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use solana_program::{
    account_info::AccountInfo,
    entrypoint::ProgramResult,
    program::{invoke, invoke_signed},
    pubkey::Pubkey,
    rent::Rent,
    system_instruction,
};

pub fn create_account<'a, 'info>(
    payer: &'a AccountInfo<'info>,
    new_account: &'a AccountInfo<'info>,
    system_program: &'a AccountInfo<'info>,
    program_owner: &Pubkey,
    rent: &Rent,
    space: u64,
    seeds: Vec<Vec<u8>>,
) -> ProgramResult {
    let current_lamports = **new_account.try_borrow_lamports()?;
    if current_lamports == 0 {
        // If there are no lamports in the new account, we create it with the create_account instruction
        invoke_signed(
            &system_instruction::create_account(
                payer.key,
                new_account.key,
                rent.minimum_balance(space as usize),
                space,
                program_owner,
            ),
            &[payer.clone(), new_account.clone(), system_program.clone()],
            &[seeds
                .iter()
                .map(|seed| seed.as_slice())
                .collect::<Vec<&[u8]>>()
                .as_slice()],
        )
    } else {
        // Fund the account for rent exemption.
        let required_lamports = rent
            .minimum_balance(space as usize)
            .max(1)
            .saturating_sub(current_lamports);
        if required_lamports > 0 {
            invoke(
                &system_instruction::transfer(payer.key, new_account.key, required_lamports),
                &[payer.clone(), new_account.clone(), system_program.clone()],
            )?;
        }
        // Allocate space.
        invoke_signed(
            &system_instruction::allocate(new_account.key, space),
            &[new_account.clone(), system_program.clone()],
            &[seeds
                .iter()
                .map(|seed| seed.as_slice())
                .collect::<Vec<&[u8]>>()
                .as_slice()],
        )?;
        // Assign to the specified program
        invoke_signed(
            &system_instruction::assign(new_account.key, program_owner),
            &[new_account.clone(), system_program.clone()],
            &[seeds
                .iter()
                .map(|seed| seed.as_slice())
                .collect::<Vec<&[u8]>>()
                .as_slice()],
        )
    }
}