autogenpb/protoReformat.go

// Copyright 2017-2025 WIT.COM Inc. All rights reserved.
// Use of this source code is governed by the GPL 3.0

package main

import (
	"fmt"
	"iter"
	"os"
	"regexp"
	"strings"
	sync "sync"

	"go.wit.com/log"
)

// like 'goimport', but for .proto files

var allTheLines *LinesScanner
var allTheNewLines []string
var lastMessage *FormatMsg

/*
type EnumMessage struct {
	msgPB *FormatMsg
	all   []Message
}

type StdMessage struct {
	msgPB *FormatMsg
	all   []Message
}

type Message interface {
	name() string
	addMsg(Message)
}
*/

// protoReformatComments reads a .proto file, processes its comments using
// commentPreprocessor and commentPreprocessorFull, and writes the modified
// content back to the file. This function serves as a dedicated comment
// processing tool.
func protoReformatComments(filename string) error {
	// read in the .proto file
	data, err := os.ReadFile(filename)
	if err != nil {
		log.Info("file read failed", filename, err)
		return err
	}

	var newfile string

	log.Info("filename", filename)
	alltest := makeLineIter(data)
	// gets the max vartype and varname
	for line := range alltest {
		newfile += fmt.Sprintln(commentPreprocessor(line))
	}
	newfile = commentPreprocessorFull(newfile)
	saveFile(filename, newfile)
	return nil
}

// protoReformat reads a .proto file, parses it into a structured format,
// aligns its contents for readability, and writes the formatted output back to
// the original file. It acts as the main entry point for the formatting process.
func protoReformat(filename string) error {
	// read in the .proto file
	data, err := os.ReadFile(filename)
	if err != nil {
		log.Info("file read failed", filename, err)
		return err
	}

	var newfile string

	basemsg := doParse(strings.Split(string(data), "\n"))

	for _, newline := range basemsg.format() {
		newfile += fmt.Sprintln(newline)
	}

	return saveFile(filename, newfile)
}

// doParse is the core parsing engine for the protoReformat tool. It processes
// the raw lines of a .proto file and constructs a hierarchical tree of
// FormatMsg structs.
//
// This tree mirrors the .proto file's logical structure, representing `message`,
// `enum`, and `oneof` blocks as distinct nodes. The function recursively
// handles nested definitions and carefully preserves associated comments and
// surrounding whitespace, which are essential for the final formatting.
//
// The returned *FormatMsg is the root of this tree, containing the complete,
// structured representation of the file, which is then used by the format
// functions to generate a clean, aligned output.
func doParse(lines []string) *FormatMsg {
	var comments string

	var basemsg *FormatMsg
	basemsg = new(FormatMsg)
	lastMessage = basemsg

	// TODO: read in start of the file
	allTheLines = newLinesScanner(lines)
	for allTheLines.Scan() {
		line := allTheLines.NextRaw()
		if strings.HasPrefix(line, "oneof ") {
			break
		}
		if strings.HasPrefix(line, "enum ") {
			break
		}
		if strings.HasPrefix(line, "message ") {
			break
		}
		basemsg.Notes = append(basemsg.Notes, line)
	}
	// rewind a line
	allTheLines.UnScan()

	// write out the messages
	for allTheLines.Scan() {
		line := allTheLines.NextRaw()

		if strings.HasPrefix(line, "oneof ") {
			if strings.Contains(line, "}") {
				newmsg := basemsg.newMessage(line, comments, FormatMsg_ONEOF)
				newmsg.IsEmpty = true
				newmsg.Footer = "} // blah"
				comments = ""
				continue
			}
			newmsg := basemsg.newMessage(line, comments, FormatMsg_ONEOF)
			comments = ""
			newmsg.load()
			continue
		}

		if strings.HasPrefix(line, "enum ") {
			newmsg := basemsg.newMessage(line, comments, FormatMsg_ENUM)
			comments = ""
			if strings.Contains(line, "}") {
				newmsg.IsEmpty = true
				newmsg.Footer = "} // blah"
				continue
			}
			newmsg.load()
			continue
		}

		if strings.HasPrefix(line, "message ") {
			log.Info("got to message", line)
			newmsg := basemsg.newMessage(line, comments, FormatMsg_MESSAGE)
			comments = ""
			if strings.Contains(line, "}") {
				newmsg.IsEmpty = true
				newmsg.Footer = "} // blah"
				continue
			}
			newmsg.load()
			continue
		}

		if comments == "" {
			if strings.TrimSpace(line) == "" {
				lastMessage.PadAfter = true
			}
		}
		comments += fmt.Sprintln(line)
	}

	return basemsg
}

// saveFile writes the provided data to a specified file, creating it if it
// doesn't exist or truncating it if it does. It ensures the data is trimmed of
// surrounding whitespace before writing.
func saveFile(filename string, data string) error {
	pf, err := os.OpenFile(filename, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0644)
	if err != nil {
		log.Info("file open error. permissions?", filename, err)
		return err
	}
	data = strings.TrimSpace(data)
	fmt.Fprintln(pf, data)
	pf.Close()

