--
-- Simple JSON encoding and decoding in pure Lua.
--
-- Copyright 2010-2016 Jeffrey Friedl
-- http://regex.info/blog/
-- Latest version: http://regex.info/blog/lua/json
--
-- This code is released under a Creative Commons CC-BY "Attribution" License:
-- http://creativecommons.org/licenses/by/3.0/deed.en_US
--
-- It can be used for any purpose so long as:
--    1) the copyright notice above is maintained
--    2) the web-page links above are maintained
--    3) the 'AUTHOR_NOTE' string below is maintained
--
local AUTHOR_NOTE = "-[ JSON.lua package by Jeffrey Friedl (http://regex.info/blog/lua/json) version 20161109.21 ]-"

local _, GL = ...;

GL.JSON = {};

local JSON = GL.JSON;

local default_pretty_indent  = "  "
local default_pretty_options = { pretty = true, align_keys = false, indent = default_pretty_indent, }

local isArray  = { __tostring = function() return "JSON array"         end }  isArray.__index  = isArray
local isObject = { __tostring = function() return "JSON object"        end }  isObject.__index = isObject

function JSON:newArray(tbl)
    return setmetatable(tbl or {}, isArray)
end

function JSON:newObject(tbl)
    return setmetatable(tbl or {}, isObject)
end

local function getnum(op)
    return type(op) == 'number' and op or op.N
end

local isNumber = {
    __tostring = function(T)  return T.S        end,
    __unm      = function(op) return getnum(op) end,

    __concat   = function(op1, op2) return tostring(op1) .. tostring(op2) end,
    __add      = function(op1, op2) return getnum(op1)   +   getnum(op2)  end,
    __sub      = function(op1, op2) return getnum(op1)   -   getnum(op2)  end,
    __mul      = function(op1, op2) return getnum(op1)   *   getnum(op2)  end,
    __div      = function(op1, op2) return getnum(op1)   /   getnum(op2)  end,
    __mod      = function(op1, op2) return getnum(op1)   %   getnum(op2)  end,
    __pow      = function(op1, op2) return getnum(op1)   ^   getnum(op2)  end,
    __lt       = function(op1, op2) return getnum(op1)   <   getnum(op2)  end,
    __eq       = function(op1, op2) return getnum(op1)   ==  getnum(op2)  end,
    __le       = function(op1, op2) return getnum(op1)   <=  getnum(op2)  end,
}
isNumber.__index = isNumber

function JSON:asNumber(item)

    if getmetatable(item) == isNumber then
        -- it's already a JSON number object.
        return item
    elseif type(item) == 'table' and type(item.S) == 'string' and type(item.N) == 'number' then
        -- it's a number-object table that lost its metatable, so give it one
        return setmetatable(item, isNumber)
    else
        -- the normal situation... given a number or a string representation of a number....
        local holder = {
            S = tostring(item), -- S is the representation of the number as a string, which remains precise
            N = tonumber(item), -- N is the number as a Lua number.
        }
        return setmetatable(holder, isNumber)
    end
end

--
-- Given an item that might be a normal string or number, or might be an 'isNumber' object defined above,
-- return the string version. This shouldn't be needed often because the 'isNumber' object should autoconvert
-- to a string in most cases, but it's here to allow it to be forced when needed.
--
function JSON:forceString(item)
    if type(item) == 'table' and type(item.S) == 'string' then
        return item.S
    else
        return tostring(item)
    end
end

--
-- Given an item that might be a normal string or number, or might be an 'isNumber' object defined above,
-- return the numeric version.
--
function JSON:forceNumber(item)
    if type(item) == 'table' and type(item.N) == 'number' then
        return item.N
    else
        return tonumber(item)
    end
end

local function unicode_codepoint_as_utf8(codepoint)
    --
    -- codepoint is a number
    --
    if codepoint <= 127 then
        return strchar(codepoint)

    elseif codepoint <= 2047 then
        --
        -- 110yyyxx 10xxxxxx         <-- useful notation from http://en.wikipedia.org/wiki/Utf8
        --
        local highpart = math.floor(codepoint / 0x40)
        local lowpart  = codepoint - (0x40 * highpart)
        return strchar(0xC0 + highpart,
            0x80 + lowpart)

    elseif codepoint <= 65535 then
        --
        -- 1110yyyy 10yyyyxx 10xxxxxx
        --
        local highpart  = math.floor(codepoint / 0x1000)
        local remainder = codepoint - 0x1000 * highpart
        local midpart   = math.floor(remainder / 0x40)
        local lowpart   = remainder - 0x40 * midpart

        highpart = 0xE0 + highpart
        midpart  = 0x80 + midpart
        lowpart  = 0x80 + lowpart

