-- indiedev.games game events and leaderboards for Defold.
--
-- Put this file in your project (for example as indiedev.lua), then use it from any script:
--
--     local indiedev = require("indiedev")
--     indiedev.event("level_complete")
--     indiedev.event("level_time", 83.5) -- an optional number, such as a score or a time in seconds
--
-- Leaderboards (beta). Set the board up first on your Game Analytics page, then:
--
--     indiedev.submit_score("high_scores", "AVA", 1200, function(result) end)
--     indiedev.load_leaderboard("high_scores", function(result) end, 10)
--     -- result.ok, result.rank (after a submit), result.entries = { { rank = 1, name = "AVA", score = 1200 } }
--
-- Answers arrive later, so call indiedev.update() from the update() function of any script that runs all the time:
--
--     function update(self, dt)
--         indiedev.update()
--     end
--
-- It talks to the indiedev.games page the game runs in, and does nothing outside an HTML5 build.
-- Only the name and the number are sent. See https://indiedev.games/help/game-events-godot-defold
-- and https://indiedev.games/help/game-leaderboards

local M = {}

local pending = {}
local next_id = 1
local installed = false

function M.event(name, value)
	if not html5 then
		return
	end

	local message = { indiedev = 1, type = "event", name = name }
	if type(value) == "number" and value == value and value ~= math.huge and value ~= -math.huge then
		message.value = value
	end

	html5.run("window.parent.postMessage(" .. json.encode(message) .. ", '*')")
end

local function install()
	if installed then
		return
	end
	installed = true
	html5.run("if (!window.indiedevResults) { window.indiedevResults = {}; window.addEventListener('message', function (e) { var d = e.data; if (d && d.indiedev === 1 && d.type === 'scores') { window.indiedevResults[d.id] = JSON.stringify(d); } }); }")
end

local function ask(message, callback)
	if not html5 then
		if callback then
			callback({ ok = false, error = "not_html5", entries = {} })
		end
		return
	end

	install()
	message.indiedev = 1
	message.id = next_id
	pending[next_id] = callback or function() end
	next_id = next_id + 1
	html5.run("window.parent.postMessage(" .. json.encode(message) .. ", '*')")
end

-- The player's name is shown to everyone: 1 to 12 letters, digits, spaces, dashes or underscores. Never use a real name.
function M.submit_score(board, player_name, score, callback)
	ask({ type = "score", board = board, name = player_name, score = score }, callback)
end

function M.load_leaderboard(board, callback, limit)
	ask({ type = "leaderboard", board = board, limit = limit or 10 }, callback)
end

-- Hands the answers that arrived to their callbacks. Call it from a script's update().
function M.update()
	if not html5 or next(pending) == nil then
		return
	end

	for id, callback in pairs(pending) do
		local text = html5.run("(function () { var r = window.indiedevResults['" .. id .. "']; if (r === undefined) { return ''; } delete window.indiedevResults['" .. id .. "']; return r; })()")
		if text and text ~= "" then
			pending[id] = nil
			callback(json.decode(text))
		end
	end
end

return M