crsn/crsn_screen/src/parse.rs

use crsn::asm::data::{Rd};
use crsn::asm::error::CrsnError;
use crsn::asm::instr::op::OpKind;
use crsn::asm::parse::arg_parser::TokenParser;
use crsn::module::ParseRes;

use crate::defs::ScreenOp;
use crsn::sexp::SourcePosition;

pub(crate) fn parse<'a>(pos: SourcePosition, keyword: &str, mut args: TokenParser<'a>) -> Result<ParseRes<'a, OpKind>, CrsnError> {
    Ok(ParseRes::ext(match keyword {
        "sc-init" => {
            ScreenOp::ScreenInit {
                width: args.next_rd()?,
                height: args.next_rd()?,
            }
        }

        "sc-erase" => {
            ScreenOp::Erase {
                color: if args.len() > 0 {
                    args.next_rd()?
                } else {
                    Rd::immediate(0) // black
                },
            }
        }

        "sc-px" => {
            ScreenOp::SetPixel {
                x: args.next_rd()?,
                y: args.next_rd()?,
                color: args.next_rd()?,
            }
        }

        "sc-opt" => {
            ScreenOp::SetOpt {
                opt: args.next_rd()?,
                val: args.next_rd()?,
            }
        }

        "sc-blit" => {
            ScreenOp::Blit {
                force: if args.have_more() {
                    args.next_rd()?
                } else {
                    Rd::immediate(1)
                },
            }
        }

        "sc-poll" => {
            ScreenOp::Update
        }

        "sc-mouse" => {
            ScreenOp::GetMouse {
                x: args.next_wr()?,
                y: args.next_wr()?,
            }
        }

        "sc-key" => {
            ScreenOp::TestKey {
                pressed: args.next_wr()?,
                code: args.next_rd()?
            }
        }

        "sc-mbtn" => {
            ScreenOp::TestMouse {
                pressed: args.next_wr()?,
                button: args.next_rd()?
            }
        }

        _other => {
            return Ok(ParseRes::Unknown(args));
        }
    }))
}