        --
        -- Check for an invalid character (thanks Andy R. at Adobe).
        -- See table 3.7, page 93, in http://www.unicode.org/versions/Unicode5.2.0/ch03.pdf#G28070
        --
        if ( highpart == 0xE0 and midpart < 0xA0 ) or
                ( highpart == 0xED and midpart > 0x9F ) or
                ( highpart == 0xF0 and midpart < 0x90 ) or
                ( highpart == 0xF4 and midpart > 0x8F )
        then
            return "?"
        else
            return strchar(highpart,
                midpart,
                lowpart)
        end

    else
        --
        -- 11110zzz 10zzyyyy 10yyyyxx 10xxxxxx
        --
        local highpart  = math.floor(codepoint / 0x40000)
        local remainder = codepoint - 0x40000 * highpart
        local midA      = math.floor(remainder / 0x1000)
        remainder       = remainder - 0x1000 * midA
        local midB      = math.floor(remainder / 0x40)
        local lowpart   = remainder - 0x40 * midB

        return strchar(0xF0 + highpart,
            0x80 + midA,
            0x80 + midB,
            0x80 + lowpart)
    end
end

function JSON:onDecodeError(message, text, location, etc)
    if text then
        if location then
            message = ("%s at byte %d of: %s"):format(message, location, text)
        else
            message = ("%s: %s"):format(message, text)
        end
    end

    if etc ~= nil then
        message = message .. " (" .. JSON:encode(etc) .. ")"
    end

    if self.assert then
        self.assert(false, message)
    else
        assert(false, message)
    end
end

function JSON:onTrailingGarbage(json_text, location, parsed_value, etc)
    return self:onDecodeError("trailing garbage", json_text, location, etc)
end

JSON.onDecodeOfNilError  = JSON.onDecodeError
JSON.onDecodeOfHTMLError = JSON.onDecodeError

function JSON:onEncodeError(message, etc)
    if etc ~= nil then
        message = message .. " (" .. JSON:encode(etc) .. ")"
    end

    if self.assert then
        self.assert(false, message)
    else
        assert(false, message)
    end
end

local function grok_number(self, text, start, options)
    --
    -- Grab the integer part
    --
    local integer_part = text:match('^-?[1-9]%d*', start)
            or text:match("^-?0",        start)

    if not integer_part then
        self:onDecodeError("expected number", text, start, options.etc)
        return nil, start -- in case the error method doesn't abort, return something sensible
    end

    local i = start + integer_part:len()

    --
    -- Grab an optional decimal part
    --
    local decimal_part = text:match('^%.%d+', i) or ""

    i = i + decimal_part:len()

    --
    -- Grab an optional exponential part
    --
    local exponent_part = text:match('^[eE][-+]?%d+', i) or ""

    i = i + exponent_part:len()

    local full_number_text = integer_part .. decimal_part .. exponent_part

    if options.decodeNumbersAsObjects then
        return JSON:asNumber(full_number_text), i
    end

    --
    -- If we're told to stringify under certain conditions, so do.
    -- We punt a bit when there's an exponent by just stringifying no matter what.
    -- I suppose we should really look to see whether the exponent is actually big enough one
    -- way or the other to trip stringification, but I'll be lazy about it until someone asks.
    --
    if (options.decodeIntegerStringificationLength
            and
            (integer_part:len() >= options.decodeIntegerStringificationLength or exponent_part:len() > 0))

            or

            (options.decodeDecimalStringificationLength
                    and
                    (decimal_part:len() >= options.decodeDecimalStringificationLength or exponent_part:len() > 0))
    then
        return full_number_text, i -- this returns the exact string representation seen in the original JSON
    end

    local as_number = tonumber(full_number_text)

