#19 Transform-to-and-from-POT (#26)

* #19 Transform-to-and-from-POT

* #19 Transform-to-and-from-POT

* #19 Tidy

* #19 minor fixes

* #19 minor fixes

* #19 minor fixes

* #19 fixes

* #19 changed multiline msgdid and msgstr

* #19 modified ToPot function

* #19 fixes

* #19 modified multiline functionality

* #19 added error to lexer function

* #19 added quoted string support in lex function and made fixes

* #19 changed fully Lex function because of gocognit

* #19 changed PoTag -> poTag

* #19 changed identifiers to private

* #19 added comment multiline support

* #19 fixes

* #34 transform to and from XMB

* 17-transform-to-and-from-arb (#20)

* File-upload2 (#13)

* 21-download-file (#22)

* Instrument traces (OpenTelemetry) (#24)

* #27 Upgraded earthly to 0.7 (#28)

* #25 Added configuration from various sources (#29)

* 32-transform-to-and-from-xliff-2 (#33)

* 18-transform-to-and-from-angularlocalize (#31)

* Renamed table test fields for consistency (#38)

---------

Co-authored-by: Vladislavs Perkaņuks <[email protected]>

pkg/convert/pot.go

@@ -0,0 +1,156 @@
+package convert
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"strings"
+
+	"go.expect.digital/translate/pkg/model"
+	"go.expect.digital/translate/pkg/pot"
+)
+
+type poTag string
+
+const (
+	MsgId  poTag = "msgid"
+	MsgStr poTag = "msgstr"
+)
+
+func ToPot(m model.Messages) ([]byte, error) {
+	var b bytes.Buffer
+
+	if _, err := fmt.Fprintf(&b, "\"Language: %s\n", m.Language); err != nil {
+		return nil, fmt.Errorf("write language: %w", err)
+	}
+
+	for i, message := range m.Messages {
+		if i > 0 {
+			if _, err := fmt.Fprint(&b, "\n"); err != nil {
+				return nil, fmt.Errorf("write new line: %w", err)
+			}
+		}
+
+		descriptions := strings.Split(message.Description, "\n")
+
+		for _, description := range descriptions {
+			if description != "" {
+				if _, err := fmt.Fprintf(&b, "#. %s\n", description); err != nil {
+					return nil, fmt.Errorf("write description: %w", err)
+				}
+			}
+		}
+
+		if message.Fuzzy {
+			if _, err := fmt.Fprint(&b, "#, fuzzy\n"); err != nil {
+				return nil, fmt.Errorf("write fuzzy: %w", err)
+			}
+		}
+
+		err := writeToPoTag(&b, MsgId, message.ID)
+		if err != nil {
+			return nil, fmt.Errorf("format msgid: %w", err)
+		}
+
+		err = writeToPoTag(&b, MsgStr, message.Message)
+		if err != nil {
+			return nil, fmt.Errorf("format msgstr: %w", err)
+		}
+	}
+
+	return b.Bytes(), nil
+}
+
+func FromPot(b []byte) (model.Messages, error) {
+	tokens, err := pot.Lex(bytes.NewReader(b))
+	if err != nil {
+		return model.Messages{}, fmt.Errorf("dividing po file to tokens: %w", err)
+	}
+
+	po, err := pot.TokensToPo(tokens)
+	if err != nil {
+		return model.Messages{}, fmt.Errorf("convert tokens to pot.Po: %w", err)
+	}
+
+	messages := make([]model.Message, 0, len(po.Messages))
+	// model.Messages does not support plurals atm. But we plan to impl it under:
+	// https://github.com/orgs/translate-agent/projects/1?pane=issue&itemId=21251425
+	for _, node := range po.Messages {
+		if strings.HasSuffix(node.MsgId, "\\n") {
+			node.MsgId = strings.ReplaceAll(node.MsgId, "\\n", "\n")
+		}
+
+		if node.MsgIdPlural != "" {
+			continue
+		}
+
+		fuzzy := strings.Contains(node.Flag, "fuzzy")
+
+		message := model.Message{
+			ID:          node.MsgId,
+			Description: strings.Join(node.ExtractedComment, "\n"),
+			Fuzzy:       fuzzy,
+		}
+
+		if len(node.MsgStr) > 0 {
+			if strings.HasSuffix(node.MsgStr[0], "\\n") {
+				node.MsgStr[0] = strings.ReplaceAll(node.MsgStr[0], "\\n", "\n")
+			}
+
+			message.Message = node.MsgStr[0]
+		}
+
+		messages = append(messages, message)
+	}
+
+	return model.Messages{
+		Language: po.Header.Language,
+		Messages: messages,
+	}, nil
+}
+
+func writeToPoTag(b *bytes.Buffer, tag poTag, str string) error {
+	encodedStr, err := json.Marshal(str) // use JSON encoding to escape special characters
+	if err != nil {
+		return fmt.Errorf("marshal %s: %w", tag, err)
+	}
+
+	encodedStr = encodedStr[1 : len(encodedStr)-1] // trim quotes
+	lines := strings.Split(string(encodedStr), "\\n")
+
+	// Remove the empty string element. The line is empty when splitting by "\\n" and "\n" is the last character in str.
+	if lines[len(lines)-1] == "" {
+		lines = lines[:len(lines)-1]
+		lines[len(lines)-1] = lines[len(lines)-1] + "\\n" // add the "\n" back to the last line
+	}
+
+	if len(lines) == 1 {
+		_, err = fmt.Fprintf(b, "%s \"%s\"\n", tag, lines[0])
+		if err != nil {
+			return fmt.Errorf("write %s: %w", tag, err)
+		}
+
+		return nil
+	}
+
+	_, err = fmt.Fprintf(b, "%s \"\"\n", tag)
+	if err != nil {
+		return fmt.Errorf("write %s: %w", tag, err)
+	}
+
+	for _, line := range lines {
+		if strings.HasSuffix(line, "\\n") {
+			_, err = fmt.Fprint(b, "\""+line+"\""+"\n")
+			if err != nil {
+				return fmt.Errorf("write %s: %w", tag, err)
+			}
+		} else {
+			_, err = fmt.Fprint(b, "\""+line+"\\n\""+"\n")
+			if err != nil {
+				return fmt.Errorf("write %s: %w", tag, err)
+			}
+		}
+	}
+
+	return nil
+}