That's not how it works. A system cannot be "half socialism half capitalism" as these two concepts quite literally contradict each other.

Socialism is the process of transition from capitalism to communism. It's defined by a society where the proletariat has become the ruling class, after having the former ruling class overthrown through revolution; a society where the state serves the interests of the workers and naturally withers away (as Lenin puts it) as the concept of class begins to disappear (as we get closer to communism). For more info on this, you can read state and revolution, by Lenin. As for dialectical and historical materialism, you can read Socialism: utopian and scientific, by Engels and Dialectical and Historical Materialism, by the man of steel himself.

Capitalism is the system that came after feudalism and before Socialism. It's defined by giving full power to the Bourgeoisie and, contrary to under Socialism, the state serves the interests of the Bourgeoisie. Here's a (very) basic explanation of each one:

1. Early capitalism (idk the marxist term for it): Small competition among national bourgeoisie.

2. Monopoly Capitalism: As the nature of Capitalism naturally leads to monopolization, the means of production are at a large scale concentrated in the hands of a few.

3. Imperialism, the highest stage of Capitalism: Capitalism needs infinite growth and expansion to survive, so it exports capital (workers, firms, factories) abroad in order to expand and increase profits.

My definitions might be slightly incorrect, i haven't had the time to read theory in a while due to life circumstances

One could assume China is revisionist for adopting a market economy instead of a strictly planned economy, like the one in the USSR and former Socialist bloc, but this argument is fundamentally wrong, since it's extremely idealistic to think of Socialism as a fixed set of rules that must be forced upon the material conditions of said society and not the other way around (and that's why the "not real socialism" argument doesn't even make any sense). The truth is that, while it'd have been more desirable for China to keep a planned economy, opening up to the West and its capital (under heavy supervision and control of the CPC) allowed China to flourish and become the very industrialized nation that it is today, and I think if Mao could see what his country became, he would be very proud.