-- generating uniform random numbers before using them
math.randomseed(os.time())
math.random(); math.random(); math.random()

dRoll = 0

function onload(save_state)

    if save_state != '' then
        local sav = JSON.decode(save_state)
        self.setDescription(sav.desc)
    end

    self.createButton({click_function = 'roll_button',
        label = 'Roll',
        function_owner = self,
        position = {0, 0, 0},
        rotation = {0, 0, 0},
        width = 1000,
        height = 1000,
        font_size = 125})
end

function roll_for_damage(dice, lower, upper, base, is_targeted, player)
    dN = tonumber(dice)
    bN = tonumber(base)
    total_hits = 0
    result_sum = 0
    dmg_rolls = {}
    message = ""
    player = Player[player].steam_name
    printToAll(string.rep("=", 30) .. "\n")
    printToAll(player .. " base is " .. bN .. ", using " .. self.getName())

    -- if a single shot is made check if shot is targeted
    if dN == 1 then
        if is_targeted then
            printToAll("targeted")
        else
            total_hits = roll_to_hit(player, bN)
        end
    else
        for i = 1, dN, 1 do
            total_hits = total_hits + roll_to_hit(player, bN)
        end
    end

    -- sum all successful hits and calculate damage
    for j = 1, total_hits, 1 do
        n = math.random(lower, upper)
        table.insert(dmg_rolls, n)
        result_sum = result_sum + n
    end

    -- return message depending on the number of hits
    -- critical miss
    if total_hits < 0 then
        message = player .. " critically misses"
        -- if no shots connect
    elseif total_hits == 0 then
        message = player .. " misses all their shots"
        -- hits less or equal to number of shots
    elseif total_hits <= dN then
        if total_hits > 1 then s = "shots" else s = "shot" end
        message = player .. " hits " .. total_hits .. " " .. s
        .. ", dealing " .. tostring(result_sum) ..
        " (" .. table.concat(dmg_rolls, ", ") .. ")" .. " total damage"
        -- criticals
    elseif total_hits > dN then
        message = player .. " critically hits for " .. tostring(result_sum)
        .. " (" .. table.concat(dmg_rolls, ", ") .. ")" .. " total damage"
    end
    return message
end

function roll_to_hit(player, bN)
    to_hit_msg = player .. " rolls "
    to_hit = math.random(1, 10)
    to_hit_msg = to_hit_msg .. tostring(to_hit)
    if to_hit >= bN then
        if to_hit == 10 then
            to_hit_msg = to_hit_msg .. " and critically hits"
            printToAll(to_hit_msg)
            return 2
        else
            to_hit_msg = to_hit_msg .. " and hits"
            printToAll(to_hit_msg)
            return 1
        end
    elseif to_hit == 1 then
        to_hit_msg = to_hit_msg .. " and critically misses"
        printToAll(to_hit_msg)
        return -1
    else
        to_hit_msg = to_hit_msg .. " and misses"
        printToAll(to_hit_msg)
        return 0
    end
end

function targeted_shot(bN)
    targeted_roll = math.random(1, 12)
end

function roll_button(clicked_object, player)
    message_output(clicked_object, player, self.getDescription())
end

function message_output(clicked_object, player, description)
    is_targeted = false
    if string.find(description, "T") then is_targeted = true end

    message = string.gsub(description, "(%d+)d%[(%d+)%-(%d+)%]b(%d+)",
        function (dice, upper, lower, base)
            return roll_for_damage(dice, upper, lower, base, is_targeted, player)
        end
    )
    printToAll(message)
end

function onSave()
    local data = JSON.encode({desc = self.getDescription()})
    return data
end