    if not as_number then
        self:onDecodeError("bad number", text, start, options.etc)
        return nil, start -- in case the error method doesn't abort, return something sensible
    end

    return as_number, i
end


local function grok_string(self, text, start, options)

    if text:sub(start,start) ~= '"' then
        self:onDecodeError("expected string's opening quote", text, start, options.etc)
        return nil, start -- in case the error method doesn't abort, return something sensible
    end

    local i = start + 1 -- +1 to bypass the initial quote
    local text_len = text:len()
    local VALUE = ""
    while i <= text_len do
        local c = text:sub(i,i)
        if c == '"' then
            return VALUE, i + 1
        end
        if c ~= '\\' then
            VALUE = VALUE .. c
            i = i + 1
        elseif text:match('^\\b', i) then
            VALUE = VALUE .. "\b"
            i = i + 2
        elseif text:match('^\\f', i) then
            VALUE = VALUE .. "\f"
            i = i + 2
        elseif text:match('^\\n', i) then
            VALUE = VALUE .. "\n"
            i = i + 2
        elseif text:match('^\\r', i) then
            VALUE = VALUE .. "\r"
            i = i + 2
        elseif text:match('^\\t', i) then
            VALUE = VALUE .. "\t"
            i = i + 2
        else
            local hex = text:match('^\\u([0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF])', i)
            if hex then
                i = i + 6 -- bypass what we just read

                -- We have a Unicode codepoint. It could be standalone, or if in the proper range and
                -- followed by another in a specific range, it'll be a two-code surrogate pair.
                local codepoint = tonumber(hex, 16)
                if codepoint >= 0xD800 and codepoint <= 0xDBFF then
                    -- it's a hi surrogate... see whether we have a following low
                    local lo_surrogate = text:match('^\\u([dD][cdefCDEF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF])', i)
                    if lo_surrogate then
                        i = i + 6 -- bypass the low surrogate we just read
                        codepoint = 0x2400 + (codepoint - 0xD800) * 0x400 + tonumber(lo_surrogate, 16)
                    else
                        -- not a proper low, so we'll just leave the first codepoint as is and spit it out.
                    end
                end
                VALUE = VALUE .. unicode_codepoint_as_utf8(codepoint)

            else

                -- just pass through what's escaped
                VALUE = VALUE .. text:match('^\\(.)', i)
                i = i + 2
            end
        end
    end

    self:onDecodeError("unclosed string", text, start, options.etc)
    return nil, start -- in case the error method doesn't abort, return something sensible
end

local function skip_whitespace(text, start)

    local _, match_end = text:find("^[ \n\r\t]+", start) -- [http://www.ietf.org/rfc/rfc4627.txt] Section 2
    if match_end then
        return match_end + 1
    else
        return start
    end
end

local grok_one -- assigned later

local function grok_object(self, text, start, options)

    if text:sub(start,start) ~= '{' then
        self:onDecodeError("expected '{'", text, start, options.etc)
        return nil, start -- in case the error method doesn't abort, return something sensible
    end

    local i = skip_whitespace(text, start + 1) -- +1 to skip the '{'

    local VALUE = self.strictTypes and self:newObject { } or { }

    if text:sub(i,i) == '}' then
        return VALUE, i + 1
    end
    local text_len = text:len()
    while i <= text_len do
        local key, new_i = grok_string(self, text, i, options)

        i = skip_whitespace(text, new_i)

        if text:sub(i, i) ~= ':' then
            self:onDecodeError("expected colon", text, i, options.etc)
            return nil, i -- in case the error method doesn't abort, return something sensible
        end

        i = skip_whitespace(text, i + 1)

        local new_val, new_i = grok_one(self, text, i, options)

