elemental damage build question

melee lightning damage templar build.
i use lightning strike, tempest shield.
50% physical damage goes lightning damage.

the problem is very complicated to me.. there are passive skills that increase lightning strike's damage.
(ps is passive skill)
elemental damage ps, elemental damage with weapons ps, lightning damage ps, physical damage ps.

i dont know which ones will give me highest dps. i can't get all of them.
50% physical damage goes lightning damage. so must i go physical damage + attack speed than lightning damage and elemental damage?
or will elemental damage + lightning damage passive skills give me highest dps?
or elemental dmg + physical dmg.
or elemental dmg + attack speed.
or elemental dmg + lightning dmg + attack speed.
or elemental dmg + physical dmg + lightning dmg.
or physical dmg + lightning dmg.
or physical dmg + attack speed + lightning dmg.
it seems like there are better elemental skills than lightning skills like catalyse.
it seems like arcing blows + catalyse is weaker than catalyse + 3 weapon elemental damage skills.
(because i get physical damage skills to get weapon elemental damage skill)
and i must waste more skill points to get arcing blows.
there are passive skills that increase lightning damage in witch tree.
total is about 62% in witch tree.
total is about 50% in shadow tree.

or catalyse (40%) + ele dmg skills (10% x3) + physical dmg skills + attack speed skills
VS catalyse (40%) + ele dmg skills (10% x3) + lightning dmg skills (112%) = ?

112% lightning damage is better than every physical damage + attack speed skills?? i am confused because 50% physical dmg goes lightning strike
or 62% + melee physical damage + attack speed. or 50% + melee pdmg. or 80%+pdmg etc..
i think there are more many passive skills of physical damage and attack speed than lightning damage.
but i don't have pure physical damage build or pure lightning damage build.
so i can't see which one has highest dps with lightning strike and tempest shield.
i wish there is some damage simulator thing in game or some program or site. many online games have some kind of dps simulator in the game but poe...

this game needs passive skill and dps simulator function or site.....
when i play gw2 and bns, there was skill gear simulator site.
i could test and see my dps with gears and trait skills in the site.
but there is no a site for path of exile.
or is there any site??