#include <errno.h>
#include <math.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "ir.h"
#include "lex.h"
#include "parse.h"
#include "util.h"

static void usage(const char *prgname);
static void die(const char *fmt, ...);

static void usage(const char *prgname) {
	fprintf(stderr, "Usage:\n"
			"  %s [OPTIONS] <FILENAME>\n"
			"Options:\n"
			"  -emit-tokens\n"
			"  -emit-ir\n"
			"  -dry             --  don't execute the script (just process it)\n"
			, prgname);
}

static void die(const char *fmt, ...) {
	fprintf(stderr, C_IRED "Error: " C_RESET);
	va_list va;
	va_start(va, fmt);
	vfprintf(stderr, fmt, va);
	va_end(va);
	exit(1);
}

int main(int argc, const char **argv) {
	/* parse arguments */
	size_t nargs = argc - 1;
	const char *prgname = argv[0];
	const char **args = argv + 1;
	bool opt_emit_tokens = false;
	bool opt_emit_ir = false;
	bool opt_dry = false;
	const char *filename = NULL;
	for (size_t i = 0; i < nargs; i++) {
		if (args[i][0] == '-') {
			if (streq(args[i], "-h") || streq(args[i], "-help") || streq(args[i], "--help")) {
				usage(prgname);
				return 0;
			} else if (streq(args[i], "-emit-ir"))
				opt_emit_ir = true;
			else if (streq(args[i], "-emit-tokens"))
				opt_emit_tokens = true;
			else if (streq(args[i], "-dry"))
				opt_dry = true;
			else {
				die("Unknown option: %s\n", args[i]);
			}
		} else {
			if (filename) {
				die("Filename already set to '%s'\n", filename);
			}
			filename = args[i];
		}
	}
	if (!filename) {
		die("Please specify a filename\n");
	}
	/* read source file */
	FILE *fp = fopen(filename, "r");
	if (!fp) {
		die("Failed to open '%s': %s\n", filename, strerror(errno));
	}
	char *file = mreadfile(fp);
	if (!file) {
		fclose(fp);
		die("Failed to read '%s': %s\n", filename, strerror(errno));
	}
	fclose(fp);
	/* lex source file */
	TokList tokens = lex(file);
	if (err) {
		toklist_term(&tokens);
		free(file);
		fprintf(stderr, C_IRED "Lexer error" C_RESET " in " C_CYAN "%s" C_RESET ":%zu:%zu: %s\n", filename, err_ln, err_col, errbuf);
		return 1;
	}
	free(file);
	if (opt_emit_tokens)
		print_toks(&tokens);
	/* parse tokens into IR code */
	IRToks ir = parse(&tokens);
	if (err) {
		irtoks_term(&ir);
		toklist_term(&tokens);
		fprintf(stderr, C_IRED "Parser error" C_RESET " in " C_CYAN "%s" C_RESET ":%zu:%zu: %s\n", filename, err_ln, err_col, errbuf);
		return 1;
	}
	toklist_term(&tokens);
	if (opt_emit_ir)
		print_ir(&ir);
	/* run the IR */
	/* TODO... */
	irtoks_term(&ir);
}