zettelkasten.nvim/lua/zettelkasten/link.lua

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local L = {}
local o = require 'zettelkasten.options'
local a = require 'zettelkasten.anchor'
-- Returns the text cleaned up to be more useful in a link.
-- Spaces are replaced by dashes and everything is lowercased.
function L.urlify(text)
text = text or ""
return text:lower():gsub(" ", "-")
end
-- Returns the untouched text with the extension set in options appended
-- at the end.
function L.append_extension(text) return text .. o.zettel().extension end
local function must_have(content)
if not content or content == "" then
error("Link is not allowed to be empty.")
end
end
-- Returns text with surrounding whitespace trimmed. Returns empty string
-- if only whitespace.
local function trimmed(text)
return text:match '^()%s*$' and '' or text:match '^%s*(.*%S)'
end
-- Returns a markdown-compatible transformation of the link and text combination
-- passed in.
function L.style_markdown(link, text)
must_have(link)
return "[" .. trimmed(text) .. "](" .. link .. ")"
end
-- Returns a wikilink-compatible transformation of the link and text combination
-- passed in, adding the text as a pipe if it exists.
function L.style_wiki(link, text)
must_have(link)
local pipe = ""
text = trimmed(text)
if text and text ~= "" then pipe = "|" .. text end
return "[[" .. link .. pipe .. "]]"
end
-- Returns a correctly formatted link to a new zettel.
-- Takes an optional link text which will be added to the link.
-- Takes an optional style according to which the link will be transformed.
function L.create(anchor, text, style)
style = style or o.zettel().link_style
if style == "markdown" then
local link = (a.prepend(anchor, L.urlify(text)))
return L.style_markdown(L.append_extension(link), text)
elseif style == "wiki" then
return L.style_wiki(anchor, text)
end
error("Link creation failed.")
end
return L