dotfiles/.config/lite-xl/libraries/widget/fonts/info.lua

547 lines
14 KiB
Lua

-- Based on the code from:
-- https://gist.github.com/zr-tex8r/1969061a025fa4fc5486c9c28460f48e
local Object = require "core.object"
--------------------------------------------------------------------------------
-- Class Declarations
--------------------------------------------------------------------------------
---@class widget.fonts.cdata : core.object
---@field private data string
---@field private position integer
local FontCDATA = Object:extend()
---@class widget.fonts.reader : core.object
---@field private file file*
---@field private path string
local FontReader = Object:extend()
---@class widget.fonts.data
---@field public path string
---@field public id number @Numerical id of the font
---@field public type '"ttc"' | '"ttf"' | '"otf"'
---@field public copyright string
---@field public family string
---@field public subfamily '"Regular"' | '"Bold"' | '"Italic"' | '"Bold Italic"'
---@field public fullname string
---@field public version string
---@field public psname string
---@field public url string
---@field public license string
---@field public tfamily string
---@field public tsubfamily '"Regular"' | '"Bold"' | '"Italic"' | '"Bold Italic"'
---@field public wwsfamily string
---@field public wwssubfamily string
---@field public monospace boolean
---@class widget.fonts.info : core.object
---@field private reader widget.fonts.reader
---@field public path string @Path of the font file
---@field public data widget.fonts.data[] @Holds the metadata for each of the embedded fonts
local FontInfo = Object:extend()
---@alias widget.fonts.style
---|>'"regular"'
---| '"bold"'
---| '"italic"'
---| '"bold italic"'
---| '"thin"'
---| '"medium"'
---| '"light"'
---| '"black"'
---| '"condensed"'
---| '"oblique"'
---| '"bold oblique"'
---| '"extra nold"'
---| '"Extra bold italic"'
---| '"bold condensed"'
--------------------------------------------------------------------------------
-- FontCDATA Implementation
--------------------------------------------------------------------------------
function FontCDATA:new(data)
self.data = data
self.position = 0
end
function FontCDATA:__tostring()
return "cdata(pos="..self.position..")"
end
function FontCDATA:pos(p)
if not p then return self.position end
self.position = p
return self
end
function FontCDATA:unum(b)
local v, data = 0, self.data
assert(#data >= self.position + b, 11)
for _ = 1, b do
self.position = self.position + 1
v = v * 256 + data:byte(self.position)
end
return v
end
function FontCDATA:setunum(b, v)
local t, data = {}, self.data
t[1] = data:sub(1, self.position)
self.position = self.position + b
assert(#data >= self.position, 12)
t[b + 2] = data:sub(self.position + 1)
for i = 1, b do
t[b + 2 - i] = string.char(v % 256)
v = math.floor(v / 256)
end
self.data = table.concat(t, '')
return self
end
function FontCDATA:str(b)
local data = self.data
self.position = self.position + b
assert(#data >= self.position, 13)
return data:sub(self.position - b + 1, self.position)
end
function FontCDATA:setstr(s)
local t, data = {}, self.data
t[1], t[2] = data:sub(1, self.position), s
self.position = self.position + #s
assert(#data >= self.position, 14)
t[3] = data:sub(self.position + 1)
self.data = table.concat(t, '')
return self
end
function FontCDATA:ushort()
return self:unum(2)
end
function FontCDATA:ulong()
return self:unum(4)
end
function FontCDATA:setulong(v)
return self:setunum(4, v)
end
function FontCDATA:ulongs(num)
local t = {}
for i = 1, num do
t[i] = self:unum(4)
end
return t
end
--------------------------------------------------------------------------------
-- FontReader Implementation
--------------------------------------------------------------------------------
function FontReader:new(font_path)
local file, errmsg = io.open(font_path, "rb")
assert(file, errmsg)
self.file = file
self.path = font_path
end
function FontReader:__gc()
if self.file then
self.file:close()
end
end
function FontReader:__tostring()
return "reader("..self.path..")"
end
---@param offset integer
---@param len integer
---@return widget.fonts.cdata?
