CC-Tweaked/src/main/resources/data/computercraft/lua/rom/apis/help.lua

111 lines
3.2 KiB
Lua

--- Provides an API to read help files.
--
-- @module help
local expect = dofile("rom/modules/main/cc/expect.lua").expect
local sPath = "/rom/help"
--- Returns a colon-separated list of directories where help files are searched
-- for. All directories are absolute.
--
-- @treturn string The current help search path, separated by colons.
-- @see help.setPath
function path()
return sPath
end
--- Sets the colon-seperated list of directories where help files are searched
-- for to `newPath`
--
-- @tparam string newPath The new path to use.
-- @usage help.setPath( "/disk/help/" )
-- @usage help.setPath( help.path() .. ":/myfolder/help/" )
-- @see help.path
function setPath(_sPath)
expect(1, _sPath, "string")
sPath = _sPath
end
local extensions = { "", ".md", ".txt" }
--- Returns the location of the help file for the given topic.
--
-- @tparam string topic The topic to find
-- @treturn string|nil The path to the given topic's help file, or `nil` if it
-- cannot be found.
-- @usage help.lookup("disk")
function lookup(topic)
expect(1, topic, "string")
-- Look on the path variable
for path in string.gmatch(sPath, "[^:]+") do
path = fs.combine(path, topic)
for _, extension in ipairs(extensions) do
local file = path .. extension
if fs.exists(file) and not fs.isDir(file) then
return file
end
end
end
-- Not found
return nil
end
--- Returns a list of topics that can be looked up and/or displayed.
--
-- @treturn table A list of topics in alphabetical order.
-- @usage help.topics()
function topics()
-- Add index
local tItems = {
["index"] = true,
}
-- Add topics from the path
for sPath in string.gmatch(sPath, "[^:]+") do
if fs.isDir(sPath) then
local tList = fs.list(sPath)
for _, sFile in pairs(tList) do
if string.sub(sFile, 1, 1) ~= "." then
if not fs.isDir(fs.combine(sPath, sFile)) then
for i = 2, #extensions do
local extension = extensions[i]
if #sFile > #extension and sFile:sub(-#extension) == extension then
sFile = sFile:sub(1, -#extension - 1)
end
end
tItems[sFile] = true
end
end
end
end
end
-- Sort and return
local tItemList = {}
for sItem in pairs(tItems) do
table.insert(tItemList, sItem)
end
table.sort(tItemList)
return tItemList
end
--- Returns a list of topic endings that match the prefix. Can be used with
-- `read` to allow input of a help topic.
--
-- @tparam string prefix The prefix to match
-- @treturn table A list of matching topics.
function completeTopic(sText)
expect(1, sText, "string")
local tTopics = topics()
local tResults = {}
for n = 1, #tTopics do
local sTopic = tTopics[n]
if #sTopic > #sText and string.sub(sTopic, 1, #sText) == sText then
table.insert(tResults, string.sub(sTopic, #sText + 1))
end
end
return tResults
end