Handling headers using utl_file upload procedure in oracle - oracle

Question

I am trying to upload a csv file having headers into a table using UTL_FILE, but I am facing an issue. With normal upload using utl_file, the headers are also included and the data results to be recorded in double quotes(which I don't require). If I exclude headers by using an if condition as in below code and declaring headline variable, it uploads the records without headers but still in double quotes. When I manually remove headers from csv file it uploads fine without quotes. But the csv is created newly every day so headers can't be removed from file.
Please suggest some solution which matches the headers between target table and csv then uploads the csv file data. Below is my procedure.
create or replace procedure load_file_new(p_FileDir in varchar2, p_FileName in varchar2)
as
v_FileHandle utl_file.file_type;
v_NewLine varchar2(2000);
v_a varchar2(100);
v_b varchar2(100);
v_c varchar2(100);
v_d varchar2(100);
p_ignore_headerlines number;
begin
v_FileHandle := utl_file.fopen(p_FileDir, p_FileName, 'r', 32767);
p_ignore_headerlines := 1;
if p_ignore_headerlines > 0
then
begin
for i in 1 .. p_ignore_headerlines
loop
utl_file.get_line(v_FileHandle, v_NewLine);
end loop;
end;
end if;
loop
begin
utl_file.get_line(v_FileHandle, v_NewLine);
exception
when no_data_found then
exit;
end;
v_a := regexp_substr(v_NewLine, '("[^"]*"|[^,]+)', 1, 1);
v_b := regexp_substr(v_NewLine, '("[^"]*"|[^,]+)', 1, 2);
v_c := regexp_substr(v_NewLine, '("[^"]*"|[^,]+)', 1, 3);
v_d := regexp_substr(v_NewLine, '("[^"]*"|[^,]+)', 1, 4);
merge into test using dual on (a = v_a)
when not matched then insert (a, b, c, d)
values (v_a, v_b, v_c, v_d)
when matched then update set
b = v_b, c = v_c, d = v_d where a = v_a;
end loop;
utl_file.fclose(v_FileHandle);
commit;
end load_file_new;