#!/usr/bin/env luajit

-- Read the README file for what this is all about.  If there is no README or similar, then you can find the link to the source below.

local lunamark = require("lunamark")	-- https://github.com/jgm/lunamark

local opts = {
    layout='compact',
-- This list is copied from the lunamark source code, until I discover a way to discover it.  The descriptions are useful to.
    containers=false,            -- Put sections in containers (e.g. div or section tags)
    slides=false,                -- Like containers, but do not nest them
    startnum=true,               -- Start number of an ordered list is significant
    smart=false,                 -- Smart typography (quotes, dashes, ellipses)
    preserve_tabs=true,          -- Don't expand tabs to spaces
    notes=true,                  -- Footnotes
    inline_notes=true,           -- Inline footnotes
    definition_lists=true,       -- Definition lists
    citations=true,              -- Citations
    citation_nbsps=true,         -- Turn spacing into non-breaking spaces in citations
    fenced_code_blocks=true,     -- Fenced code blocks
    lua_metadata=true,           -- Lua metadata
    pandoc_title_blocks=true,    -- Pandoc style title blocks
    hash_enumerators=true,       -- may be used as ordered list enumerator
    require_blank_before_blockquote=false,
    require_blank_before_header=false,
    require_blank_before_fenced_code_block=false,
    fancy_lists=true,            -- Pandoc style fancy lists
    task_list=true,              -- GitHub-Flavored Markdown task list
    strikeout=true,              -- Strike-through with double tildes
    mark=true,                   -- Highlight with double equals
    subscript=true,              -- Subscripted text between tildes
    superscript=true,            -- Superscripted text between circumflexes
    bracketed_spans=true,        -- Spans with attributes
    fenced_divs=true,            -- Divs with attributes
    raw_attribute=true,          -- Raw pass-through on code elements
    fenced_code_attributes=true, -- Fenced code block attributes
    link_attributes=true,        -- Link attributes
    pipe_tables=true,            -- PHP Markdown Extra pipe table support
    table_captions=true,         -- Table caption syntax extension
    header_attributes=true,      -- Header attributes
    line_blocks=true,            -- Line blocks
    escaped_line_breaks=true,    -- Pandoc-style escaped hard line breaks
}
local writer = lunamark.writer.html5.new(opts)
local template = ''
local h = io.open("default.template", 'r')
if nil ~= h then
    template = h:read('*a')
    h:close()
else
    print('oops! No such file ' .. 'default.template')
end
-- Can override the various writer functions, there's something for each of the basic HTML elements.
--    Override anything that's generic.
local parse = lunamark.reader.markdown.new(writer, opts)



-- Some global data.
local globalData = {
    ['s'] = ' ', ['_'] = ' ', ['dlr'] = '$',
    ['devuanCinnabarDark']   = '#310202',    ['devuanCinnabarLight']  = '#510505',
    ['devuanDarkPurpyDark']  = '#33313b',    ['devuanDarkPurpyLight'] = '#3c3a45',
    ['devuanDeepSeaDark']    = '#132f40',    ['devuanDeepSeaLight']   = '#1a4562',
    ['devuanSaphireDark']    = '#004489',    ['devuanSaphireLight']   = '#00509f',
    ['karenPurple']          = '#8800ff',    ['onefangPurple']        = '#cc00ff',
    favicon = 'nYAW_icon.png', logo = 'nYAW.png',
    header = '', home = '', history = '',  footer = 'Powered by <a href="https://sledjhamr.org/cgit/notYetAnotherWiki/about/">notYetAnotherWiki</a> version 0.0. &nbsp;',
     --menu = '',
}
local Files, Subs = {}, {}



-- Useful functions, part 0.

-- A simple table.subtable = subtable wont work, you end up with a reference so that changes to the later get applied to the former.
local derefiTable = function(t, strip)
    local argh = {}
    for l, y in ipairs(t) do	if (l ~= y.name) and strip then table.insert(argh, y) end	end
    return argh
end
local derefTable = function(t, strip)
    local argh = {}
    for l, y in pairs(t) do	argh[l] = y end
    return argh
end


-- String together the bits array into a path string.  Or the other way around.  lol
local stringBits = function(l)
    local bits = {}
    local last = 1
    for j = 1, #l do
	if '/' == string.sub(l, j, j) then
	    table.insert(bits, string.sub(l, last, j - 1))
	    last = j + 1
	end
    end
    return bits, string.sub(l, last)
end


