Confused.

I genuinely do not know if he likes me back or is just being nice to me. Basically to give some context about our relationships history, my guy friend and I have always been super close. He tends to not vent to anyone and only vents to me about his problems. We talk by going into group vcs, with rarely of the two of us dming each other. Back in early 2023, I started developing feelings for him. I would always initiate conversations with him daily, and even ask him to hang out every week. But during this time, he has never initiated contact once. At that time, I felt like he didn't return the same feelings that I've had. During this time, he would tease me constantly in a harsh way. When I confessed that I liked him, I got friendzoned.
Now fast forward to late 2023 to now, he's been acting pretty weird around me recently. Like, complimenting me, being super nice to me, and never teases me harshly. He would also tease me about guys he knows I'm not interested in. He even messaged me ily, when he was drunk one night and has vented to me while he was drunk. We would still only have calls in groups of people, but now it shifted to us only having calls with the two of us. We've been calling and texting each other constantly for a week straight, he would even initiate conversations which he has never done before. He's been interested in some of the stuff I've been talking about and he has even gotten some books that are my favorite (romance novels). I asked him a couple days ago if he was willing to be my valentine, and he said yes. I joke around and ask if he would like to go on a date, and he has also said yes. I was joking around with him that I was the only one who initiated flirting and asked if he could flirt back, he said he was willing and even joked about doing it irl.
When finally meeting in person for the first time, he did show signs of being interested in me by sitting close to me all the time when he didn't have to. Constantly trying to stand next to me, when we were at a Korean bbq place and I was showing him something on my phone, he scooted closer towards me to see what I was looking at. There were times when we were far away from each other, he would get up and walk towards where I was. He maintained eye contact with me whenever we talked to each other, was constantly trying to find ways to be around me, and even would go far enough to when if we were ever separated, he would make an excuse to come closer to me by saying he needs to go over there and would just stand right next to me. When it was time to say goodbye to each other, he gave me a very long hug that resulted him to swaying back and forth.
When our first meeting in person was done and we went back to us talking to each other on the phone, he sort of went back to the same behavior he was displaying by harshly teasing me and even said "**** you" to me but I confronted him about it and he just said not for me to take it seriously. He then went on his trip to Japan and ever since he came back from his trip to Japan, a lot of things has changed regarding his behavior. But one thing did happen when he was in Japan and that was when he got drunk one night and texted me "ily" and to some of our friends about it. Ever since he has come back from his trip, he has gotten his job back and it seems like he's going back to his old ways. I remember I was just asking him a question regarding something and he only said "shut up" to me when answering the question and when I asked him another question and he couldn't hear me, he just said I was deaf like before his major shift in behavior where I thought he liked me.
I honestly did think he liked me but now it just seems like he doesn't anymore? It just feels like he's going back to his old ways and I don't know what to do anymore. I'm just really confused on how he feels, and don't know what to do. We used to hang out a lot together alone but now I'm afraid to even ask that anymore because I don't think he likes me like that anymore and now I'm kind of upset about it. When I did message him about watching a show we didn't finish, he never replies to it and just ends up ignoring me. It's just not the same anymore.