	// for i, s := range slices.Backward(pf.ToSort) {
	return nil
}

// newDepth creates a new FormatMsg, representing a nested message structure.
// It inherits formatting parameters from its parent and increments the nesting
// depth, which is used to calculate indentation.
func newDepth(fmtmsg *FormatMsg, header string) *FormatMsg {
	newmsg := new(FormatMsg)
	lastMessage = newmsg
	newmsg.MaxVarname = fmtmsg.MaxVarname
	newmsg.MaxVartype = fmtmsg.MaxVartype
	newmsg.Header = strings.TrimSpace(header)
	newmsg.Depth = fmtmsg.Depth + 1

	return newmsg
}

// newMessage creates a new FormatMsg of a specified type (e.g., message, enum)
// and appends it to the parent's list of messages. It associates the new
// message with its preceding comments.
func (msgPB *FormatMsg) newMessage(header string, comments string, msgType FormatMsg_Type) *FormatMsg {
	newmsg := newDepth(msgPB, header)
	newmsg.Type = msgType
	msgPB.Msgs = append(msgPB.Msgs, newmsg)

	comments = strings.TrimSpace(comments)
	newmsg.Notes = strings.Split(comments, "\n")

	return newmsg
}

// load recursively parses the content within a message, enum, or oneof block.
// It consumes lines from the global line scanner until it reaches the closing
// brace '}' of the current block, creating nested messages as needed.
func (msg *FormatMsg) load() {
	// fmtmsg := msg.msgPB
	for allTheLines.Scan() {
		line := allTheLines.Next()
		if strings.HasPrefix(line, "oneof ") {
			newmsg := msg.newMessage(line, "", FormatMsg_ONEOF)
			if strings.Contains(line, "}") {
				newmsg.IsEmpty = true
				return
			}
			newmsg.load()
			continue
		}
		if strings.HasPrefix(line, "enum ") {
			newmsg := msg.newMessage(line, "", FormatMsg_ENUM)
			if strings.Contains(line, "}") {
				newmsg.IsEmpty = true
				return
			}
			newmsg.load()
			continue
		}
		if strings.HasPrefix(line, "message ") {
			// message inception. search for the architect. don't forget your totem
			newmsg := msg.newMessage(line, "", FormatMsg_MESSAGE)
			if strings.Contains(line, "}") {
				newmsg.IsEmpty = true
				return
			}
			newmsg.load()
			continue
		}
		if strings.HasPrefix(line, "}") {
			msg.Footer = line
			return
		}
		msg.Lines = append(msg.Lines, line)
	}

	return
}

// tokenMsgVar parses a line containing a field definition within a .proto message.
// It extracts and returns the variable type, name, ID, and any trailing comments
// or options. For example, from "string name = 1; // User's name", it returns
// "string", "name", "1", and "// User's name".
func tokenMsgVar(line string) (string, string, string, string) {
	parts := strings.Split(line, ";")
	front := parts[0]
	end := strings.Join(parts[1:], ";")

	var id string
	var varname string
	var vartype string

	parts = strings.Fields(front)
	parts, id = slicesPop(parts)
	parts, _ = slicesPop(parts) // this is the "=" sign
	parts, varname = slicesPop(parts)
	vartype = strings.Join(parts, " ")

	return vartype, varname, id, end
}

// slicesPop removes and returns the last element from a slice of strings,
// along with the modified slice. It is a utility function for tokenizing lines.
func slicesPop(parts []string) ([]string, string) {
	if len(parts) == 0 {
		return nil, ""
	}
	if len(parts) == 1 {
		return nil, parts[0]
	}
	x := len(parts)
	end := parts[x-1]
	return parts[0 : x-1], end
}