---@return string|nil errmsg
function FontReader:cdata(offset, len)
local data, errmsg = self:read(offset, len)
if data then
return FontCDATA(data)
end
return nil, errmsg
end
function FontReader:read(offset, len)
self.file:seek("set", offset)
local data = self.file:read(len)
if data:len() ~= len then
return nil, "failed reading font data"
end
return data
end
function FontReader:close()
self.file:close()
self.file = nil
end
--------------------------------------------------------------------------------
-- FontInfo Helper Functions
--------------------------------------------------------------------------------
-- speeds up function lookups
local floor, ceil = math.floor, math.ceil
local function div(x, y)
return floor(x / y), x % y
end
local function utf16betoutf8(src)
local s, d = { tostring(src):byte(1, -1) }, {}
for i = 1, #s - 1, 2 do
local c = s[i] * 256 + s[i+1]
if c < 0x80 then d[#d+1] = c
elseif c < 0x800 then
local x, y = div(c, 0x40)
d[#d+1] = x + 0xC0; d[#d+1] = y + 0x80
elseif c < 0x10000 then
local x, y, z = div(c, 0x1000); y, z = div(y, 0x40)
d[#d+1] = x + 0xE0; d[#d+1] = y + 0x80; d[#d+1] = z + 0x80
else
assert(nil)
end
end
return string.char(table.unpack(d))
end
local file_type = {
[0x74746366] = 'ttc',
[0x10000] = 'ttf',
[0x4F54544F] = 'otf',
[1008813135] = 'ttc'
}
---@param reader widget.fonts.reader
local function otf_offset(reader)
local cd, errmsg = reader:cdata(0, 12)
if not cd then
return nil, errmsg
end
local tag = cd:ulong()
local ftype = file_type[tag];
if ftype == 'ttc' then
local ver = cd:ulong();
local num = cd:ulong();
cd, errmsg = reader:cdata(12, 4 * num)
if not cd then
return nil, errmsg
end
local res = cd:ulongs(num);
return res
elseif ftype == 'otf' or ftype == 'ttf' then
return { 0 }
else
return nil, string.format("unknown file tag: %s", tag)
end
end
---@param reader widget.fonts.reader
---@param fofs integer
---@param ntbl integer
local function otf_name_table(reader, fofs, ntbl)
local cd_d = reader:cdata(fofs + 12, 16 * ntbl)
if not cd_d then
return nil, "error reading names table"
end
for _ = 1, ntbl do
local t = {-- tag, csum, ofs, len
cd_d:str(4), cd_d:ulong(), cd_d:ulong(), cd_d:ulong()
}
if t[1] == 'name' then
return reader:cdata(t[3], ceil(t[4] / 4) * 4)
end
end
return nil, "name table is missing"
end
---@param cdata widget.fonts.cdata
local function otf_name_records(cdata)
local nfmt, nnum, nofs = cdata:ushort(), cdata:ushort(), cdata:ushort()
assert(nfmt == 0, string.format("unsupported name table format: %s", nfmt))
local nr = {}
for i = 1, nnum do
nr[i] = { -- pid, eid, langid, nameid, len, ofs
cdata:ushort(), cdata:ushort(), cdata:ushort(),
cdata:ushort(), cdata:ushort(), cdata:ushort() + nofs
}
end
return nr
end
---@param cdata widget.fonts.cdata
local function otf_name(cdata, nr, nameid)
local function seek(pid, eid, lid)
for i = 1, #nr do
local t = nr[i]
local ok = (t[4] == nameid and t[1] == pid and t[2] == eid and
t[3] == lid)
if ok then return t end
end
end
local rec = seek(3, 1, 0x409)
or seek(3, 10, 0x409)
or seek(1, 0, 0) or seek(0, 3, 0)
or seek(0, 4, 0) or seek(0, 6, 0)
if not rec then return '' end
local s = cdata:pos(rec[6]):str(rec[5])
return (rec[1] == 3) and utf16betoutf8(s) or s
end
---@param reader widget.fonts.reader
local function otf_list(reader, fid, fofs)
local cd_fh, errmsg = reader:cdata(fofs, 12)
if not cd_fh then
return nil, errmsg
end
local tag = cd_fh:ulong()
local ntbl = cd_fh:ushort()
local cd_n = nil
cd_n, errmsg = otf_name_table(reader, fofs, ntbl)
if not cd_n then
return nil, errmsg
end
local ext = { id = fid; type = file_type[tag] or '' }
local nr = nil
nr, errmsg = otf_name_records(cd_n)
if not nr then
return nil, errmsg
end
local output = {
id = ext.id,
type = ext.type,
copyright = otf_name(cd_n, nr, 0),
family = otf_name(cd_n, nr, 1),
subfamily = otf_name(cd_n, nr, 2),
fullname = otf_name(cd_n, nr, 4),
version = otf_name(cd_n, nr, 5),
psname = otf_name(cd_n, nr, 6),
url = otf_name(cd_n, nr, 11),
license = otf_name(cd_n, nr, 13),
tfamily = otf_name(cd_n, nr, 16),
tsubfamily = otf_name(cd_n, nr, 17),
}
return output
end
--------------------------------------------------------------------------------
-- FontInfo Implementation
--------------------------------------------------------------------------------
---Helper function to check and update a font monospace attribute.
