Chanter 0.0.1-poc

_addon.name = 'Chanter'
_addon.author = 'Lili'
_addon.version = '0.0.1'
_addon.command = 'chanter'

--[[

Select a target, do //chanter, and it will tell you what bonuses you are getting at what strength.

Cardinal Chant bonuses have 8 tiers. You can calculate specific value with
floor(max value * tier / 8)

At lvl99 GEO has Cardinal Chant IV, with these maximum values for each bonus:
Bonus           Normal Spells   -ra Spells  Direction
Magic Attack        +13             +17     East
Magic Accuracy      +13             +17     South
Magic Burst Bonus   +22             +28     West
Magic Crit. Rate    +11             +16     North

]]

bonus = { N = 'Magic Crit. Chance', S = 'Magic Accuracy',W = 'Magic Burst Bonus', E = 'Magic Attack Bonus', }

windower.register_event('addon command',function(angle, dist)
    local t = windower.ffxi.get_mob_by_target('t')

    if not t then
        windower.add_to_chat(123,'Please select a target.')
        return
    end

    --local me = windower.ffxi.get_mob_by_target('me')
    local h = get_heading_to(t.x,t.y)

    local chant = heading_to_nswe(h)

    local msg = ''
    for d,v in pairs(chant) do
        if v > 0 then
            msg = msg .. bonus[d] ..' ['..v..'/8] '
        end
    end

    windower.add_to_chat(80,msg)
end)

function get_heading_to(x,y) --
    local me = windower.ffxi.get_mob_by_target('me')
    local x = x - me.x
    local y = y - me.y
    local h = math.atan2(x,y)
    return h
    --return h - math.pi/2 -- <- change the above line to this one if you want to use this function together with windower.ffxi.turn()
end

function heading_to_nswe(heading)
    if not heading then return end

    local compass = {N=0,S=0,W=0,E=0}

    -- vertical and horizontal half planes
    local px = 'N'
    local py = heading <= 0 and 'W' or 'E'

    heading = math.abs(heading) -- get rid of sign

    if heading > math.pi/2 then
        heading = math.pi - heading -- flip!
        px = 'S'
    end

    local slice = math.floor( (heading+math.pi/32) / (math.pi/16) ) -- 1-8

    compass[py] = slice
    compass[px] = 8-slice

    return(compass)
end