Karma means action and refers to actions of your body, speech, and mind. The effects of karma are related to your intentions in these actions of body, speech and mind. Regarding your question:
"If there are "unwholesome" (since i don't know what are wholesome or unwholesome aside from causing direct harm with no ill intentions) thoughts, is this considered thought crime in Buddhism?"
We don't have control over what thoughts arise in our minds. We only have control over what we do with a thought once it's arisen. Do we act on that thought? Or discard it as unwholesome if we recognize it as being connected to greed/desire, hate/anger, or ignorance/delusion? Do we dwell on it? Or move on?
Here is how the Buddha explained it in Dvedhavitakka Sutta: Two Sorts of Thinking:
The Blessed One said, "Monks, before my self-awakening, when I was still just an unawakened Bodhisatta, the thought occurred to me: 'Why don't I keep dividing my thinking into two sorts?' So I made thinking imbued with sensuality, thinking imbued with ill will, & thinking imbued with harmfulness one sort, and thinking imbued with renunciation, thinking imbued with non-ill will, & thinking imbued with harmlessness another sort.
"And as I remained thus heedful, ardent, & resolute, thinking imbued with sensuality arose in me. I discerned that 'Thinking imbued with sensuality has arisen in me; and that leads to my own affliction or to the affliction of others or to the affliction of both. It obstructs discernment, promotes vexation, & does not lead to Unbinding.'
"As I noticed that it leads to my own affliction, it subsided. As I noticed that it leads to the affliction of others... to the affliction of both... it obstructs discernment, promotes vexation, & does not lead to Unbinding, it subsided. Whenever thinking imbued with sensuality had arisen, I simply abandoned it, dispelled it, wiped it out of existence.
The sutta goes on to describe the process of similarly abandoning thoughts of ill will and harmfulness in the same way for the same reasons, that it "leads to my own affliction or to the affliction of others or to the affliction of both. It obstructs discernment, promotes vexation, & does not lead to Unbinding.".