From 0b2443c720c962dbd1f5730c40e4a5d52f051a23 Mon Sep 17 00:00:00 2001
From: Nick Dumas <nobodys@business.com>
Date: Tue, 7 Feb 2023 19:11:21 +0000
Subject: [PATCH] passing tests

---
 go.mod       |  2 +-
 main.go      | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 main_test.go | 34 +++++++++++++++++++++++++++++++++
 test-cases   | 10 ++++++++++
 4 files changed, 99 insertions(+), 1 deletion(-)
 create mode 100644 main.go
 create mode 100644 main_test.go
 create mode 100644 test-cases

diff --git a/go.mod b/go.mod
index 016c362..4865887 100644
--- a/go.mod
+++ b/go.mod
@@ -1,3 +1,3 @@
-module github.com/therealfakemoot/wikilinks-parser
+module wikilinks
 
 go 1.19
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..2f35d93
--- /dev/null
+++ b/main.go
@@ -0,0 +1,54 @@
+package main
+
+import (
+	"log"
+	"regexp"
+)
+
+var (
+	alias      = regexp.MustCompile(`\|(.*)`)
+	link       = regexp.MustCompile(`^([a-zA-Z ]+)?[\|\#\^\\]?`)
+	subsection = regexp.MustCompile(`#([\w\s]+)`)
+	block      = regexp.MustCompile(`#\^([a-zA-Z ]+)`)
+	wholeLink  = regexp.MustCompile(`\[\[(.*)\]\]`)
+)
+
+type Link struct {
+	Dest, Alias, Subsection, Block string
+}
+
+func ExtractLink(raw string) Link {
+	var li Link
+
+	rawLinkMatch := wholeLink.FindAllStringSubmatch(raw, -1)
+	var rawLink string
+	if len(rawLinkMatch) > 0 {
+		rawLink = rawLinkMatch[0][1]
+	}
+
+	l := link.FindAllStringSubmatch(rawLink, -1)
+	if len(l) > 0 {
+		li.Dest = l[0][1]
+	}
+
+	a := alias.FindAllStringSubmatch(rawLink, -1)
+	if len(a) > 0 {
+		li.Alias = a[0][1]
+	}
+
+	s := subsection.FindAllStringSubmatch(rawLink, -1)
+	if len(s) > 0 {
+		li.Subsection = s[0][1]
+	}
+
+	b := block.FindAllStringSubmatch(rawLink, -1)
+	if len(b) > 0 {
+		li.Block = b[0][1]
+	}
+
+	return li
+}
+
+func main() {
+	log.Printf("%#v\n", ExtractLink(`Embedding a link in a bigger block of text [[Regular Link#^link to block]] shouldn't cause any problems `))
+}
diff --git a/main_test.go b/main_test.go
new file mode 100644
index 0000000..38c3b20
--- /dev/null
+++ b/main_test.go
@@ -0,0 +1,34 @@
+package main
+
+import (
+	"testing"
+)
+
+func Test_ExtractLink(t *testing.T) {
+	tcs := []struct {
+		name     string
+		in       string
+		expected Link
+	}{
+		{"link", `[[Regular Link]]`, Link{Dest: "Regular Link"}},
+		{"transclude+link", `![[Transcluded Link]]`, Link{Dest: "Transcluded Link"}},
+		{"link+alias", `[[Regular Link|Alias]]`, Link{Dest: "Regular Link", Alias: "Alias"}},
+		{"link+subsection", `[[Regular Link#Subsection of page]]`, Link{Dest: "Regular Link", Subsection: "Subsection of page"}},
+		{"link+block", `[[Regular Link#^link to block]]`, Link{Dest: "Regular Link", Block: "link to block"}},
+		{"link+subsection+alias", `[[Regular Link#Subsection of page|Alias]]`, Link{Dest: "Regular Link", Subsection: "Subsection of page", Alias: "Alias"}},
+		{"link+block+alias", `[[Regular Link#^link to block|Alias]]`, Link{Dest: "Regular Link", Block: "link to block", Alias: "Alias"}},
+		{"link+alias+escape", `[[Regular Link\|Alias]]`, Link{Dest: "Regular Link", Alias: "Alias"}},
+		{"link+subsection+alias+escape", `[[Regular Link#Subsection of page\|Alias]]`, Link{Dest: "Regular Link", Subsection: "Subsection of page", Alias: "Alias"}},
+		{"link+block+alias+escape", `[[Regular Link#^link to block\|Alias]]`, Link{Dest: "Regular Link", Block: "link to block", Alias: "Alias"}},
+	}
+
+	for _, tc := range tcs {
+		t.Run(tc.name, func(t *testing.T) {
+			out := ExtractLink(tc.in)
+			if out != tc.expected {
+				t.Logf("got %#v\n", out)
+				t.Fail()
+			}
+		})
+	}
+}
diff --git a/test-cases b/test-cases
new file mode 100644
index 0000000..20b4d5f
--- /dev/null
+++ b/test-cases
@@ -0,0 +1,10 @@
+[[Regular Link]]
+![[Transcluded Link]]
+[[Regular Link|Alias]]
+[[Regular Link#Subsection of page]]
+[[Regular Link^link to block]]
+[[Regular Link#Subsection of page|Alias]]
+[[Regular Link^link to block|Alias]]
+[[Regular Link\|Alias]]
+[[Regular Link#Subsection of page\|Alias]]
+[[Regular Link^link to block\|Alias]]