Implemented the tree structure generator

Author: 4r7if3x

cmd/root.go

@@ -37,7 +37,11 @@ var rootCmd = &cobra.Command{
 			return
 		}
 
-		internal.Help()
+		processed := internal.ProcessInput(args)
+
+		if !processed {
+			internal.Help()
+		}
 	},
 }
 

internal/filesystem.go

@@ -0,0 +1,41 @@
+package internal
+
+import (
+	"errors"
+	"fmt"
+	"os"
+)
+
+func createDirectory(path string) {
+	err := os.MkdirAll(path, 0755)
+
+	if err != nil {
+		if Verbose && os.IsExist(err) {
+			fmt.Println(err)
+		} else {
+			FatalError(err)
+		}
+	}
+}
+
+func createFile(path string) {
+	var modes int
+
+	if Force {
+		modes = os.O_CREATE | os.O_TRUNC
+	} else {
+		modes = os.O_CREATE | os.O_EXCL
+	}
+
+	file, err := os.OpenFile(path, modes, 0644)
+
+	if err != nil {
+		if Verbose && errors.Is(err, os.ErrExist) {
+			fmt.Println(err)
+		} else {
+			FatalError(err)
+		}
+	}
+
+	defer file.Close()
+}

internal/generate.go

@@ -0,0 +1,79 @@
+package internal
+
+import (
+	"path/filepath"
+	"strings"
+)
+
+const (
+	gap         = "    "
+	ascChild    = "├── "
+	ascSubChild = "│   "
+	ascEndChild = "└── "
+	txtChild    = "|-- "
+	txtSubChild = "|   "
+	txtEndChild = "+-- "
+)
+
+func generate(lines []string) {
+	level := 0
+	dir := lines[0]
+
+	createDirectory(dir)
+
+	for i, line := range lines[1:] {
+		currentLevel := nodeLevel(line)
+
+		if currentLevel > level {
+			parentDir := nodeName(lines[i]) // name of previous line
+			dir = dir + parentDir
+			level++
+		} else if currentLevel < level {
+			dir = strings.TrimRight(dir, "/")
+			dir = moveUpDirectories(dir, level-currentLevel)
+			dir = dir + "/"
+			level = currentLevel // could drop down multiple levels
+		}
+
+		nodePath := dir + nodeName(line)
+
+		if strings.HasSuffix(nodePath, "/") {
+			createDirectory(nodePath)
+		} else {
+			createFile(nodePath)
+		}
+	}
+}
+
+func nodeLevel(line string) int {
+	level := 0
+
+	for {
+		if strings.HasPrefix(line, ascSubChild) {
+			level++
+			line = line[len(ascSubChild):]
+		} else if strings.HasPrefix(line, txtSubChild) {
+			level++
+			line = line[len(txtSubChild):]
+		} else if strings.HasPrefix(line, gap) {
+			level++
+			line = line[len(gap):]
+		} else {
+			break
+		}
+	}
+
+	return level
+}
+
+func nodeName(line string) string {
+	return strings.TrimLeft(line, "└├ ─│|+-")
+}
+
+func moveUpDirectories(path string, n int) string {
+	for i := 0; i < n; i++ {
+		path = filepath.Dir(path)
+	}
+
+	return path
+}

internal/input.go

@@ -0,0 +1,76 @@
+package internal
+
+import (
+	"bufio"
+	"os"
+)
+
+func ProcessInput(args []string) bool {
+	processed := false
+
+	if len(args) > 0 {
+		for _, path := range args {
+			tree := readFromFile(path)
+
+			if len(tree) > 0 {
+				generate(tree)
+				processed = true
+			}
+		}
+	}
+
+	tree := readFromStdIn()
+
+	if len(tree) > 0 {
+		generate(tree)
+		processed = true
+	}
+
+	return processed
+}
+
+func readFromFile(path string) []string {
+	file, err := os.Open(path)
+
+	if err != nil {
+		FatalError(err)
+	}
+
+	defer file.Close()
+
+	scanner := bufio.NewScanner(file)
+
+	var lines []string
+
+	for scanner.Scan() {
+		lines = append(lines, scanner.Text())
+	}
+
+	if err := scanner.Err(); err != nil {
+		FatalError(err)
+	}
+
+	return lines
+}
+
+func readFromStdIn() []string {
+	stat, _ := os.Stdin.Stat()
+
+	if (stat.Mode() & os.ModeCharDevice) != 0 {
+		return []string{}
+	}
+
+	scanner := bufio.NewScanner(os.Stdin)
+
+	var lines []string
+
+	for scanner.Scan() {
+		lines = append(lines, scanner.Text())
+	}
+
+	if err := scanner.Err(); err != nil {
+		FatalError(err)
+	}
+
+	return lines
+}