:art: Clean code

kernel/model/export.go

@@ -20,7 +20,6 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
-	"github.com/Masterminds/sprig/v3"
 	"net/http"
 	"net/url"
 	"os"
@@ -41,7 +40,9 @@ import (
 	"github.com/88250/lute/parse"
 	"github.com/88250/lute/render"
 	"github.com/88250/pdfcpu/pkg/api"
+	"github.com/88250/pdfcpu/pkg/font"
 	"github.com/88250/pdfcpu/pkg/pdfcpu"
+	"github.com/Masterminds/sprig/v3"
 	"github.com/emirpasic/gods/sets/hashset"
 	"github.com/emirpasic/gods/stacks/linkedliststack"
 	"github.com/imroc/req/v3"
@@ -994,11 +995,23 @@ func processPDFFooter(pdfCtx *pdfcpu.Context) {
 	}
 	footer := buf.String()
 
-	fontName := "Times-Roman"
+	fontName := "Helvetica"
+	names := font.UserFontNames()
+	if 1 > len(names) {
+		preferredFont := util.GetPreferredFontFilePath(Conf.Lang)
+		if err = api.InstallFonts([]string{preferredFont.Path}); nil != err {
+			logging.LogErrorf("install font failed: %s", err)
+		} else {
+			names = font.UserFontNames()
+			logging.LogInfof("install pdf font: %s", names)
+		}
+	}
+	if 0 < len(names) {
+		fontName = names[0]
+	}
+
 	pos := "bc"
-	dx := 10
-	fillCol := "#000000"
-	desc := fmt.Sprintf("font:%s, points:12, sc:1 abs, pos:%s, off:%d 10, fillcol:%s, rot:0", fontName, pos, dx, fillCol)
+	desc := fmt.Sprintf("font:%s, points:8, sc:1 abs, pos:%s, off:10 10, fillc: 0.5 0.5 0.5, rot:0", fontName, pos)
 	footer = strings.ReplaceAll(footer, "%pages", strconv.Itoa(pdfCtx.PageCount))
 	m := map[int]*pdfcpu.Watermark{}
 	for i := 1; i <= pdfCtx.PageCount; i++ {

kernel/util/font.go

@@ -30,9 +30,28 @@ import (
 	"golang.org/x/text/transform"
 )
 
+var (
+	preferredFonts = []string{"Microsoft YaHei", "SimSun", "微软雅黑", "宋体", "仿宋", "Helvetica Neue", "Luxi Sans", "DejaVu Sans", "sans-serif", "Arial"}
+)
+
+func GetPreferredFontFilePath(currentLanguage string) *Font {
+	fonts := loadFonts(currentLanguage)
+	sort.Slice(fonts, func(i, j int) bool { return len(fonts[i].Family) > len(fonts[j].Family) })
+	for _, font := range fonts {
+		if gulu.Str.Contains(font.Family, preferredFonts) {
+			return font
+		}
+	}
+	return nil
+}
+
 func GetSysFonts(currentLanguage string) (ret []string) {
 	fonts := loadFonts(currentLanguage)
-	ret = gulu.Str.RemoveDuplicatedElem(fonts)
+	ret = []string{}
+	for _, font := range fonts {
+		ret = append(ret, font.Family)
+	}
+	ret = gulu.Str.RemoveDuplicatedElem(ret)
 	ret = removeUnusedFonts(ret)
 	sort.Strings(ret)
 	return
@@ -49,47 +68,52 @@ func removeUnusedFonts(fonts []string) (ret []string) {
 	return
 }
 
