From f9c1b89608eccc5e11588052ea3c69d03b97e3f6 Mon Sep 17 00:00:00 2001
From: nxshock <nxshock@gmail.com>
Date: Sat, 9 Mar 2024 21:54:26 +0500
Subject: [PATCH] Add CSV+Zstandart export format

---
 export.go        |  3 ++
 export_csvzst.go | 81 ++++++++++++++++++++++++++++++++++++++++++++++++
 go.mod           |  1 +
 go.sum           |  2 ++
 ui_main_form.go  |  4 +--
 5 files changed, 89 insertions(+), 2 deletions(-)
 create mode 100644 export_csvzst.go

diff --git a/export.go b/export.go
index a904827..58a498e 100644
--- a/export.go
+++ b/export.go
@@ -10,6 +10,7 @@ const (
 	ExportFormatExcel  ExportFormat = "XLSX"
 	ExportFormatCsv    ExportFormat = "CSV"
 	ExportFormatCsvZip ExportFormat = "CSV+ZIP"
+	ExportFormatCsvZst ExportFormat = "CSV+ZSTD"
 )
 
 // Exporter - интерфейс экспорта
@@ -25,6 +26,8 @@ func (e ExportFormat) GetExporter(encoding Encoding) (Exporter, error) {
 		return &CsvExporter{Encoding: encoding}, nil
 	case ExportFormatCsvZip:
 		return &CsvZipExporter{Encoding: encoding}, nil
+	case ExportFormatCsvZst:
+		return &CsvZstExporter{Encoding: encoding}, nil
 	}
 
 	return nil, fmt.Errorf("unknown format: %s", string(e))
diff --git a/export_csvzst.go b/export_csvzst.go
new file mode 100644
index 0000000..cdd469a
--- /dev/null
+++ b/export_csvzst.go
@@ -0,0 +1,81 @@
+package main
+
+import (
+	"bufio"
+	"encoding/csv"
+	"os"
+
+	"github.com/klauspost/compress/zstd"
+)
+
+// Экспорт в CSV, сжатый в ZIP-архив
+type CsvZstExporter struct {
+	Encoding Encoding
+}
+
+func (c *CsvZstExporter) FileExt() string {
+	return ".csv.zst"
+}
+
+func (c *CsvZstExporter) Convert(filePath string, rows chan []any) error {
+	f, err := os.Create(filePath + c.FileExt())
+	if err != nil {
+		return err
+	}
+
+	buf := bufio.NewWriterSize(f, 4*1024*1024)
+
+	z, err := zstd.NewWriter(buf)
+	if err != nil {
+		f.Close()
+		return err
+	}
+
+	enc, err := c.Encoding.Encoder()
+	if err != nil {
+		return err
+	}
+
+	w := csv.NewWriter(enc.Writer(z))
+	w.Comma = ';'
+
+	rowNum := 0
+	for row := range rows {
+		rowNum++
+		rowsStr := make([]string, len(row))
+		for i := range row {
+			rowsStr[i] = toCsvField(row[i])
+		}
+
+		err = w.Write(rowsStr)
+		if err != nil {
+			f.Close()
+			return err
+		}
+	}
+
+	w.Flush()
+	if err = w.Error(); err != nil {
+		f.Close()
+		return err
+	}
+
+	err = z.Close()
+	if err != nil {
+		f.Close()
+		return err
+	}
+
+	err = buf.Flush()
+	if err != nil {
+		f.Close()
+		return err
+	}
+
+	err = f.Close()
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
diff --git a/go.mod b/go.mod
index da376c2..3abcd8e 100644
--- a/go.mod
+++ b/go.mod
@@ -12,6 +12,7 @@ require (
 )
 
 require (
+	github.com/klauspost/compress v1.17.7 // indirect
 	github.com/mohae/deepcopy v0.0.0-20170929034955-c48cc78d4826 // indirect
 	github.com/richardlehane/mscfb v1.0.4 // indirect
 	github.com/richardlehane/msoleps v1.0.3 // indirect
diff --git a/go.sum b/go.sum
index 39eb6ff..63fa4cd 100644
--- a/go.sum
+++ b/go.sum
@@ -5,6 +5,8 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dimchansky/utfbom v1.1.1 h1:vV6w1AhK4VMnhBno/TPVCoK9U/LP0PkLCS9tbxHdi/U=
 github.com/dimchansky/utfbom v1.1.1/go.mod h1:SxdoEBH5qIqFocHMyGOXVAybYJdr71b1Q/j0mACtrfE=
+github.com/klauspost/compress v1.17.7 h1:ehO88t2UGzQK66LMdE8tibEd1ErmzZjNEqWkjLAKQQg=
+github.com/klauspost/compress v1.17.7/go.mod h1:Di0epgTjJY877eYKx5yC51cX2A2Vl2ibi7bDH9ttBbw=
 github.com/mohae/deepcopy v0.0.0-20170929034955-c48cc78d4826 h1:RWengNIwukTxcDr9M+97sNutRR1RKhG96O6jWumTTnw=
 github.com/mohae/deepcopy v0.0.0-20170929034955-c48cc78d4826/go.mod h1:TaXosZuwdSHYgviHp1DAtfrULt5eUgsSMsZf+YrPgl8=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
diff --git a/ui_main_form.go b/ui_main_form.go
index 4353a8c..851b0e3 100644
--- a/ui_main_form.go
+++ b/ui_main_form.go
@@ -246,7 +246,7 @@ func (f *TMainForm) OnFormCreate(sender vcl.IObject) {
 	// -------------------------------------------------------------------------
 
 	// File formats ------------------------------------------------------------
-	for _, v := range []string{string(ExportFormatExcel), string(ExportFormatCsv), string(ExportFormatCsvZip)} {
+	for _, v := range []string{string(ExportFormatExcel), string(ExportFormatCsv), string(ExportFormatCsvZip), string(ExportFormatCsvZst)} {
 		f.ExportFormatComboBox.Items().Add(v)
 	}
 	f.ExportFormatComboBox.SetItemIndex(0)
@@ -322,7 +322,7 @@ func (f *TMainForm) OnLaunchButtonClick(sender vcl.IObject) {
 }
 
 func (f *TMainForm) OnExportFormatComboBoxChange(sender vcl.IObject) {
-	if slices.Contains([]string{string(ExportFormatCsv), string(ExportFormatCsvZip)}, f.ExportFormatComboBox.Text()) {
+	if slices.Contains([]string{string(ExportFormatCsv), string(ExportFormatCsvZip), string(ExportFormatCsvZst)}, f.ExportFormatComboBox.Text()) {
 		f.CharsetComboBox.SetEnabled(true)
 	} else {
 		f.CharsetComboBox.SetEnabled(false)