--TODO: ascending sort as well?
--TODO: limit and cursor fields
function handle()
	if not params.chart then 
		error("chartNotFound")
		return
	end
	local chart = db.get(params.chart)
	if not chart then
		error("chartNotFound")
		return
	end

	local game = db.get(chart.game)
	local tableName = getTableName(chart.game)

	local componentOrder = game.componentOrder
	if not componentOrder and params.listComponents then
		componentOrder = toarray({})
		local i = 0
		for k, _ in game.scoreComponents do
			i = i+1
			componentOrder[i] = k
		end
	end

	local mode = params.mode
	if game.modes and not mode then
		mode = game.modes[1]
	end
	local inputMethod = params.inputMethod
	if game.inputMethods and not inputMethod then
		inputMethod = game.inputMethods[1]
	end
	local versions = params.versions
	if chart.rankedVersions and not versions then
		versions = chart.rankedVersions
	end
	local sortBy = params.sortBy
	if not sortBy then
		sortBy = game.defaultComponent
	end

	local query = "SELECT uri, did, MAX(" .. sortBy .. ") "
	query = query .. "FROM '" .. tableName .. "' WHERE chart = '" .. params.chart .. "' "
	if mode then
		query = query .. "AND mode = '" .. mode .. "' "
	end
	if inputMethod then
		query = query .. "AND inputMethod = '" .. inputMethod .. "' "
	end
	if versions then
		if #versions > 1 then
			query = query .. "AND ("
			for i, v in ipairs(versions) do
				query = query .. "version = '" .. v .. "' "
				if i < #versions then
					query = query .. "OR "
				end
			end
			query = query .. ") "
		else
			query = query .. "AND version = '" .. versions[1] .. "' "
		end
	end
	query = query .. "GROUP BY did ORDER BY " .. sortBy .. " DESC"

	local rows = db.raw(query)

	local leaderboard = toarray({})

	for _, row in ipairs(rows) do
		local entry = {}
		entry["did"] = row.did
		local resp = http.get("https://slingshot.microcosm.blue/xrpc/blue.microcosm.identity.resolveMiniDoc?identifier=" .. row.did)
		entry["handle"] = json.decode(resp.body).handle
		local profile = db.get("at://" .. row.did .. "/dev.tsunagite.profile/" .. tableName)
		if profile then
			entry["profile"] = profile
		end
		entry["score"] = db.get(row.uri)
		table.insert(leaderboard, entry)
	end
	local result = {["scores"] = leaderboard}
	if params.listComponents then
		result["components"] = game.scoreComponents
		result["componentOrder"] = componentOrder
	end
	return result
end

function getTableName(uri)
	local trimmed = string.sub(uri, string.len("at://")+1)
	local did = string.sub(trimmed, 1, string.find(trimmed, "/")-1)
	local _, j = string.find(trimmed, "dev.tsunagite.game/")
	local key = string.sub(trimmed, j+1, string.len(trimmed))
	local resp = http.get("https://slingshot.microcosm.blue/xrpc/blue.microcosm.identity.resolveMiniDoc?identifier=" .. did)
	local hdl = json.decode(resp.body).handle
	local splitHandle = {}
	for str in string.gmatch(hdl, "([^.]+)") do
		table.insert(splitHandle, str)
	end
	local result = ""
	for i=0, #splitHandle-1 do
		result = result .. splitHandle[#splitHandle-i] .. "."
	end
	result = result .. key
	return result
end