-func loadFonts(currentLanguage string) (ret []string) {
-	ret = []string{}
-	for _, f := range findfont.List() {
-		if strings.HasSuffix(strings.ToLower(f), ".ttc") {
-			data, err := os.ReadFile(f)
+type Font struct {
+	Path   string
+	Family string
+}
+
+func loadFonts(currentLanguage string) (ret []*Font) {
+	ret = []*Font{}
+	for _, fontPath := range findfont.List() {
+		if strings.HasSuffix(strings.ToLower(fontPath), ".ttc") {
+			data, err := os.ReadFile(fontPath)
 			if nil != err {
-				logging.LogErrorf("read font file [%s] failed: %s", f, err)
+				logging.LogErrorf("read font file [%s] failed: %s", fontPath, err)
 				continue
 			}
 			collection, err := ttc.ParseCollection(data)
 			if nil != err {
-				//LogErrorf("parse font collection [%s] failed: %s", f, err)
+				//LogErrorf("parse font collection [%s] failed: %s", fontPath, err)
 				continue
 			}
 
 			for i := 0; i < collection.NumFonts(); i++ {
 				font, err := collection.Font(i)
 				if nil != err {
-					//LogErrorf("get font [%s] failed: %s", f, err)
+					//LogErrorf("get font [%s] failed: %s", fontPath, err)
 					continue
 				}
 				if family := parseFontFamily(font); "" != family {
-					ret = append(ret, family)
-					//LogInfof("[%s] [%s]", f, family)
+					ret = append(ret, &Font{fontPath, family})
+					//LogInfof("[%s] [%s]", fontPath, family)
 				}
 			}
-		} else if strings.HasSuffix(strings.ToLower(f), ".otf") || strings.HasSuffix(strings.ToLower(f), ".ttf") {
-			fontFile, err := os.Open(f)
+		} else if strings.HasSuffix(strings.ToLower(fontPath), ".otf") || strings.HasSuffix(strings.ToLower(fontPath), ".ttf") {
+			fontFile, err := os.Open(fontPath)
 			if nil != err {
-				//LogErrorf("open font file [%s] failed: %s", f, err)
+				//LogErrorf("open font file [%s] failed: %s", fontPath, err)
 				continue
 			}
 			font, err := sfnt.Parse(fontFile)
 			if nil != err {
-				//LogErrorf("parse font [%s] failed: %s", f, err)
+				//LogErrorf("parse font [%s] failed: %s", fontPath, err)
 				continue
 			}
 
 			t, err := font.NameTable()
 			if nil != err {
-				//LogErrorf("parse font name table [%s] failed: %s", f, err)
+				//LogErrorf("parse font name table [%s] failed: %s", fontPath, err)
 				return
 			}
 			fontFile.Close()
@@ -102,7 +126,7 @@ func loadFonts(currentLanguage string) (ret []string) {
 				if sfnt.PlatformLanguageID(1033) == e.LanguageID {
 					v, _, err := transform.Bytes(textUnicode.UTF16(textUnicode.BigEndian, textUnicode.IgnoreBOM).NewDecoder(), e.Value)
 					if nil != err {
-						//LogErrorf("decode font family [%s] failed: %s", f, err)
+						//LogErrorf("decode font family [%s] failed: %s", fontPath, err)
 						continue
 					}
 					val := string(v)
@@ -119,7 +143,7 @@ func loadFonts(currentLanguage string) (ret []string) {
 
 					v, _, err := transform.Bytes(textUnicode.UTF16(textUnicode.BigEndian, textUnicode.IgnoreBOM).NewDecoder(), e.Value)
 					if nil != err {
-						//LogErrorf("decode font family [%s] failed: %s", f, err)
+						//LogErrorf("decode font family [%s] failed: %s", fontPath, err)
 						continue
 					}
 					val := string(v)
@@ -132,12 +156,12 @@ func loadFonts(currentLanguage string) (ret []string) {
 				}
 			}
 			if "" != family && !strings.HasPrefix(family, ".") {
-				ret = append(ret, family)
-				//LogInfof("[%s] [%s]", f, family)
+				ret = append(ret, &Font{fontPath, family})
+				//LogInfof("[%s] [%s]", fontPath, family)
 			}
 			if "" != familyChinese && !strings.HasPrefix(familyChinese, ".") {
-				ret = append(ret, familyChinese)
-				//LogInfof("[%s] [%s]", f, family)
+				ret = append(ret, &Font{fontPath, familyChinese})
+				//LogInfof("[%s] [%s]", fontPath, family)
 			}
 		}
 	}