-- Put a value into the Files or Subs table, creating things if needed.
local toFile = function(name, key, value)
    if nil == Files[name] then
	local bits, bit = stringBits(name)
	local path = ''
	Files[name] = {}
	Files[name].bits = bits
	Files[name].bit = bit
	for i, d in ipairs(bits) do
	    if '' ~= path then path = path .. '/' end
	    path = path .. d
	end
	Files[name].path = path
--	Files[name].body = ''
    end
    if nil ~= key         then Files[name][key] = value end
    for i, v in ipairs{'metadata', 'bits', } do
	if nil == Files[name][v] then Files[name][v] = {} end
    end
end
local toSub = function(name, key, value)
    if nil == Subs[name] then Subs[name] = {} end
    if nil ~= key        then Subs[name][key] = value end
    for i, v in ipairs{'metadata', 'bits', 'files', 'subs'} do
	if nil == Subs[name][v] then Subs[name][v] = {} end
    end
end



-- Actually start doing things.

-- Create the base of everything.md here, so it gets picked up as usual in the file scan.
local body, h = '', io.open('everything.md', 'w')
h:write('# All the pages\n')
h:close()


-- Scan the subdirectories looking for .md files.
local directory = arg[1]
toSub('')
if nil == directory then directory = '.' end
if '.' ~= directory then
    for l in io.popen('find . -name "*.md" -type f,l -printf "%P\n"'):lines() do
	toFile(string.gsub(l, '%.md$', ''))
    end
end
-- Can add in a distant directory to, for putting it's results in the current directory.
for l in io.popen('find ' .. directory .. ' -name "*.md" -type f,l -printf "%P\n"'):lines() do
    local n = string.gsub(l, '%.md$', '')
    if nil == Files[n] then toFile(n) end
end


-- Gotta figure out all the files and subs first.  File and sub metadata comes along for the ride, coz we need them later.
local newMeta = {}
for name, file in pairs(Files) do
    local bitter, path = '', ''
    local bits, bit = file.bits, file.bit
    local ln = #bits
    local body, metadata = '', {}

    -- Go through our bits, construct Subs with bits.
    if ln > 0 then bitter = bits[1] end
    if '' ~= bitter then Subs[''].subs[bitter] = bitter end	-- "bitter end" was entirely by accident, I'm keeping it.  B-)
    for i, d in ipairs(bits) do
	if '' ~= path then path = path .. '/' end
	path = path .. d
	toSub(path, 'bits', derefiTable(bits, true))
	if i < ln 		then
	    Subs[path].subs[bits[i + 1]] = bits[i + 1]
	    table.remove(Subs[path].bits, #bits)
	end
    end

    if '.md' == string.sub(name, -3, -1) then
	-- This is a metadata only file, no content, stash the matadata.
	for l in io.open(name .. '.md'):lines() do
	    for k, v in string.gmatch(l, "(%w+)%s*=%s*(.+)") do 
		if nil == v then
		    print(name .. ' ' .. k)
		else
		    metadata[k] = v
		end
	    end
	end
	if '.md' == name                          then toSub(path, 'metadata', metadata)
	elseif '/.md' == string.sub(name, -4, -1) then toSub(path, 'metadata', metadata)
--	else                                           toFile(string.sub(name, 1, -4), 'metadata', metadata)
	else						newMeta[string.sub(name, 1, -4)] = metadata
	end
	Files[name] = nil
    end
end

-- FIXTHEM - Lua doesn't like modifying the thing you are pair()ing, like we want to do in the last loop.
for name, file in pairs(newMeta) do
    if nil == Files[name] then toFile(name) end
    if nil == Files[name].metadata then Files[name].metadata = {} end
    for k, v in pairs(file) do
	if nil == Files[name].metadata[k] then Files[name].metadata[k] = v end
    end
end

-- Open the files and do the iniital cleanups.
for name, file in pairs(Files) do
    if '.md' ~= string.sub(name, -3, -1) then
--	print('Parsing ' .. name .. '.md')
	h = io.open(name .. '.md', 'r')
	if nil ~= h then
	    body = h:read('*a') ; h:close()
	    local f0, f1, token
	    -- Deal with my typical double spaced sentence endings.
	    local result = ''
	    local start = 1
	    repeat
		f0, f1, token = string.find(body, '([%.%?%!] )', start)
		if fail ~= f0 then
		    result = result .. string.sub(body, start, f0)
		    if ' ' == string.sub(body, f1 + 1, f1 + 1) then
			result = result .. '$s$ '	-- '&nbsp;' gets turned into hex 0xA0 by parse().  So feed it another metadata token that gets translated to &nbsp;.
		    else
			result = result .. ' '
		    end
		    start = f1 + 1
		end
	    until fail == f0
	    result = result .. string.sub(body, start)
	    -- Do the same for fixing the \' \" \| etc mess pandoc left that sed can't fix.
	    body = result
	    result = ''
	    start = 1
	    repeat
		f0, f1, token = string.find(body, '(%\\[%"%\'%|%$])', start)
		if fail ~= f0 then
		    result = result .. string.sub(body, start, f0 - 1)
		    start = f1
		end
	    until fail == f0
	    result = result .. string.sub(body, start)
	    body = result
	end
	Files[name].body = body
	table.insert(Subs[Files[name].path].files, Files[name].bit)
    end
end

