPath)
-    if err != nil {
-        panic(err)
-    }
-    defer response.Body.Close()
-
-    scanner := bufio.NewScanner(response.Body)
-    for scanner.Scan() {
-        s := strings.Split(scanner.Text(), "  ")
-
-        filepath := s[1]
-        checksum := s[0]
-
-        state, err := checkFile(filepath, checksum)
-        if err != nil {
-            panic(err)
-        }
-
-        if(state) {
-            fmt.Printf("[%s] passed\n", filepath)
-        } else {
-            fmt.Printf("[%s] missing or mismatching\n", filepath)
-            downloadFile(filepath, repoPath + filepath)
-        }
-    }
+	helpFlag := flag.Bool("help", false, "Show help information")
+	verboseFlag := flag.Bool("verbose", false, "Print more information")
+	repoFlag := flag.String("repo", "https://neueland.iserlohn-fortress.net/smolbote/downloads", "Repository path")
+	dryRunFlag := flag.Bool("dry-run", false, "Dry run: only check files, do not download")
 
+	flag.Parse()
+
+	// help flag --> show usage and exit
+	if *helpFlag {
+		fmt.Println("Usage:")
+		flag.PrintDefaults()
+		os.Exit(0)
+	}
+
+	manifestPath := *repoFlag + "/windows-sha512.txt"
+	repoPath := *repoFlag + "/windows/"
+
+	if *verboseFlag {
+		fmt.Println("repoFlag =", *repoFlag)
+		fmt.Println("manifest =", manifestPath)
+		fmt.Println("repoPath =", repoPath)
+	}
+
+	response, err := http.Get(manifestPath)
+	if err != nil {
+		panic(err)
+	}
+	defer response.Body.Close()
+
+	scanner := bufio.NewScanner(response.Body)
+	for scanner.Scan() {
+		s := strings.Split(scanner.Text(), "  ")
+
+		filepath := s[1]
+		checksum := s[0]
+
+		state, err := checkFile(filepath, checksum)
+		if err != nil {
+			panic(err)
+		}
+
+		if state {
+			fmt.Printf("[%s] passed\n", filepath)
+		} else {
+			fmt.Printf("[%s] missing or mismatching\n", filepath)
+			if !*dryRunFlag {
+				downloadFile(filepath, repoPath+filepath)
+			}
+		}
+	}
 
 }
diff --git a/tools/updater/manifest.go b/tools/updater/manifest.go
index 942a5e7..0d8bfae 100644
--- a/tools/updater/manifest.go
+++ b/tools/updater/manifest.go
@@ -1,41 +1,41 @@
 package main
 
 import (
-    "crypto/sha512"
-    "os"
-    "io"
-    "fmt"
+	"crypto/sha512"
+	"fmt"
+	"io"
+	"os"
 )
 
 func checkFile(filepath string, checksum string) (bool, error) {
-    if _, err := os.Stat(filepath); os.IsNotExist(err) {
-        return false, nil
-    }
+	if _, err := os.Stat(filepath); os.IsNotExist(err) {
+		return false, nil
+	}
 
-    // file exists, check checksum
-    lsum, err := hash(filepath)
-    if err != nil {
-        return false, err
-    }
+	// file exists, check checksum
+	lsum, err := hash(filepath)
+	if err != nil {
+		return false, err
+	}
 
-    if checksum != fmt.Sprintf("%x", lsum) {
-        return false, nil
-    }
+	if checksum != fmt.Sprintf("%x", lsum) {
+		return false, nil
+	}
 
-    return true, nil
+	return true, nil
 }
 
 func hash(filepath string) ([]byte, error) {
-    file, err := os.Open(filepath)
-    if err != nil {
-        return nil, err
-    }
-    defer file.Close()
-
-    hasher := sha512.New()
-    if _, err := io.Copy(hasher, file); err != nil {
-        return nil, err
-    }
-
-    return hasher.Sum(nil), nil
+	file, err := os.Open(filepath)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	hasher := sha512.New()
+	if _, err := io.Copy(hasher, file); err != nil {
+		return nil, err
+	}
+
+	return hasher.Sum(nil), nil
 }