        VALUE[key] = new_val

        --
        -- Expect now either '}' to end things, or a ',' to allow us to continue.
        --
        i = skip_whitespace(text, new_i)

        local c = text:sub(i,i)

        if c == '}' then
            return VALUE, i + 1
        end

        if text:sub(i, i) ~= ',' then
            self:onDecodeError("expected comma or '}'", text, i, options.etc)
            return nil, i -- in case the error method doesn't abort, return something sensible
        end

        i = skip_whitespace(text, i + 1)
    end

    self:onDecodeError("unclosed '{'", text, start, options.etc)
    return nil, start -- in case the error method doesn't abort, return something sensible
end

local function grok_array(self, text, start, options)
    if text:sub(start,start) ~= '[' then
        self:onDecodeError("expected '['", text, start, options.etc)
        return nil, start -- in case the error method doesn't abort, return something sensible
    end

    local i = skip_whitespace(text, start + 1) -- +1 to skip the '['
    local VALUE = self.strictTypes and self:newArray { } or { }
    if text:sub(i,i) == ']' then
        return VALUE, i + 1
    end

    local VALUE_INDEX = 1

    local text_len = text:len()
    while i <= text_len do
        local val, new_i = grok_one(self, text, i, options)

        -- can't table.insert(VALUE, val) here because it's a no-op if val is nil
        VALUE[VALUE_INDEX] = val
        VALUE_INDEX = VALUE_INDEX + 1

        i = skip_whitespace(text, new_i)

        --
        -- Expect now either ']' to end things, or a ',' to allow us to continue.
        --
        local c = text:sub(i,i)
        if c == ']' then
            return VALUE, i + 1
        end
        if text:sub(i, i) ~= ',' then
            self:onDecodeError("expected comma or ']'", text, i, options.etc)
            return nil, i -- in case the error method doesn't abort, return something sensible
        end
        i = skip_whitespace(text, i + 1)
    end
    self:onDecodeError("unclosed '['", text, start, options.etc)
    return nil, i -- in case the error method doesn't abort, return something sensible
end

grok_one = function(self, text, start, options)
    -- Skip any whitespace
    start = skip_whitespace(text, start)

    if start > text:len() then
        self:onDecodeError("unexpected end of string", text, nil, options.etc)
        return nil, start -- in case the error method doesn't abort, return something sensible
    end

    if text:find('^"', start) then
        return grok_string(self, text, start, options.etc)

    elseif text:find('^[-0123456789 ]', start) then
        return grok_number(self, text, start, options)

    elseif text:find('^%{', start) then
        return grok_object(self, text, start, options)

    elseif text:find('^%[', start) then
        return grok_array(self, text, start, options)

    elseif text:find('^true', start) then
        return true, start + 4

    elseif text:find('^false', start) then
        return false, start + 5

    elseif text:find('^null', start) then
        return nil, start + 4

    else
        self:onDecodeError("can't parse JSON", text, start, options.etc)
        return nil, 1 -- in case the error method doesn't abort, return something sensible
    end
end

function JSON:decode(text, etc, options)
    --
    -- If the user didn't pass in a table of decode options, make an empty one.
    --
    if type(options) ~= 'table' then
        options = {}
    end

    --
    -- If they passed in an 'etc' argument, stuff it into the options.
    -- (If not, any 'etc' field in the options they passed in remains to be used)
    --
    if etc ~= nil then
        options.etc = etc
    end

    if type(self) ~= 'table' or self.__index ~= JSON then
        local error_message = "JSON:decode must be called in method format"
        JSON:onDecodeError(error_message, nil, nil, options.etc)
        return nil, error_message -- in case the error method doesn't abort, return something sensible
    end

    if text == nil then
        local error_message = "nil passed to JSON:decode()"
        self:onDecodeOfNilError(error_message, nil, nil, options.etc)
        return nil, error_message -- in case the error method doesn't abort, return something sensible

    elseif type(text) ~= 'string' then
        local error_message = "expected string argument to JSON:decode()"
        self:onDecodeError(("%s, got %s"):format(error_message, type(text)), nil, nil, options.etc)
        return nil, error_message -- in case the error method doesn't abort, return something sensible
    end

    if text:match('^%s*$') then
        -- an empty string is nothing, but not an error
        return nil
    end

    if text:match('^%s*<') then
        -- Can't be JSON... we'll assume it's HTML
        local error_message = "HTML passed to JSON:decode()"
        self:onDecodeOfHTMLError(error_message, text, nil, options.etc)
        return nil, error_message -- in case the error method doesn't abort, return something sensible
    end