-- Create an "everything" page, for URL links to every file.HTML.
-- TODO - sort the list of pages.
local bdy, h = Files['everything'].body, io.open('everything.md', 'a+')
bdy = bdy .. '\n\n| page | converted | Foswiki | PmWiki | \n| ---- | --------- | ------- | ------ | '
for name, file in pairs(Files) do
    local metadata = derefTable(Files[name].metadata, true)
    if 'everything' ~= name then
	local ln, fw, pw = 'DUNNO', '', ''
	if 'PmWiki'  == metadata.ogWiki then pw = '[' .. metadata.ogURL .. '](' .. metadata.ogURL .. ')' end
	if 'Foswiki' == metadata.ogWiki then fw = '[' .. metadata.ogURL .. '](' .. metadata.ogURL .. ')' end
	if nil ~= file.bit   then ln = file.bit
	end
	bdy = bdy .. '\n| ' .. name .. ' | [' .. ln .. '](<' .. name .. '.HTML>) | ' .. fw .. ' | ' .. pw .. ' |'
    end
end
h:write(bdy)
h:close()
toFile('everything', 'body', parse(bdy))



-- These functions assume the above file and sub scan has completed.

-- Which page in this directory should we show?
-- NOTE - only looking for the .md files we scanned for before, any stray HTML, html, HTM, and htm files will get ignored.
local whichPage = function(f)
    local fl = ''
    if nil ~= Subs[f] then
	if nil ~= Subs[f].whichPage then return Subs[f].whichPage end
	if nil ~= Subs[f].files then
	    if 1 == #(Subs[f].files) then	fl = Subs[f].files[1] else
		-- Standard files to search for.
		for i, v in ipairs{'about', 'readme', 'index', 'homepage', 'mainpage', 'webhome'} do
		    for j, w in ipairs(Subs[f].files) do
			if v == string.lower(w) then
			    fl = w
			    break
			end
		    end
		    if '' ~= fl then break end
		end
		-- If nothing else, just grab the first one.
		if ('' == fl) and (nil ~= Subs[f].files[1]) then fl = Subs[f].files[1] end
	    end
	end
    end
    if '' ~= fl then fl = fl .. '.HTML' ; Subs[f].whichPage = fl end
    return fl
end


-- Calculate a link from the source directory to the destination directory.
local linkFrom = function(source, dest)
    local depth = 0
    local link = ''
    if source ~= dest then
	for i, v in ipairs(Subs[source].bits) do
	    if v ~= Subs[dest].bits[i] then
		depth = i
		break
	    end
	end

	if #(Subs[dest].bits) >= #(Subs[source].bits) then
	    depth = #(Subs[source].bits)
	    for i, v in ipairs(Subs[dest].bits) do
		if i > depth then
		    if '' ~= link then link = link .. '/' end
		    link = link .. Subs[dest].bits[i]
		end
	    end
	    if '' ~= link then link = link .. '/' end
	else
	    depth = #(Subs[source].bits) - depth
	    depth = depth + 1
	    link = string.rep('../', depth)
	end
    end
    return link
end



-- More of this actually doing things nonsense.

-- Loop through Subs, doing whichPage and inheritance.
for name, sub in pairs(Subs) do
    sub.whichPage = whichPage(name)
    local metadata = sub.metadata
    for i, s in pairs(sub.subs) do
	local nm = i
	if '' ~= name then nm = name .. '/' .. i end
	ss = Subs[nm]
	for k, v in pairs(metadata) do
	    if nil == ss.metadata[k] then
		if ('favicon' == k) or ('logo' == k) then
		    ss.metadata[k] = linkFrom(nm, name) .. v
		else
		    ss.metadata[k] = v
		end
	    end
	end
    end
end

-- Loop through the files we found and actually create their HTML files.
for name, file in pairs(Files) do
    local path, result = '', ''
    local body, metadata = Files[name].body, derefTable(Files[name].metadata, true)
    local bits, bit = Files[name].bits, Files[name].bit
    local ln = #bits

    path = table.concat(bits, '/', 1, ln)

    if '' ~= body then
	-- Inherit stuff from sub and global.
	local mdata = Subs[path].metadata
	for k, v in pairs(mdata) do
	    if nil == file.metadata[k] then
		file.metadata[k] = v
	    end
	end
	Files[name].metadata = file.metadata
	metadata = derefTable(Files[name].metadata, true)
	for		m, x in pairs(globalData)		do if nil == metadata[m] then metadata[m] = x end end

	if nil ~= metadata.ogURL then
	    body = body .. '\n\n---\n\n[Original page](' .. metadata.ogURL .. '), maybe you can edit it.\n'
	end

