solana-program-examples/program-basics/recommended-program-layout/native/program/src/instructions/get_on_ride.rs

use solana_program::{
    entrypoint::ProgramResult, 
    msg, 
    program_error::ProgramError,
};

use crate::state::ride;


// InstructionData Data


pub struct GetOnRideInstructionData {
    pub rider_name: String,
    pub rider_height: u32,
    pub rider_ticket_count: u32,
    pub ride: String,
}


pub fn get_on_ride(ix: GetOnRideInstructionData) -> ProgramResult {
    
    let rides_list = ride::get_rides();
    
    for ride in rides_list.iter() {
        
        if ix.ride.eq(&ride.name) {
            
            msg!("You're about to ride the {}!", ride.name);

            if ix.rider_ticket_count < ride.tickets {
                msg!("  Sorry {}, you need {} tickets to ride the {}!", ix.rider_name, ride.tickets, ride.name);
                return Ok(())
            };

            if ix.rider_height < ride.min_height {
                msg!("  Sorry {}, you need to be {}\" tall to ride the {}!", ix.rider_name, ride.min_height, ride.name);
                return Ok(())
            };

            msg!("  Welcome aboard the {}!", ride.name);

            if ride.upside_down {
                msg!("  Btw, this ride goes upside down. Hold on tight!");
            };

            return Ok(())
        }
    }

    Err(ProgramError::InvalidInstructionData)
}