From 0d9a677acac9bd7c3c8b460a67897a9b844f4393 Mon Sep 17 00:00:00 2001
From: Dan Konshin <konshin104@gmail.com>
Date: Sun, 5 Jul 2020 19:56:03 +0500
Subject: [PATCH] Gemini parser

---
 plugin/parser/gemini.go        | 70 +++++++++++++++++++++++++++++++++-
 plugin/parser/toHtml.go        | 53 +++++++++++++++++++++++++
 wiki/main/testgemini/1.txt     | 25 ++++++++++++
 wiki/main/testgemini/meta.json | 17 +++++++++
 4 files changed, 163 insertions(+), 2 deletions(-)
 create mode 100644 plugin/parser/toHtml.go
 create mode 100644 wiki/main/testgemini/1.txt
 create mode 100644 wiki/main/testgemini/meta.json

diff --git a/plugin/parser/gemini.go b/plugin/parser/gemini.go
index 68dbb26..5520109 100644
--- a/plugin/parser/gemini.go
+++ b/plugin/parser/gemini.go
@@ -1,7 +1,73 @@
 package parser
 
-import ()
+import (
+	"bytes"
+	"strings"
+
+	"github.com/bouncepaw/mycorrhiza/util"
+)
+
+const (
+	linkToken         = "=>"
+	headerToken       = "#"
+	quoteToken        = ">"
+	preformattedToken = "```"
+	listItemToken     = "*"
+)
 
 func GeminiToHtml(gemini []byte) string {
-	return ""
+	lines, _ := StringToLines(string(util.NormalizeEOL(gemini)))
+	var html []string
+	for _, line := range lines {
+		html = append(html, geminiLineToHtml(line))
+	}
+	buffer := bytes.Buffer{}
+	for _, line := range html {
+		buffer.WriteString(line)
+	}
+	return buffer.String()
+}
+
+func geminiLineToHtml(line string) (res string) {
+	arr := strings.Fields(line)
+	if len(arr) == 0 {
+		return lineBreak
+	}
+
+	content := arr[1:]
+	token := arr[0]
+	if string(token[0]) == headerToken {
+		return makeHeader(makeOutHeader(arr))
+	}
+
+	switch token {
+	case linkToken:
+		res = makeLink(makeOutLink(content))
+	case quoteToken:
+		res = makeBlockQuote(LinesToString(content, " "))
+	case preformattedToken:
+		res = makePreformatted(LinesToString(content, " "))
+	case listItemToken:
+		res = makeListItem(LinesToString(content, " "))
+	default:
+		res = makeParagraph(line)
+	}
+	return res
+}
+
+func makeOutLink(arr []string) (source, content string) {
+	switch len(arr) {
+	case 0:
+		return "", ""
+	case 1:
+		return arr[0], arr[0]
+	default:
+		return arr[0], LinesToString(arr[1:], " ")
+	}
+}
+
+func makeOutHeader(arr []string) (level int, content string) {
+	level = len(arr[0])
+	content = LinesToString(arr[1:], " ")
+	return
 }
diff --git a/plugin/parser/toHtml.go b/plugin/parser/toHtml.go
new file mode 100644
index 0000000..f6be2b5
--- /dev/null
+++ b/plugin/parser/toHtml.go
@@ -0,0 +1,53 @@
+package parser
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"strings"
+)
+
+const (
+	lineBreak = "<br>"
+)
+
+func makeLink(source, content string) string {
+	return fmt.Sprintf(`<a href="%v">%v</a>`, source, content)
+}
+
+func makeParagraph(content string) string {
+	return `<p>` + content + `</p>`
+}
+
+func makeBlockQuote(content string) string {
+	return `<blockquote>` + content + `</blockquote>`
+}
+
+func makeHeader(level int, content string) string {
+	return fmt.Sprintf("<h%v>%v</h%v>", level, content, level)
+}
+
+func makePreformatted(content string) string {
+	return "<pre>" + content + "</pre>"
+}
+
+func makeListItem(content string) string {
+	return "<li>" + content + "</li>"
+}
+
+func StringToLines(s string) (lines []string, err error) {
+	scanner := bufio.NewScanner(strings.NewReader(s))
+	for scanner.Scan() {
+		lines = append(lines, scanner.Text())
+	}
+	err = scanner.Err()
+	return
+}
+
+func LinesToString(lines []string, separator string) string {
+	buffer := bytes.Buffer{}
+	for _, line := range lines {
+		buffer.WriteString(line + separator)
+	}
+	return buffer.String()
+}
diff --git a/wiki/main/testgemini/1.txt b/wiki/main/testgemini/1.txt
new file mode 100644
index 0000000..c03e6f3
--- /dev/null
+++ b/wiki/main/testgemini/1.txt
@@ -0,0 +1,25 @@
+# Gemtext cheatsheet
+Here's the basics of how text works in Gemtext:
+
+Long lines get wrapped by the client to fit the screen
+Short lines *don't* get joined together
+Write paragraphs as single long lines
+Blank lines are rendered verbatim
+You get three levels of heading:
+
+# Heading
+## Sub-heading
+### Sub-subheading
+You get one kind of list and you can't nest them:
+
+* Mercury
+* Gemini
+* Apollo
+Here's a quote                  from Maciej Cegłowski:
+
+> I contend that text-based websites should not exceed in size the      major works of Russian literature.
+Lines which start with ``` will cause clients to toggle in and out of ordinary rendering mode and preformatted mode. In preformatted mode, Gemtext syntax is ignored so links etc. will not be rendered, and text will appear in a monospace font.
+``` =>https://not-a-href.com preformatted
+
+=> https://proxy.vulpes.one/gemini/gemini.circumlunar.space/docs/cheatsheet.gmi Original cheatsheet
+=> https://proxy.vulpes.one/gemini/gemini.circumlunar.space/docs/cheatsheet.gmi
diff --git a/wiki/main/testgemini/meta.json b/wiki/main/testgemini/meta.json
new file mode 100644
index 0000000..82e4bf3
--- /dev/null
+++ b/wiki/main/testgemini/meta.json
@@ -0,0 +1,17 @@
+{
+	"views": 0,
+	"deleted": false,
+	"revisions": {
+		"1": {
+			"tags": null,
+			"name": "Testgemini",
+			"comment": "Create :Main/Testgemini",
+			"author": "",
+			"time": 1593960824,
+			"text_mime": "text/gemini",
+			"binary_mime": "",
+			"text_name": "1.txt",
+			"binary_name": ""
+		}
+	}
+}
\ No newline at end of file