    --
    -- Ensure that it's not UTF-32 or UTF-16.
    -- Those are perfectly valid encodings for JSON (as per RFC 4627 section 3),
    -- but this package can't handle them.
    --
    if text:sub(1,1):byte() == 0 or (text:len() >= 2 and text:sub(2,2):byte() == 0) then
        local error_message = "JSON package groks only UTF-8, sorry"
        self:onDecodeError(error_message, text, nil, options.etc)
        return nil, error_message -- in case the error method doesn't abort, return something sensible
    end

    --
    -- apply global options
    --
    if options.decodeNumbersAsObjects == nil then
        options.decodeNumbersAsObjects = self.decodeNumbersAsObjects
    end
    if options.decodeIntegerStringificationLength == nil then
        options.decodeIntegerStringificationLength = self.decodeIntegerStringificationLength
    end
    if options.decodeDecimalStringificationLength == nil then
        options.decodeDecimalStringificationLength = self.decodeDecimalStringificationLength
    end

    --
    -- Finally, go parse it
    --
    local success, value, next_i = pcall(grok_one, self, text, 1, options)

    if success then

        local error_message = nil
        if next_i ~= #text + 1 then
            -- something's left over after we parsed the first thing.... whitespace is allowed.
            next_i = skip_whitespace(text, next_i)

            -- if we have something left over now, it's trailing garbage
            if next_i ~= #text + 1 then
                value, error_message = self:onTrailingGarbage(text, next_i, value, options.etc)
            end
        end
        return value, error_message

    else

        -- If JSON:onDecodeError() didn't abort out of the pcall, we'll have received
        -- the error message here as "value", so pass it along as an assert.
        local error_message = value
        if self.assert then
            self.assert(false, error_message)
        else
            assert(false, error_message)
        end
        -- ...and if we're still here (because the assert didn't throw an error),
        -- return a nil and throw the error message on as a second arg
        return nil, error_message

    end
end

local function backslash_replacement_function(c)
    if c == "\n" then
        return "\\n"
    elseif c == "\r" then
        return "\\r"
    elseif c == "\t" then
        return "\\t"
    elseif c == "\b" then
        return "\\b"
    elseif c == "\f" then
        return "\\f"
    elseif c == '"' then
        return '\\"'
    elseif c == '\\' then
        return '\\\\'
    else
        return ("\\u%04x"):format(c:byte())
    end
end

local chars_to_be_escaped_in_JSON_string
= '['
        ..    '"'    -- class sub-pattern to match a double quote
        ..    '%\\'  -- class sub-pattern to match a backslash
        ..    '%z'   -- class sub-pattern to match a null
        ..    '\001' .. '-' .. '\031' -- class sub-pattern to match control characters
        .. ']'

local LINE_SEPARATOR_as_utf8      = unicode_codepoint_as_utf8(0x2028)
local PARAGRAPH_SEPARATOR_as_utf8 = unicode_codepoint_as_utf8(0x2029)
local function json_string_literal(value, options)
    local newval = value:gsub(chars_to_be_escaped_in_JSON_string, backslash_replacement_function)
    if options.stringsAreUtf8 then
        --
        -- This feels really ugly to just look into a string for the sequence of bytes that we know to be a particular utf8 character,
        -- but utf8 was designed purposefully to make this kind of thing possible. Still, feels dirty.
        -- I'd rather decode the byte stream into a character stream, but it's not technically needed so
        -- not technically worth it.
        --
        newval = newval:gsub(LINE_SEPARATOR_as_utf8, '\\u2028'):gsub(PARAGRAPH_SEPARATOR_as_utf8,'\\u2029')
    end
    return '"' .. newval .. '"'
end

local function object_or_array(self, T, etc)
    --
    -- We need to inspect all the keys... if there are any strings, we'll convert to a JSON
    -- object. If there are only numbers, it's a JSON array.
    --
    -- If we'll be converting to a JSON object, we'll want to sort the keys so that the
    -- end result is deterministic.
    --
    local string_keys = { }
    local number_keys = { }
    local number_keys_must_be_strings = false
    local maximum_number_key

