2D pathfinder

local tMap=setmetatable({
"01000000000000000101",
"01000000000000000101",
"01111100000000000101",
"00000111111111000101",
"11110110000001000101",
"00000110111101000101",
"01111110001101000101",
"01000011101101000101",
"01000000101101000101",
"01111111101101000101",
"00000000001101000101",
"11111111111101111101",
"00000000000100001101",
"00000000000101111101",
"00000000000101111101",
"00000000000100000001",
"00000000000111111111"
},{__call=function(self,x,y)
    if self[y] and x<=#self[y] then
        return string.sub(self[y],x,x)
    end
end})

local function fPath(map,targx,targy)

    --[VARS]
    local path={x=1,y=1,""}
    local target={x=targx or 1,y=targy or 1}
    local displacement=setmetatable({},{__index=function(self,index) if path[index] and target[index] then return path[index]-target[index] end end,__newindex=function() return nil end})
    local checked=setmetatable({{x=1,y=1}},{__call=function(self,x,y) for k,v in pairs(self) do if v.x==x and v.y==y then return true end end return false end})
    local directions_mt={__index=function(self,index) if index=="x" or index=="y" then return 0 end end}
    local directions=setmetatable({{x=1,"r"},{x=-1,"l"},{y=1,"d"},{y=-1,"u"}},{__call=function(self,direction)
        if direction then
            for k,v in pairs(self) do
                if v[1]==direction then
                    return v
                end
            end
        else
            local x
            local y
            for k,v in pairs(self) do
                if (displacement.x>0 and v.x<0) or (displacement.x<0 and v.x>0) then
                    x=v
                elseif (displacement.y>0 and v.y<0) or (displacement.y<0 and v.y>0) then
                    y=v
                end
            end
            return x,y
        end
    end})
    for k,v in pairs(directions) do setmetatable(v,directions_mt) end

    --[FUNCTIONS]
    local render=function()
        term.clear()
        for k,v in pairs(map) do
            term.setCursorPos(1,k)
            print(({string.gsub(string.gsub(v,"0","."),"1","#")})[1])
        end
        print(path.x..", "..path.y)
        term.setCursorPos(path.x,path.y)
        write("*")
    end

    --[EXECUTION]
    while true do
        local x,y=directions()
        if x and map(path.x+x.x,path.y)=="0" and not checked(path.x+x.x,path.y) then
            path.x=path.x+x.x
            path[1]=path[1]..x[1]
            table.insert(checked,{x=path.x,y=path.y})
        elseif y and map(path.x,path.y+y.y)=="0" and not checked(path.x,path.y+y.y) then
            path.y=path.y+y.y
            path[1]=path[1]..y[1]
            table.insert(checked,{x=path.x,y=path.y})
        else
            local moved=false
            for k,v in pairs(directions) do
                if v~=x and v~=y and map(path.x+v.x,path.y+v.y)=="0" and not checked(path.x+v.x,path.y+v.y) then
                    moved=true
                    path.x=path.x+v.x
                    path.y=path.y+v.y
                    path[1]=path[1]..v[1]
                    table.insert(checked,{x=path.x,y=path.y})
                    break
                end
            end
            if not moved then
                if path.x==1 and path.y==1 then
                    term.clear()
                    term.setCursorPos(1,1)
                    print("no way to get to target...")
                    break
                end
                path.x=path.x-directions(string.sub(path[1],-1)).x
                path.y=path.y-directions(string.sub(path[1],-1)).y
                path[1]=string.sub(path[1],1,-2)
            end
        end
        term.setCursorPos(1,12)
        if path.x==target.x and path.y==target.y then
            term.clear()
            term.setCursorPos(1,1)
            print("target found, path:")
            print(path[1])
            break
        end
        sleep(0.1)
        render()
    end
end

fPath(tMap,19,1)