Initial commit

main.go

@@ -0,0 +1,147 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"os"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+const deliminer = ","
+const (
+	Black   = "\033[30m"
+	Red     = "\033[31m"
+	Green   = "\033[32m"
+	Yellow  = "\033[33m"
+	Blue    = "\033[34m"
+	Magenta = "\033[35m"
+	Cyan    = "\033[36m"
+	White   = "\033[37m"
+)
+const SourceColor = Magenta
+const TargetColor = Yellow
+const ErrorColor = Red
+const DefaultColor = White
+
+type LinkInstruction struct {
+	Source string
+	Target string
+	Force  bool
+}
+
+func InstructionToString(instruction LinkInstruction) string {
+	return fmt.Sprintf("%s%s%s%s%s%s%s%s%s", SourceColor, instruction.Source, DefaultColor, deliminer, TargetColor, instruction.Target, DefaultColor, deliminer, strconv.FormatBool(instruction.Force))
+}
+
+func main() {
+	// Format:
+	// source|target|force?
+	log.SetFlags(log.Lmicroseconds)
+	var inputs []string
+	// os.Chdir("C:/Users/Administrator/Seafile/Last-Epoch-Backup")
+
+	if len(os.Args) > 1 {
+		inputs = append(inputs, os.Args[1:]...)
+	} else {
+		info, err := os.Stdin.Stat()
+		if err != nil {
+			log.Fatalf("Failed to stat stdin: %s%+v%s", ErrorColor, err, DefaultColor)
+		}
+		if info.Mode()&os.ModeNamedPipe != 0 {
+			scanner := bufio.NewScanner(os.Stdin)
+			for scanner.Scan() {
+				inputs = append(inputs, scanner.Text())
+			}
+			if err := scanner.Err(); err != nil {
+				log.Fatalf("Error reading from stdin: %s%+v%s", ErrorColor, err, DefaultColor)
+			}
+		}
+	}
+
+	if len(inputs) == 0 {
+		log.Printf("No input provided")
+		log.Printf("Supply input as either arguments (source,target,force?)")
+		log.Printf("or via stdin (cat <file> | %s)", os.Args[0])
+		os.Exit(1)
+	}
+
+	for _, line := range inputs {
+		instruction, err := parseLine(line)
+		if err != nil {
+			log.Printf("Error parsing line: %s'%s'%s, error: %s%+v%s", SourceColor, line, DefaultColor, ErrorColor, err, DefaultColor)
+			continue
+		}
+		log.Printf("Processing: %s", InstructionToString(instruction))
+		err = processInstruction(instruction)
+		if err != nil {
+			log.Printf("Failed parsing instruction %s%s%s due to %s%+v%s", SourceColor, InstructionToString(instruction), DefaultColor, ErrorColor, err, DefaultColor)
+			continue
+		}
+	}
+}
+func parseLine(line string) (LinkInstruction, error) {
+	parts := strings.Split(line, deliminer)
+	instruction := LinkInstruction{}
+
+	if len(parts) < 2 {
+		return instruction, fmt.Errorf("invalid format - not enough parameters (must have at least source and target)")
+	}
+
+	instruction.Source = parts[0]
+	instruction.Target = parts[1]
+	instruction.Force = false
+	if len(parts) > 2 {
+		res, _ := regexp.MatchString("^(?i)T|TRUE$", parts[2])
+		instruction.Force = res
+	}
+
+	instruction.Source, _ = ConvertHome(instruction.Source)
+	instruction.Target, _ = ConvertHome(instruction.Target)
+
+	instruction.Source = NormalizePath(instruction.Source)
+	instruction.Target = NormalizePath(instruction.Target)
+
+	return instruction, nil
+}
+
+func processInstruction(instruction LinkInstruction) error {
+	if !FileExists(instruction.Source) {
+		return fmt.Errorf("instruction source %s%s%s does not exist", SourceColor, instruction.Source, DefaultColor)
+	}
+
+	if AreSame(instruction.Source, instruction.Target) {
+		log.Printf("Source %s%s%s and target %s%s%s are the same, nothing to do...", SourceColor, instruction.Source, DefaultColor, TargetColor, instruction.Target, DefaultColor)
+		return nil
+	}
+
+	if FileExists(instruction.Target) {
+		if instruction.Force {
+			isSymlink, err := IsSymlink(instruction.Target)
+			if err != nil {
+				return fmt.Errorf("could not determine whether %s%s%s is a sym link or not, stopping; err: %s%+v%s", TargetColor, instruction.Target, DefaultColor, ErrorColor, err, DefaultColor)
+			}
+
+			if isSymlink {
+				log.Printf("Removing symlink at %s%s%s", TargetColor, instruction.Target, DefaultColor)
+				err = os.Remove(instruction.Target)
+				if err != nil {
+					return fmt.Errorf("failed deleting %s%s%s due to %s%+v%s", TargetColor, instruction.Target, DefaultColor, ErrorColor, err, DefaultColor)
+				}
+			} else {
+				return fmt.Errorf("refusing to delte actual (non symlink) file %s%s%s", TargetColor, instruction.Target, DefaultColor)
+			}
+		} else {
+			return fmt.Errorf("target %s%s%s exists - handle manually or set the 'forced' flag (3rd field)", TargetColor, instruction.Target, DefaultColor)
+		}
+	}
+
+	err := os.Symlink(instruction.Source, instruction.Target)
+	if err != nil {
+		return fmt.Errorf("failed creating symlink between %s%s%s and %s%s%s with error %s%+v%s", SourceColor, instruction.Source, DefaultColor, TargetColor, instruction.Target, DefaultColor, ErrorColor, err, DefaultColor)
+	}
+
+	return nil
+}