So many sins in this sineful problem !!!!!

If $a,b,c∈(0,π)$ and $a+b+c=π$ ,

Then, Find the value of

$\begin{aligned} &\sin(b).\sin(c).\sin(b-c)(\sin^2(b)+\sin^2(c)+\sin^2(b-c))+ \\ &\sin(c).\sin(a)\sin(c-a)(\sin^2(c)+\sin^2(a)+\sin^2(c-a))+ \\ &\sin(a).\sin(b).\sin(a-b)(\sin^2(a)+\sin^2(b)+ \sin^2(a-b))+ \\ &\sin(b-c)\sin(c-a)\sin(a-b)(\sin^2(b-c)+\sin^2(c-a)+\sin^2(a-b)) \end{aligned}$