Patcher/pref.go

96 lines
2.7 KiB
Go

package main
import (
"bufio"
"fmt"
"os"
"strings"
)
// applyPrefModifications handles `t:pref` type patches
func applyPrefModifications(targetFilePath string, modifications []string) error {
// Open the target file
targetFile, err := os.Open(targetFilePath)
if err != nil {
return fmt.Errorf("failed to open target file: %v", err)
}
defer targetFile.Close()
// Create a temporary file
tempFilePath := targetFilePath + ".tmp"
tempFile, err := os.Create(tempFilePath)
if err != nil {
return fmt.Errorf("failed to create temp file: %v", err)
}
defer tempFile.Close()
// Parse modifications into a map for easy lookup
modMap := make(map[string]string)
for _, mod := range modifications {
if strings.HasPrefix(mod, "+pref") {
// Strip the `+` and extract the key within parentheses
start := strings.Index(mod, "(")
end := strings.LastIndex(mod, ")")
if start > 0 && end > start {
key := strings.TrimSpace(mod[start+1 : end]) // Extract the preference key
modMap[key] = strings.TrimPrefix(mod, "+") // Full modification line
}
}
}
scanner := bufio.NewScanner(targetFile)
modifiedLines := map[string]bool{} // Tracks applied modifications
// Process each line of the target file
for scanner.Scan() {
line := scanner.Text()
lineModified := false
// Check if the line matches any modification key
for key, replacement := range modMap {
if strings.Contains(line, key) && !modifiedLines[key] {
// Write the replacement line
fmt.Printf("Replacing line: %s\n", line)
if _, err := tempFile.WriteString(replacement + "\n"); err != nil {
return fmt.Errorf("failed to write to temp file: %v", err)
}
modifiedLines[key] = true
lineModified = true
break
}
}
// Write the original line if no modification matches
if !lineModified {
if _, err := tempFile.WriteString(line + "\n"); err != nil {
return fmt.Errorf("failed to write to temp file: %v", err)
}
}
}
if err := scanner.Err(); err != nil {
return fmt.Errorf("failed to read target file: %v", err)
}
// Append remaining modifications that were not in the file
for key, replacement := range modMap {
if !modifiedLines[key] {
fmt.Printf("Adding new preference: %s\n", replacement)
if _, err := tempFile.WriteString(replacement + "\n"); err != nil {
return fmt.Errorf("failed to append new preference to temp file: %v", err)
}
}
}
// Close the files to ensure proper cleanup
tempFile.Close()
targetFile.Close()
// Replace the original file with the modified temp file
if err := os.Rename(tempFilePath, targetFilePath); err != nil {
return fmt.Errorf("failed to replace target file: %v", err)
}
fmt.Println("Preferences successfully modified.")
return nil
}