From 0197cee9a2145be5867e22c4d7841a113464e165 Mon Sep 17 00:00:00 2001
From: Peter Stuifzand <peter@stuifzand.eu>
Date: Sun, 19 Jul 2020 17:10:59 +0200
Subject: [PATCH] Replace title from the contents of the page

---
 main.go | 40 ++++++++++++++++++++++++++--------------
 util.go | 25 +++++++++++++++++++++++++
 2 files changed, 51 insertions(+), 14 deletions(-)

diff --git a/main.go b/main.go
index 0e6c447..892f8cb 100644
--- a/main.go
+++ b/main.go
@@ -443,10 +443,15 @@ func (h *editHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 
 	pageBase := getPageBase()
+	title := cleanTitle(page)
+	if newTitle, err := PageTitle(pageText); err == nil {
+		title = newTitle
+	}
+
 	data := editPage{
 		pageBaseInfo: pageBase,
 		Session:      sess,
-		Title:        cleanTitle(page),
+		Title:        title,
 		Content:      pageText,
 		Editor:       editor,
 		Name:         page,
@@ -551,6 +556,11 @@ func (h *graphHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 func (h *indexHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	defer r.Body.Close()
 
+	metaKV, err := regexp.Compile(`(\w+)::\s+(.*)`)
+	if err != nil {
+		log.Fatal(err)
+	}
+
 	sess, err := NewSession(w, r)
 	if err != nil {
 		http.Error(w, err.Error(), 500)
@@ -595,6 +605,8 @@ func (h *indexHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	var rawMsg json.RawMessage
 	err = json.NewDecoder(strings.NewReader(pageText)).Decode(&rawMsg)
 
+	title := cleanTitle(page)
+
 	jsonPage := pageText != "" && err == nil
 	if jsonPage {
 		var listItems []struct {
@@ -627,6 +639,11 @@ func (h *indexHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 					}
 				}
 			} else {
+				if matches := metaKV.FindStringSubmatch(item.Text); matches != nil {
+					if matches[1] == "Title" {
+						title = matches[2]
+					}
+				}
 				builder.WriteString(strings.Repeat("  ", item.Indented))
 				builder.WriteString("* ")
 				builder.WriteString(item.Text)
@@ -637,10 +654,6 @@ func (h *indexHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	}
 
 	if format == "html" {
-		metaKV, err := regexp.Compile(`(\w+)::\s+(.*)`)
-		if err != nil {
-			log.Fatal(err)
-		}
 		pageText = metaKV.ReplaceAllString(pageText, "**[[$1]]**: $2")
 
 		pageText = renderLinks(pageText, false)
@@ -650,7 +663,7 @@ func (h *indexHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		data := indexPage{
 			pageBaseInfo: pageBase,
 			Session:      sess,
-			Title:        cleanTitle(page),
+			Title:        title,
 			Content:      template.HTML(pageText),
 			Name:         page,
 			Backrefs:     mpPage.Refs,
@@ -671,7 +684,7 @@ func (h *indexHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		}
 	} else if format == "markdown" {
 		_, err = io.WriteString(w, "# ")
-		_, err = io.WriteString(w, cleanTitle(page))
+		_, err = io.WriteString(w, title)
 		_, err = io.WriteString(w, "\n\n")
 		_, err = io.WriteString(w, pageText)
 	}
@@ -811,19 +824,18 @@ func main() {
 		http.ServeFile(w, r, filepath.Join(dataDir, LinksFile))
 	})
 	http.HandleFunc("/api/graph", func(w http.ResponseWriter, r *http.Request) {
-		name := r.URL.Query().Get("name")
-
 		gb, err := NewGraphBuilder(mp)
 		if err != nil {
 			http.Error(w, err.Error(), 500)
 			return
 		}
-		gb.RemoveNode(name)
 
-		err = gb.buildFromCenter(name)
-		if err != nil {
-			http.Error(w, err.Error(), 500)
-			return
+		for _, name := range r.URL.Query()["name"] {
+			err = gb.buildFromCenter(name)
+			if err != nil {
+				http.Error(w, err.Error(), 500)
+				return
+			}
 		}
 
 		// Keep a copy of the nodes, buildFromCenter appends to the nodeMap
diff --git a/util.go b/util.go
index 306aad5..702ab4f 100644
--- a/util.go
+++ b/util.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"bufio"
+	"encoding/json"
 	"fmt"
 	"log"
 	"math/rand"
@@ -10,6 +11,10 @@ import (
 	"time"
 )
 
+var (
+	MetaKV = regexp.MustCompile(`(\w+)::\s+(.*)`)
+)
+
 type ParsedLink struct {
 	ID       string `json:"ID"`
 	Name     string
@@ -116,3 +121,23 @@ func todayPage() string {
 	}
 	return fmt.Sprintf("%d_%s_%d", now.Day(), months[now.Month()], now.Year())
 }
+
+func PageTitle(pageText string) (string, error) {
+	var listItems []struct {
+		Indented int
+		Text     string
+	}
+	err := json.NewDecoder(strings.NewReader(pageText)).Decode(&listItems)
+	if err != nil {
+		return "", fmt.Errorf("while decoding page text: %w", err)
+	}
+
+	for _, li := range listItems {
+		if matches := MetaKV.FindStringSubmatch(li.Text); matches != nil {
+			if matches[1] == "Title" {
+				return matches[2], nil
+			}
+		}
+	}
+	return "", fmt.Errorf("no meta title found in page text")
+}