// makeLineIter creates a Go 1.24+ style iterator (iter.Seq) from a byte slice
// of file content. This allows for convenient line-by-line iteration using
// `for ... range`.
func makeLineIter(data []byte) iter.Seq[string] {
	items := strings.Split(string(data), "\n")
	// log.Println("Made All() Iter.Seq[] with length", len(items))
	return func(yield func(string) bool) {
		for _, v := range items {
			if !yield(v) {
				return
			}
		}
	}
}

// setMaxSizes calculates the maximum length of field types and names within a
// message. These values are used later to determine the padding required for
// consistent alignment of fields.
func setMaxSizes(curmsg *FormatMsg) {
	for _, line := range curmsg.Lines {
		parts := strings.Split(line, ";")
		if len(parts) < 2 {
			// line is blank or just a comment
			continue
		}

		vartype, varname, _, _ := tokenMsgVar(line)
		if len(vartype) > int(curmsg.MaxVartype) {
			curmsg.MaxVartype = int64(len(vartype))
		}
		if len(varname) > int(curmsg.MaxVarname) {
			curmsg.MaxVarname = int64(len(varname))
		}
	}
}

// padBase generates the indentation string for message headers and footers
// based on their nesting depth.
func (msg *FormatMsg) padBase() string {
	var pad string
	for i := 1; i < int(msg.Depth); i += 1 {
		pad += fmt.Sprintf("%8s", " ")
	}
	return pad
}

// pad generates the indentation string for lines inside a message block,
// such as field definitions, based on the message's nesting depth.
func (msg *FormatMsg) pad() string {
	var pad string
	for i := 0; i < int(msg.Depth); i += 1 {
		pad += fmt.Sprintf("%8s", " ")
	}
	return pad
}

// padding generates an indentation string with a custom offset, allowing for
// flexible alignment calculations.
func (msg *FormatMsg) padding(offset int) string {
	var pad string
	for i := offset; i < int(msg.Depth); i += 1 {
		pad += fmt.Sprintf("%8s", " ")
	}
	return pad
}

// formatEnum formats an enum block, including its header, values, and footer,
// ensuring proper indentation.
func formatEnum(curmsg *FormatMsg) []string {
	var newmsg []string
	newmsg = append(newmsg, curmsg.formatLineBase(curmsg.Header, "enum header"))

	for _, line := range curmsg.Lines {
		newmsg = append(newmsg, curmsg.formatLine(line, "enum"))
	}

	// newmsg = append(newmsg, curmsg.formatLineBase(curmsg.Footer, "enum footer"))
	newmsg = append(newmsg, curmsg.formatFooter(curmsg.Footer, "enum footer"))
	if curmsg.PadAfter {
		newmsg = append(newmsg, curmsg.formatPadAfter())
	}

	return newmsg
}

// formatOneof formats a oneof block, aligning its fields and comments
// according to the calculated padding.
func formatOneof(curmsg *FormatMsg) []string {
	// curmsg.formatStandardSizes()

	var newmsg []string
	newmsg = append(newmsg, curmsg.formatLineBase(curmsg.Header, "oneof header"))

	for _, line := range curmsg.Lines {
		// func (msg *FormatMsg) formatMsgLine(line string, dbg string) string {
		newmsg = append(newmsg, curmsg.formatMsgLine(line, "oneof"))
	}

	// newmsg = append(newmsg, curmsg.formatLineBase(curmsg.Footer, "oneof footer"))
	newmsg = append(newmsg, curmsg.formatFooter(curmsg.Footer, "oneof footer"))
	if curmsg.PadAfter {
		newmsg = append(newmsg, curmsg.formatPadAfter())
	}

	return newmsg
}

// formatStandardSizes traverses the message tree and standardizes the padding
// for field types and names across all sibling messages. This ensures that
// fields in adjacent messages are vertically aligned, improving readability.
func (parent *FormatMsg) formatStandardSizes() {
	var bigType int64
	var bigName int64

	// find the biggest var names and var types
	for _, child := range parent.Msgs {
		switch child.Type {
		case FormatMsg_ENUM:
		case FormatMsg_ONEOF:
			// find the max length of varname and vartype
			setMaxSizes(child)
			if bigType < child.MaxVartype {
				bigType = child.MaxVartype
			}
			if bigName < child.MaxVarname {
				bigName = child.MaxVarname
			}
		case FormatMsg_MESSAGE:
			// find the max length of varname and vartype
			setMaxSizes(child)
			if bigType < child.MaxVartype {
				bigType = child.MaxVartype
			}
			if bigName < child.MaxVarname {
				bigName = child.MaxVarname
			}
		default:
		}
	}