    for key in pairs(T) do
        if type(key) == 'string' then
            table.insert(string_keys, key)
        elseif type(key) == 'number' then
            table.insert(number_keys, key)
            if key <= 0 or key >= math.huge then
                number_keys_must_be_strings = true
            elseif not maximum_number_key or key > maximum_number_key then
                maximum_number_key = key
            end
        else
            self:onEncodeError("can't encode table with a key of type " .. type(key), etc)
        end
    end

    if #string_keys == 0 and not number_keys_must_be_strings then
        --
        -- An empty table, or a numeric-only array
        --
        if #number_keys > 0 then
            return nil, maximum_number_key -- an array
        elseif tostring(T) == "JSON array" then
            return nil
        elseif tostring(T) == "JSON object" then
            return { }
        else
            -- have to guess, so we'll pick array, since empty arrays are likely more common than empty objects
            return nil
        end
    end

    table.sort(string_keys)

    local map
    if #number_keys > 0 then
        --
        -- If we're here then we have either mixed string/number keys, or numbers inappropriate for a JSON array
        -- It's not ideal, but we'll turn the numbers into strings so that we can at least create a JSON object.
        --

        if self.noKeyConversion then
            self:onEncodeError("a table with both numeric and string keys could be an object or array; aborting", etc)
        end

        --
        -- Have to make a shallow copy of the source table so we can remap the numeric keys to be strings
        --
        map = { }
        for key, val in pairs(T) do
            map[key] = val
        end

        table.sort(number_keys)

        --
        -- Throw numeric keys in there as strings
        --
        for _, number_key in ipairs(number_keys) do
            local string_key = tostring(number_key)
            if map[string_key] == nil then
                table.insert(string_keys , string_key)
                map[string_key] = T[number_key]
            else
                self:onEncodeError("conflict converting table with mixed-type keys into a JSON object: key " .. number_key .. " exists both as a string and a number.", etc)
            end
        end
    end

    return string_keys, nil, map
end

--
-- Encode
--
-- 'options' is nil, or a table with possible keys:
--
--    pretty         -- If true, return a pretty-printed version.
--
--    indent         -- A string (usually of spaces) used to indent each nested level.
--
--    align_keys     -- If true, align all the keys when formatting a table.
--
--    null           -- If this exists with a string value, table elements with this value are output as JSON null.
--
--    stringsAreUtf8 -- If true, consider Lua strings not as a sequence of bytes, but as a sequence of UTF-8 characters.
--                      (Currently, the only practical effect of setting this option is that Unicode LINE and PARAGRAPH
--                       separators, if found in a string, are encoded with a JSON escape instead of as raw UTF-8.
--                       The JSON is valid either way, but encoding this way, apparently, allows the resulting JSON
--                       to also be valid Java.)
--
--
local encode_value -- must predeclare because it calls itself
function encode_value(self, value, parents, etc, options, indent, for_key)

    --
    -- keys in a JSON object can never be null, so we don't even consider options.null when converting a key value
    --
    if value == nil or (not for_key and options and options.null and value == options.null) then
        return 'null'

    elseif type(value) == 'string' then
        return json_string_literal(value, options)

    elseif type(value) == 'number' then
        if value ~= value then
            --
            -- NaN (Not a Number).
            -- JSON has no NaN, so we have to fudge the best we can. This should really be a package option.
            --
            return "null"
        elseif value >= math.huge then
            --
            -- Positive infinity. JSON has no INF, so we have to fudge the best we can. This should
            -- really be a package option. Note: at least with some implementations, positive infinity
            -- is both ">= math.huge" and "<= -math.huge", which makes no sense but that's how it is.
            -- Negative infinity is properly "<= -math.huge". So, we must be sure to check the ">="
            -- case first.
            --
            return "1e+9999"
        elseif value <= -math.huge then
            --
            -- Negative infinity.
            -- JSON has no INF, so we have to fudge the best we can. This should really be a package option.
            --
            return "-1e+9999"
        else
            return tostring(value)
        end

    elseif type(value) == 'boolean' then
        return tostring(value)

    elseif type(value) ~= 'table' then
        self:onEncodeError("can't convert " .. type(value) .. " to JSON", etc)

    elseif getmetatable(value) == isNumber then
        return tostring(value)
    else
        --
        -- A table to be converted to either a JSON object or array.
        --
        local T = value