---@param font_data widget.fonts.data
---@return boolean checked
---@return string? errmsg
function FontInfo.check_is_monospace(font_data)
if font_data then
local loaded, fontren = pcall(renderer.font.load, font_data.path, 8, {})
if not loaded then
return false, "could not load font"
else
if fontren:get_width("|") == fontren:get_width("w") then
font_data.monospace = true
else
font_data.monospace = false
end
end
end
return true
end
---Constructor
---@param font_path? string
function FontInfo:new(font_path)
if type(font_path) == "string" then
self:read(font_path)
else
self.data = {}
self.path = ""
self.last_error = "no font given"
end
end
local function fontinfo_read_native(self, font_path)
---@type widget.fonts.data
local font
---@type string?
local errmsg
---@diagnostic disable-next-line
font, errmsg = renderer.font.get_metadata(font_path)
if not font then
self.last_error = errmsg
return font, errmsg
end
local add = true
local family = nil
if font.tfamily then
family = font.tfamily
elseif font.family then
family = font.family
end
local subfamily = nil
if font.tsubfamily then
subfamily = font.tsubfamily -- sometimes tsubfamily includes more styles
elseif font.subfamily then
subfamily = font.subfamily
end
-- fix font meta data or discard if empty
if family and subfamily then
font.fullname = family .. " " .. subfamily
elseif font.fullname and family and not font.fullname:ufind(family, 1, true) then
font.fullname = font.fullname .. " " .. family
elseif not font.fullname and family then
font.fullname = family
else
self.last_error = "font metadata is empty"
add = false
end
if add then
table.insert(self.data, font)
else
return nil, self.last_error
end
return true
end
local function fontinfo_read_nonnative(self, font_path)
self.reader = FontReader(font_path)
local tofs, errmsg = otf_offset(self.reader)
if not tofs then
self.last_error = errmsg
return nil, errmsg
end
local data = nil
for i = 1, #tofs do
data, errmsg = otf_list(self.reader, i - 1, tofs[i])
if data then
table.insert(self.data, data)
else
self.last_error = errmsg
return nil, errmsg
end
end
if self.data[1] then
local font = self.data[1]
local family = nil
if font.tfamily ~= "" then
family = font.tfamily
elseif font.family ~= "" then
family = font.family
end
local subfamily = nil
if font.tsubfamily ~= "" then
subfamily = font.tsubfamily -- sometimes tsubfamily includes more styles
elseif font.subfamily ~= "" then
subfamily = font.subfamily
end
-- fix font meta data or discard if empty
if family and subfamily then
font.fullname = family .. " " .. subfamily
elseif font.fullname ~= "" and family and not font.fullname:ufind(family, 1, true) then
font.fullname = font.fullname .. " " .. family
elseif font.fullname == "" and family then
font.fullname = family
else
self.data = {}
self.last_error = "font metadata is empty"
return nil, self.last_error
end
end
self.reader:close()
return true
end
---Open a font file and read its metadata.
---@param font_path string
---@return widget.fonts.info?
---@return string|nil errmsg
function FontInfo:read(font_path)
self.data = {}
self.path = font_path
local read, errmsg
---@diagnostic disable-next-line
if type(renderer.font.get_metadata) == "function" then
read, errmsg = fontinfo_read_native(self, font_path)
else
read, errmsg = fontinfo_read_nonnative(self, font_path)
end
if not read then
return read, errmsg
end
return self
end
---Get the amount of collections on the font file.
---@return integer
function FontInfo:embedded_fonts_count()
return #self.data
end
---Get the metadata of a previously read font file without
---copyright and license information which can be long.
---@param idx? integer Optional position of the embedded font
---@return widget.fonts.data?
---@return string|nil errmsg
function FontInfo:get_data(idx)
idx = idx or 1
local data = {}
if #self.data > 0 and self.data[idx] then
data = self.data[idx]
else
return nil, self.last_error
end
return {
path = self.path,
id = data.id,
type = data.type,
family = data.family,
subfamily = data.subfamily,
fullname = data.fullname,
version = data.version,
psname = data.psname,
url = data.url,
tfamily = data.tfamily,
tsubfamily = data.tsubfamily,
wwsfamily = data.wwsfamily,
wwssubfamily = data.wwssubfamily,
monospace = data.monospace or false
}
end
return FontInfo