#include "ctx.h"

#include <ivy/lang/parse.h>
#include <stdlib.h>
#include <string.h>

enum ivy_status ivy_parser_create(struct ivy_parser **parser)
{
	struct ivy_parser *out = malloc(sizeof *out);
	if (!out) {
		return IVY_ERR_NO_MEMORY;
	}

	memset(out, 0x0, sizeof *out);

	*parser = out;
	return IVY_OK;
}

void ivy_parser_destroy(struct ivy_parser *parser)
{
	free(parser);
}

enum ivy_status ivy_parser_set_diag_ctx(
	struct ivy_parser *parser, struct ivy_diag_ctx *ctx)
{
	parser->p_diag = ctx;
	return IVY_OK;
}

enum ivy_status ivy_parser_get_status(struct ivy_parser *parser)
{
	return parser->p_status;
}

enum ivy_status ivy_parser_parse(
	struct ivy_parser *parser, struct ivy_lexer *src, struct ivy_ast_node **out)
{
	parser->p_src = src;
	enum ivy_status status = parse_unit(parser, out);
	if (status == IVY_ERR_EOF && *out != NULL) {
		status = IVY_OK;
	}

	return status;
}

struct ivy_token *peek_token(struct ivy_parser *parser)
{
	fx_queue_entry *entry = fx_queue_first(&parser->p_tokens);
	if (!entry) {
		return ivy_lexer_peek(parser->p_src);
	}

	return fx_unbox(struct ivy_token, entry, t_entry);
}

struct ivy_token *peek_next_token(struct ivy_parser *parser)
{
	if (fx_queue_empty(&parser->p_tokens)) {
		struct ivy_token *tok = parse_token(parser);
		fx_queue_push_back(&parser->p_tokens, &tok->t_entry);
		return ivy_lexer_peek(parser->p_src);
	}

	fx_queue_entry *buf = fx_queue_first(&parser->p_tokens);
	if (buf) {
		buf = fx_queue_next(buf);
	}

	if (buf) {
		return fx_unbox(struct ivy_token, buf, t_entry);
	}

	return ivy_lexer_peek(parser->p_src);
}

struct ivy_token *parse_token(struct ivy_parser *parser)
{
	fx_queue_entry *entry = fx_queue_pop_front(&parser->p_tokens);
	if (!entry) {
		return ivy_lexer_read(parser->p_src);
	}

	return fx_unbox(struct ivy_token, entry, t_entry);
}

void discard_token(struct ivy_parser *parser)
{
	struct ivy_token *tok = parse_token(parser);
	if (tok) {
		ivy_token_destroy(tok);
	}
}

void __parse_trace(
	struct ivy_parser *parser, const char *func, int line,
	const char *format, ...)
{
	struct ivy_token *tok = NULL;
	if (parser) {
		tok = peek_token(parser);
		if (tok) {
			fprintf(stderr, "[%zu:%zu] ", tok->t_start.c_row,
			        tok->t_start.c_col);
		} else {
			fprintf(stderr, "[EOF] ");
		}
	} else {
		fprintf(stderr, "[UNK] ");
	}

	fprintf(stderr, "%s:%d: ", func, line);

	if (tok) {
		fprintf(stderr, "(%s) ", ivy_token_to_string(tok));
	}

	va_list va;
	va_start(va, format);
	vfprintf(stderr, format, va);
	va_end(va);

	fputc('\n', stderr);
}