        if type(options) ~= 'table' then
            options = {}
        end
        if type(indent) ~= 'string' then
            indent = ""
        end

        if parents[T] then
            self:onEncodeError("table " .. tostring(T) .. " is a child of itself", etc)
        else
            parents[T] = true
        end

        local result_value

        local object_keys, maximum_number_key, map = object_or_array(self, T, etc)
        if maximum_number_key then
            --
            -- An array...
            --
            local ITEMS = { }
            local key_indent = indent .. tostring(options.indent or "")
            for i = 1, maximum_number_key do
                if not options.array_newline then
                    table.insert(ITEMS, encode_value(self, T[i], parents, etc, options, indent))
                else
                    table.insert(ITEMS, encode_value(self, T[i], parents, etc, options, key_indent))
                end
            end

            if options.pretty then
                if not options.array_newline then
                    result_value = "[ " .. table.concat(ITEMS, ", ") .. " ]"
                else
                    result_value =  "[\n"  ..  key_indent .. table.concat(ITEMS, ",\n" .. key_indent) .. "\n" ..  indent .. "]"
                end
            else
                result_value = "["  .. table.concat(ITEMS, ",")  .. "]"
            end

        elseif object_keys then
            --
            -- An object
            --
            local TT = map or T

            if options.pretty then

                local KEYS = { }
                local max_key_length = 0
                for _, key in ipairs(object_keys) do
                    local encoded = encode_value(self, tostring(key), parents, etc, options, indent, true)
                    if options.align_keys then
                        max_key_length = math.max(max_key_length, #encoded)
                    end
                    table.insert(KEYS, encoded)
                end
                local key_indent = indent .. tostring(options.indent or "")
                local subtable_indent = key_indent .. strrep(" ", max_key_length) .. (options.align_keys and "  " or "")
                local FORMAT = "%s%" .. ("%d"):format(max_key_length) .. "s: %s"

                local COMBINED_PARTS = { }
                for i, key in ipairs(object_keys) do
                    local encoded_val = encode_value(self, TT[key], parents, etc, options, subtable_indent)
                    table.insert(COMBINED_PARTS, (FORMAT):format(key_indent, KEYS[i], encoded_val))
                end
                result_value = "{\n" .. table.concat(COMBINED_PARTS, ",\n") .. "\n" .. indent .. "}"

            else

                local PARTS = { }
                for _, key in ipairs(object_keys) do
                    local encoded_val = encode_value(self, TT[key],       parents, etc, options, indent)
                    local encoded_key = encode_value(self, tostring(key), parents, etc, options, indent, true)
                    table.insert(PARTS, ("%s:%s"):format(encoded_key, encoded_val))
                end
                result_value = "{" .. table.concat(PARTS, ",") .. "}"

            end
        else
            --
            -- An empty array/object... we'll treat it as an array, though it should really be an option
            --
            result_value = "[]"
        end

        parents[T] = false
        return result_value
    end
end

local function top_level_encode(self, value, etc, options)
    local val = encode_value(self, value, {}, etc, options)
    if val == nil then
        --PRIVATE("may need to revert to the previous public verison if I can't figure out what the guy wanted")
        return val
    else
        return val
    end
end

function JSON:encode(value, etc, options)
    if type(self) ~= 'table' or self.__index ~= JSON then
        JSON:onEncodeError("JSON:encode must be called in method format", etc)
    end

    --
    -- If the user didn't pass in a table of decode options, make an empty one.
    --
    if type(options) ~= 'table' then
        options = {}
    end

    return top_level_encode(self, value, etc, options)
end

function JSON:encode_pretty(value, etc, options)
    if type(self) ~= 'table' or self.__index ~= JSON then
        JSON:onEncodeError("JSON:encode_pretty must be called in method format", etc)
    end

    --
    -- If the user didn't pass in a table of decode options, use the default pretty ones
    --
    if type(options) ~= 'table' then
        options = default_pretty_options
    end

    return top_level_encode(self, value, etc, options)
end

function JSON.__tostring()
    return "JSON encode/decode package"
end

JSON.__index = JSON

function JSON:new(args)
    local new = { }

    if args then
        for key, val in pairs(args) do
            new[key] = val
        end
    end

    return setmetatable(new, JSON)
end