	// set this size in each message
	for _, child := range parent.Msgs {
		switch child.Type {
		case FormatMsg_ENUM:
		case FormatMsg_ONEOF:
			child.MaxVartype = bigType
			child.MaxVarname = bigName
		case FormatMsg_MESSAGE:
			child.MaxVartype = bigType
			child.MaxVarname = bigName
		default:
		}
	}
}

// format is the main formatting dispatcher. It calls the appropriate formatting
// function (formatEnum, formatOneof, or formatMessage) based on the message type.
func (parent *FormatMsg) format() []string {
	parent.formatStandardSizes()

	switch parent.Type {
	case FormatMsg_ENUM:
		return formatEnum(parent)
	case FormatMsg_ONEOF:
		return formatOneof(parent)
	case FormatMsg_MESSAGE:
		return formatMessage(parent)
	default:
		return formatMessage(parent)
	}
}

// formatFooter formats the closing brace '}' of a message block, applying the
// correct base indentation.
func (msg *FormatMsg) formatFooter(line string, dbg string) string {
	if line == "" {
		if argv.Debug {
			return "// footer was empty"
		}
		return ""
	}
	return msg.formatLineBase(line, "footer")
}

// formatPadAfter adds a blank line after a message block if the original
// file contained one, preserving vertical spacing.
func (msg *FormatMsg) formatPadAfter() string {
	if argv.Debug {
		return msg.formatLineBase("", "pad after")
	}
	return ""
}

// formatHeader formats the opening line of a message block (e.g., "message Foo {"),
// aligning any trailing comments.
func (msg *FormatMsg) formatHeader(line string, dbg string) string {
	if line == "" {
		if msg.Depth != 0 {
			return "// ERROR: header was blank"
		}
	}

	parts := strings.Fields(line)
	if len(parts) <= 3 {
		return msg.formatLineBase(msg.Header, "header")
	}

	// hack to actually indent comments on the message line itself. you're welcome
	start := parts[0] + " " + parts[1] + " " + parts[2]
	end := strings.Join(parts[3:], " ")
	offset := int(msg.MaxVarname) + int(msg.MaxVartype) + 16 - len(start)
	pad := fmt.Sprintf("%d", offset)
	if argv.Debug {
		hmm := "%s%s     %" + pad + "s %s // depth=%d"
		return fmt.Sprintf(hmm, msg.padBase(), start, " ", end, msg.Depth)
	}
	hmm := "%s%s     %" + pad + "s %s"
	return fmt.Sprintf(hmm, msg.padBase(), start, " ", end)
}

// formatLineBase formats a line using the base indentation level, suitable for
// headers, footers, and comments outside of message bodies.
func (msg *FormatMsg) formatLineBase(line string, dbg string) string {
	line = strings.TrimSpace(line)
	if argv.Debug {
		return fmt.Sprintf("/*a*/%s/*b*/%s // %s depth=%d", msg.padBase(), line, dbg, msg.Depth)
	}
	return fmt.Sprintf("%s%s", msg.padBase(), line)
}

// formatLine formats a line using the standard block indentation, suitable for
// field definitions and other content inside a message body.
func (msg *FormatMsg) formatLine(line string, dbg string) string {
	line = strings.TrimSpace(line)
	if argv.Debug {
		return fmt.Sprintf("/*a*/%s/*b*/%s // %s depth=%d", msg.pad(), line, dbg, msg.Depth)
	}
	return fmt.Sprintf("%s%s", msg.pad(), line)
}

// formatComment formats a comment line, aligning it with the surrounding code
// based on the calculated maximum field widths.
func (msg *FormatMsg) formatComment(line string, dbg string) string {
	line = strings.TrimSpace(line)
	pad := fmt.Sprintf("%d", msg.MaxVartype+msg.MaxVarname+13) // 21 is correct?
	hmm := "%" + pad + "s %s"
	comment := fmt.Sprintf(hmm, " ", line) // todo: compute 50
	if argv.Debug {
		return fmt.Sprintf("/*a*/%s/*b*/%s // %s depth=%d", msg.pad(), comment, dbg, msg.Depth)
	}
	return fmt.Sprintf("%s%s", msg.pad(), comment)
}

