--[[
Component 2x3:

       z+
      /|\
\   22 | 11   /
 \  22 | 11  /
  \ 22 | 11 /
333 \  |  /  000
333   \|/    000
−−−−−−−+−−−−−−−> x+
444   /|\    777
444 /  |  \  777
  / 55 | 66 \
 /  55 | 66  \
/   55 | 66   \
--]]
local function vecTo8dir(vec)
    local x = vec[1]
    local z = vec[3]
    return
        x>=0 and z>=0 and  z<=x and 0 or
        x>=0 and z>=0 and  z>x  and 1 or
        x<0  and z>=0 and -z<=x and 2 or
        x<0  and z>=0 and -z>x  and 3 or
        x<0  and z<0  and  z>=x and 4 or
        x<0  and z<0  and  z<x  and 5 or
        x>=0 and z<0  and -z>=x and 6 or
        x>=0 and z<0  and -z<x  and 7 or
        0 -- Should not happen
end
local function addToPos8dir(dir,pos,w,h)
    local x = pos[1]
    local y = pos[2]
    local z = pos[3]
    return
        dir == 0 and {x = x+h, y = y, z = z+w} or
        dir == 1 and {x = x+w, y = y, z = z+h} or
        dir == 2 and {x = x-w, y = y, z = z+h} or
        dir == 3 and {x = x-h, y = y, z = z+w} or
        dir == 4 and {x = x-h, y = y, z = z-w} or
        dir == 5 and {x = x-w, y = y, z = z-h} or
        dir == 6 and {x = x+w, y = y, z = z-h} or
        dir == 7 and {x = x+h, y = y, z = z-w} or
        pos -- Should not happen
end

-- Removes a node without calling on on_destruct()
-- We use this to mess with bed nodes without causing unwanted recursion.
local function remove_no_destruct(pos)
	minetest.swap_node(pos, {name = "air"})
	minetest.remove_node(pos) -- Now clear the meta
	minetest.check_for_falling(pos)
end

-- Everything is described as if dir=0
-- {name,width,height,{cables_left,cables_right,cables_top,cables_bottom}}
components = {
    "and" = {2,3,{{"in_1","in_2"},{"out"},{},{}}},
    "switch" = {2,1,{{"in"},{"out"},{"activate"},{}}},
    "demux" = {2,8,{{"in_1","in_2","in_3"},{"out_1","out_2","out_3","out_4","out_5","out_6","out_7","out_8"},{},{}}},
}

-- componentsblocks["block"] = {name,x,y}
componentsblocks = {}



minetest.register_node("logikraft:component_head", {
    drawtype = "block",
    tiles = {"component.png"},
    groups = {circuitry = 1,dig_immediate = 3},
    on_place = function(itemstack, placer, pointed_thing)
        local w = 3
        local h = 5

        local under = pointed_thing.under
        local node = minetest.get_node(under)
        local udef = minetest.registered_nodes[node.name]

        -- Rightclick is prioritary
        if udef and udef.on_rightclick and
                not (placer and placer:is_player() and
                placer:get_player_control().sneak) then
            return udef.on_rightclick(under, node, placer, itemstack,
                pointed_thing) or itemstack
        end

        -- Pos will be the head location
        local pos
        if udef and udef.buildable_to then
            pos = under
        else
            pos = pointed_thing.above
        end


        local player_name = placer and placer:get_player_name() or ""

        local dir = placer and placer:get_look_dir() and
            vecTo8dir(placer:get_look_dir()) or 0

        for i = 0,w*h-1 do
            local loc = addToPos8dir(dir,pos,i%w,(i-i%w)/w)
            local node_def = minetest.registered_nodes[minetest.get_node(loc).name]
            if not node_def or not node_def.buildable_to then
                -- Then we cannot build here
                return itemstack
            end
        end
        -- If we reached this point, we can build the component
        minetest.set_node(pos, {name = "logikraft:component_head", param2 = dir})
        for i = 1,w*h-1 do
            local loc = addToPos8dir(dir,pos,i%w,(i-i%w)/w)
            minetest.set_node(loc, {name = "logikraft:component_tail", param2 = dir})
        end

        if not minetest.is_creative_enabled(player_name) then
            itemstack:take_item()
        end
        return itemstack
    end,
    on_destruct = function(pos)
        local w = 3
        local h = 5

        local node = minetest.get_node(pos)
        
        dir = node.param2
        
        remove_no_destruct(pos) -- Should be logikraft:component_head
        for i = 1,w*h-1 do
            local loc = addToPos8dir(dir,pos,i%w,(i-i%w)/w)
            local onode = minetest.get_node(loc)
            if onode.name == "logikraft:component_tail" and onode.param2 == dir
            then
                remove_no_destruct(loc)
            end
        end
        
    end
})

minetest.register_node("logikraft:component_tail", {
    drawtype = "block",
    paramtype2 = "4dir",
    groups = {circuitry = 1},
    -- Which direction is the one of the head block
    tiles = {"component.png^[colorizehsl:120"}
})