	-- Figure out this pages trail links.
	metadata.home = linkFrom(path, '') .. Subs[''].whichPage
	metadata.trail = ''
	for i, b in ipairs(bits) do
	    local p = table.concat(bits, '/', 1, i)
	    if i < #bits then
		metadata.trail = metadata.trail .. '<a href="' .. linkFrom(path, p) .. Subs[p].whichPage .. '">' .. b .. '</a> &#x1f463; &nbsp; '
		linkFrom(path, table.concat(bits, '/', 1, i))
	    else
		metadata.trail = metadata.trail ..  b .. ' &nbsp; '
	    end
	end

	-- Figure out this pages header links.
	metadata.header = ''
	subs = {}
	for i, f in pairs(Subs[path].subs) do
	    table.insert(subs, f)
	end
	table.sort(subs, function(a, b) return (string.lower(a) < string.lower(b))  end)
	for i, f in ipairs(subs) do
	    local pth = path
	    if '' ~= path then pth = path .. '/' end
	    metadata.header = metadata.header .. '<a href="' .. f .. '/' .. whichPage(pth .. f) .. '">' .. f .. '</a> &nbsp; '
	end

	-- Figure out this pages menu links.
	metadata.menu = ''
	if nil == metadata.title then metadata.title = bit end
	if nil ~= Subs[path].files then table.sort(Subs[path].files, function(a, b) return (string.lower(a) < string.lower(b))  end)  end
	for i, f in ipairs(Subs[path].files) do
	    local title, url = nil, nil
	    if '' == path then
		title = Files[f].metadata.title
		url   = Files[f].metadata.URL
	    else
		title = Files[path .. '/' .. f].metadata.title
		url   = Files[path .. '/' .. f].metadata.URL
	    end
	    if nil == title then title = f end
	    if bit == f then		metadata.menu = metadata.menu .. '<p>' .. title .. '</p>'
	    else
		if nil ~= url then	metadata.menu = metadata.menu .. '<p><a href="' .. url .. '">'      .. title .. ' &#9757;</a></p>'
		else			metadata.menu = metadata.menu .. '<p><a href="' .. f   .. '.HTML">' .. title .. '</a></p>'
		end
	    end
	end

	-- Figure out this pages footer links.
	if nil ~= metadata.pagehistory then metadata.history = '<p>Page&nbsp;<a href="' .. metadata.pagehistory .. '/' .. name .. '.md">history</a></p>' end
	if nil ~= metadata.sourcecode	then metadata.footer = '<a href="' .. metadata.sourcecode	.. '">source code</a> &nbsp; &nbsp; ' .. metadata.footer    end
	if nil ~= metadata.feedatom		then metadata.footer = '<a href="' .. metadata.feedatom		..   '">atom feed</a> &nbsp; &nbsp; ' .. metadata.footer    end
	if metadata.footer ~= globalData.footer then metadata.footer = 'Web site ' .. metadata.footer end
	metadata.footer = '<p>' .. metadata.footer .. '</p>'

	-- Do our own metadata replacement, it's simple and works better.
	local temp = template
	local start = 1
	local f0, f1, token
	-- Toss the body in first, so the scan can deal with it to.
	f0, f1, token = string.find(temp, '%$(body)%$')
	if fail ~= f0 then
	    -- NOTE - this is where we actually parse the markup into HTML.
	    temp = string.sub(temp, 1, f0 - 1) .. parse(body) .. string.sub(temp, f1 + 1)
	end
	-- The actual metadata replacement scan.
	result = ''
	repeat
	    f0, f1, token = string.find(temp, '%$([%w_]+)%$', start)
	    if fail ~= f0 then
		if nil ~= metadata[token] then result = result .. string.sub(temp, start, f0 - 1) .. metadata[token] end
		start = f1 + 1
	    end
	until fail == f0
	result = result .. string.sub(temp, start)

	-- Write the file.
	if '' ~= result then
	    local base = name .. '.HTML'
--	    print('From ' .. name .. '.md -> ' .. base)
	    local a, e = io.open(base, 'w')
	    if nil == a then print('Could not open ' .. base .. ' - ' .. e) else
		a:write(result)
		a:close()
	    end
	end
    end
end