use std::fs::metadata;
use std::io::stdin;
use std::path::PathBuf;

mod args;
mod makefile;

use args::Args;
use makefile::Makefile;

fn main() {
    let mut args = Args::from_env_and_args();
    // If no makefile is specified, try some options.
    if args.makefile.is_empty() {
        if metadata("./makefile").is_ok() {
            args.makefile = vec!["./makefile".into()];
        } else if metadata("./Makefile").is_ok() {
            args.makefile = vec!["./Makefile".into()];
        } else {
            // TODO handle error gracefully
            panic!("no makefile found");
        }
    }
    // Read in the makefile(s) specified.
    // TODO dump command-line args into MAKEFLAGS
    // TODO dump command-line macros into environment
    // TODO add SHELL macro
    let mut makefile = Makefile::new(args.clone());
    for filename in &args.makefile {
        if filename == &PathBuf::from("-") {
            makefile.and_read(stdin().lock());
        } else {
            makefile.and_read_file(filename);
        };
    }

    if args.print_everything {
        println!("{}", &makefile);
    }

    let targets = if args.targets().count() == 0 {
        vec![makefile.first_non_special_target.clone().expect("couldn't find a target!")]
    } else {
        args.targets().cloned().collect()
    };

    for target in targets {
        makefile.update_target(&target);
    }
}