// formatVarLine formats a field definition line, padding the type and name to
// ensure vertical alignment with other fields in the same scope.
func (msg *FormatMsg) formatVarLine(line string, dbg string) string {
	line = strings.TrimSpace(line)
	mt := fmt.Sprintf("%d", msg.MaxVartype)
	mv := fmt.Sprintf("%d", msg.MaxVarname)

	hmm := "%-" + mt + "s   %-" + mv + "s     = %-3s %s"

	vartype, varname, id, end := tokenMsgVar(line)
	end = strings.TrimSpace(end)
	id = id + ";"

	newline := fmt.Sprintf(hmm, vartype, varname, id, end)
	newline = strings.TrimRight(newline, " ")

	if argv.Debug {
		return fmt.Sprintf("/*a*/%s/*b*/%s // %s depth=%d (%d,%d)", msg.pad(), newline, dbg, msg.Depth, msg.MaxVartype, msg.MaxVarname)
	}
	return fmt.Sprintf("%s%s", msg.pad(), newline)
}

// formatMsgLine is a dispatcher for formatting a single line within a message.
// It determines whether the line is a comment or a field definition and calls
// the appropriate formatting function.
func (msg *FormatMsg) formatMsgLine(line string, dbg string) string {
	line = strings.TrimSpace(line)
	if line == "" {
		if argv.Debug {
			return "// empty line " + msg.Header + " empty line end"
		} else {
			return line
		}
	}
	if strings.HasPrefix(line, "//") {
		return msg.formatComment(line, "comment")
	}
	return msg.formatVarLine(line, "var "+dbg)
}

// trimLines removes leading/trailing whitespace and blank lines from a slice
// of strings by joining and splitting them.
func trimLines(lines []string) []string {
	return strings.Split(strings.TrimSpace(strings.Join(lines, "\n")), "\n")
}

// formatMessage is the main function for formatting a `message` block. It
// orchestrates the formatting of comments, nested messages, and field
// definitions to produce a clean, aligned output.
func formatMessage(curmsg *FormatMsg) []string {
	var newmsg []string

	if curmsg.IsEmpty {
		newmsg = append(newmsg, curmsg.formatLineBase("// isEmpty", "IsEmpty"))
		return newmsg
	}

	// add the notes & comments before the header
	notes := trimLines(curmsg.Notes)
	if len(notes) == 0 {
		// do nothing {
	} else if len(notes) == 1 {
		if notes[0] == "" {
			// todo: track space in original file
		} else {
			newmsg = append(newmsg, curmsg.formatLineBase(notes[0], "notes1"))
		}
	} else {
		for _, line := range notes {
			newmsg = append(newmsg, curmsg.formatLineBase(line, "notes2"))
		}
	}

	newmsg = append(newmsg, curmsg.formatHeader(curmsg.Header, "header"))

	for _, msg := range curmsg.Msgs {
		switch msg.Type {
		case FormatMsg_ENUM:
			for _, line := range formatEnum(msg) {
				newmsg = append(newmsg, line)
			}
		case FormatMsg_ONEOF:
			for _, line := range formatOneof(msg) {
				newmsg = append(newmsg, line)
			}
		case FormatMsg_MESSAGE:
			for _, line := range msg.format() {
				// line = fmt.Sprintf("%s%s", curmsg.pad(), line)
				newmsg = append(newmsg, line)
			}
		default:
		}
	}

	// trim curmsg.Lines
	// if curmsg.Lines is empty, don't do anything
	dump := strings.Join(curmsg.Lines, "\n")
	dump = strings.TrimSpace(dump)

	if dump == "" {
		// do nothing
	} else {
		// print the lines
		curmsg.Lines = strings.Split(dump, "\n")
		// newmsg = append(newmsg, "// dump "+dump+"dump end\n")

		for _, line := range curmsg.Lines {
			line = strings.TrimSpace(line)
			if line == "" {
				if argv.Debug {
					newmsg = append(newmsg, "// empty line "+curmsg.Header+" empty line end")
				} else {
					newmsg = append(newmsg, line)
				}
				continue
			}
			if strings.HasPrefix(line, "//") {
				/*
					pad := fmt.Sprintf("%d", curmsg.MaxVartype+curmsg.MaxVarname+21)
					hmm := "%" + pad + "s %s"
					line = fmt.Sprintf(hmm, " ", line) // todo: compute 50
					newmsg = append(newmsg, line)
				*/
				newmsg = append(newmsg, curmsg.formatComment(line, "comment"))
				continue
			}
			newmsg = append(newmsg, curmsg.formatVarLine(line, "var"))
		}
	}

	newmsg = append(newmsg, curmsg.formatFooter(curmsg.Footer, "footer"))
	if curmsg.PadAfter {
		newmsg = append(newmsg, curmsg.formatPadAfter())
	}

	return newmsg
}

// DEFINE THE Lines ITERATOR.

