-- Figlet font API
-- Created by MaoZedong

local function split(str)
    local parts = {}

    for part in str:gmatch("[^%s]+") do
        table.insert(parts, part)
    end

    return parts
end

local function skip(tbl, n)
    return table.pack(select(n + 1, table.unpack(tbl)))
end

local function esc(x)
    return (x:gsub('%%', '%%%%')
    :gsub('^%^', '%%^')
    :gsub('%$$', '%%$')
    :gsub('%(', '%%(')
    :gsub('%)', '%%)')
    :gsub('%.', '%%.')
    :gsub('%[', '%%[')
    :gsub('%]', '%%]')
    :gsub('%*', '%%*')
    :gsub('%+', '%%+')
    :gsub('%-', '%%-')
    :gsub('%?', '%%?'))
end

function parseFont(name)
    local f = fs.open(name, "r")
    local lines = {}

    for line in f.readLine do
        table.insert(lines, line)
    end

    f.close()

    local header = split(lines[1])
    local hardblank = header[1]:sub(#header[1], #header[1])
    local height = math.abs(tonumber(header[2]))
    local comments = math.abs(tonumber(header[6]))

    local fontLines = skip(lines, comments + 1)

    return {
        fontLines = fontLines,
        hardblank = hardblank,
        height = height,
        chars = {}
    }
end

local function parseChar(char, font)
    if font.chars[char] ~= nil then
        return font.chars[char]
    end

    local height = font.height
    local start = (string.byte(char) - 32) * height
    local charLines = {}

    for i = 1, height do
        charLines[i] = font.fontLines[start + i]
        :gsub("@", "")
        :gsub(esc(font.hardblank), " ")
    end

    font.chars[char] = charLines

    return charLines
end

function write(font, str)
    local chars = {}
    local result = ""

    for i = 1, #str do
        chars[i] = parseChar(str:sub(i, i), font)
    end

    for i = 1, #chars[1] do
        for j = 1, #str do
            result = result .. chars[j][i]
        end

        result = result .. "\n"
    end

    return result
end