Parse date title to actual date

file.go

@@ -131,7 +131,6 @@ type titleOption struct {
 	timeObj time.Time
 }
 
-
 // 1_januari_2021
 // 2021-01-01
 
@@ -139,29 +138,33 @@ func (fp *FilePages) Get(name string) Page {
 	var sw stopwatch
 	sw.Start("Get " + name)
 	defer sw.Stop()
-
 	var names []string
-	date := false
-	t, err := time.Parse("2006-01-02", name)
+
+	var to titleOption
+	pageNameDate, err := ParseDatePageName(name)
 	if err == nil {
-		date = true
-		names = append(names, formatDatePageName(t), name)
+		to.date = true
+		to.timeObj = pageNameDate
+		names = append(names, name, pageNameDate.Format("2006-01-02"))
+	} else if t, err := time.Parse("2006-01-02", name); err == nil {
+		to.date = true
+		to.timeObj = t
+		names = append(names, formatDatePageName(to.timeObj), name)
 	} else {
 		names = append(names, name)
 	}
 
 	for _, name := range names {
-		log.Printf("Trying %q", name)
 		blocks, err := loadBlocks(fp.dirname, name)
 		if err != nil && errors.Is(err, BlockNotFound) {
 			continue
 		}
-		return fp.blocksBackendGet(name, blocks, titleOption{date, t})
+		return fp.blocksBackendGet(name, blocks, to)
 	}
 
 	page, err := fp.oldPagesBackend(name)
 	if err != nil {
-		return fp.blocksBackendGet(name, BlockResponse{ParentID: "root", PageID: name}, titleOption{date, t})
+		return fp.blocksBackendGet(name, BlockResponse{ParentID: "root", PageID: name}, to)
 	}
 
 	return page

util.go

@@ -3,16 +3,35 @@ package main
 import (
 	"bufio"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"log"
 	"math/rand"
 	"regexp"
+	"strconv"
 	"strings"
 	"time"
 )
 
 var (
-	MetaKV = regexp.MustCompile(`(\w+)::\s+(.*)`)
+	MetaKV          = regexp.MustCompile(`(\w+)::\s+(.*)`)
+	niceDateParseRE = regexp.MustCompile(`^(\d{1,2})_([a-z]+)_(\d{4})$`)
+	ParseFailed     = errors.New("parse failed")
+	Months          = []string{
+		"",
+		"januari",
+		"februari",
+		"maart",
+		"april",
+		"mei",
+		"juni",
+		"juli",
+		"augustus",
+		"september",
+		"oktober",
+		"november",
+		"december",
+	}
 )
 
 type ParsedLink struct {
@@ -103,40 +122,10 @@ func todayPage() string {
 }
 
 func formatDateTitle(date time.Time) string {
-	months := []string{
-		"",
-		"januari",
-		"februari",
-		"maart",
-		"april",
-		"mei",
-		"juni",
-		"juli",
-		"augustus",
-		"september",
-		"oktober",
-		"november",
-		"december",
-	}
-	return fmt.Sprintf("%d %s %d", date.Day(), months[date.Month()], date.Year())
+	return fmt.Sprintf("%d %s %d", date.Day(), Months[date.Month()], date.Year())
 }
 func formatDatePageName(date time.Time) string {
-	months := []string{
-		"",
-		"januari",
-		"februari",
-		"maart",
-		"april",
-		"mei",
-		"juni",
-		"juli",
-		"augustus",
-		"september",
-		"oktober",
-		"november",
-		"december",
-	}
-	return fmt.Sprintf("%d_%s_%d", date.Day(), months[date.Month()], date.Year())
+	return fmt.Sprintf("%d_%s_%d", date.Day(), Months[date.Month()], date.Year())
 }
 
 func PageTitle(pageText string) (string, error) {
@@ -158,3 +147,31 @@ func PageTitle(pageText string) (string, error) {
 	}
 	return "", fmt.Errorf("no meta title found in page text")
 }
+
+func parseMonth(month string) (time.Month, error) {
+	for i, m := range Months {
+		if m == month {
+			return time.Month(i), nil
+		}
+	}
+	return time.Month(0), fmt.Errorf("parseMonth: %q is not a recognized month", month)
+}
+
+func ParseDatePageName(name string) (time.Time, error) {
+	if matches := niceDateParseRE.FindStringSubmatch(name); matches != nil {
+		day, err := strconv.Atoi(matches[1])
+		if err != nil {
+			return time.Time{}, fmt.Errorf("%q: %s: %w", name, err, ParseFailed)
+		}
+		month, err := parseMonth(matches[2])
+		if err != nil {
+			return time.Time{}, fmt.Errorf("%q: %s: %w", name, err, ParseFailed)
+		}
+		year, err := strconv.Atoi(matches[3])
+		if err != nil {
+			return time.Time{}, fmt.Errorf("%q: %s: %w", name, err, ParseFailed)
+		}
+		return time.Date(year, month, day, 0, 0, 0, 0, time.Local), nil
+	}
+	return time.Time{}, fmt.Errorf("%q: invalid syntax: %w", name, ParseFailed)
+}