// newLinesScanner initializes a new LinesScanner iterator with a slice of strings.
func newLinesScanner(things []string) *LinesScanner {
	return &LinesScanner{things: things}
}

// LinesScanner provides an iterator over a slice of strings, allowing for
// sequential access and the ability to un-scan (step back).
type LinesScanner struct {
	sync.Mutex

	things []string
	index  int
}

// Scan advances the iterator to the next line. It returns false if there are
// no more lines.
func (it *LinesScanner) Scan() bool {
	if it.index >= len(it.things) {
		return false
	}
	it.Lock()
	it.index++
	it.Unlock()
	return true
}

// UnScan moves the iterator back one line. It returns false if the iterator
// is already at the beginning.
func (it *LinesScanner) UnScan() bool {
	if it.index < 1 {
		it.index = 0
		return false
	}
	it.Lock()
	it.index--
	it.Unlock()
	return true
}

// NextRaw returns the current line from the scanner without any modification.
func (it *LinesScanner) NextRaw() string {
	if it.index-1 == len(it.things) {
		fmt.Println("Next() error in LinesScanner", it.index)
	}
	return it.things[it.index-1]
}

// Next returns the current line from the scanner with leading and trailing
// whitespace removed.
func (it *LinesScanner) Next() string {
	if it.index-1 == len(it.things) {
		fmt.Println("Next() error in LinesScanner", it.index)
	}
	// out := commentPreprocessor(it.things[it.index-1])
	out := it.things[it.index-1]
	return strings.TrimSpace(out)
	// return out
}

// END DEFINE THE ITERATOR

// commentPreprocessor converts single-line C-style block comments (/* ... */)
// into Go-style line comments (// ...) appended to the end of the line.
// For example, "/* test */ reserved 4;" becomes "reserved 4; // test".
func commentPreprocessor(line string) string {
	// Match all /* comment */ blocks
	re := regexp.MustCompile(`/\*([^*]+)\*/`)
	matches := re.FindAllStringSubmatch(line, -1)

	// Extract just the comment texts
	var comments []string
	for _, match := range matches {
		comments = append(comments, strings.TrimSpace(match[1]))
		// comments = append(comments, match[1])
	}

	// Remove the block comments from the original line
	line = re.ReplaceAllString(line, "")
	// line = strings.TrimSpace(line)
	line = strings.TrimSuffix(line, " ")

	// Append comments at the end with //
	for _, comment := range comments {
		line += " // " + comment
	}

	return line
}

// commentPreprocessorFull transforms multi-line C-style block comments
// (/* ... */) into a series of single-line Go-style comments (// ...).
func commentPreprocessorFull(full string) string {
	// Match all /* comment */ blocks
	// re := regexp.MustCompile(`/\*([^*]+)\*/`)
	re := regexp.MustCompile(`(?s)/\*(.*?)\*/`)

	return re.ReplaceAllStringFunc(full, func(s string) string {
		log.Info("FOUND:\n", s)
		lines := strings.Split(s, "\n")
		var cleaned []string

		for _, line := range lines {
			trimmed := strings.TrimSpace(line)

			switch {
			case strings.HasPrefix(trimmed, "/*"):
				trimmed = trimCommentPrefix(trimmed)
			case strings.HasPrefix(trimmed, "*/"):
				trimmed = strings.TrimPrefix(trimmed, "*/")
			case strings.HasPrefix(trimmed, "*"):
				trimmed = strings.TrimPrefix(trimmed, "*")
			}
			trimmed = "// " + trimmed

			cleaned = append(cleaned, strings.TrimSpace(trimmed))
		}

		s = strings.Join(cleaned, "\n")
		log.Info("NOW:\n", s)
		return s
	})
}

// trimCommentPrefix is a helper function for commentPreprocessorFull that
// removes leading comment markers like '/*', '*', and '*/' from a line.
func trimCommentPrefix(line string) string {
	trimmed := strings.TrimSpace(line)

	if strings.HasPrefix(trimmed, "/") {
		i := 1
		for i < len(trimmed) && trimmed[i] == '*' {
			i++
		}
		if i > 1 {
			return strings.TrimSpace(trimmed[i:])
		}
	}

	if strings.HasPrefix(trimmed, "*") {
		return strings.TrimSpace(trimmed[1:])
	}

	if trimmed == "*/" {
		return ""
	}

	return trimmed
}