#include "lex-internal.h"

static enum bshell_status word_symbol(struct bshell_lex_ctx *ctx)
{
	const struct bshell_lex_token_definition *sym = NULL;
	enum bshell_status status = read_symbol(ctx, &sym);

	if (status != BSHELL_SUCCESS) {
		return status;
	}

	struct bshell_lex_token *tok = NULL;

	switch (sym->id) {
	case BSHELL_SYM_DOLLAR_LEFT_PAREN:
		status = push_symbol(ctx, sym->id);
		if (status != BSHELL_SUCCESS) {
			return status;
		}

		lex_state_push(ctx, BSHELL_LEX_STATE_STATEMENT, 0);
		return BSHELL_SUCCESS;
	case BSHELL_SYM_RIGHT_PAREN:
		lex_state_pop(ctx);

		status = push_symbol(ctx, sym->id);
		if (status != BSHELL_SUCCESS) {
			return status;
		}
		return BSHELL_SUCCESS;
	case BSHELL_SYM_DOLLAR:
		status = read_var(ctx, BSHELL_TOK_VAR, &tok);
		if (status != BSHELL_SUCCESS) {
			return status;
		}

		enqueue_token(ctx, tok);
		return status;
	case BSHELL_SYM_AT:
		status = read_var(ctx, BSHELL_TOK_VAR_SPLAT, &tok);
		if (status != BSHELL_SUCCESS) {
			return status;
		}

		enqueue_token(ctx, tok);
		return status;
	default:
		break;
	}

	return BSHELL_ERR_BAD_SYNTAX;
}

static enum bshell_status word_content(struct bshell_lex_ctx *ctx)
{
	fx_wchar c = FX_WCHAR_INVALID;
	fx_string *temp = lex_state_get_tempstr(ctx);
	set_token_start(ctx);
	fx_string_clear(temp);

	while (1) {
		c = peek_char(ctx);
		if (c == FX_WCHAR_INVALID) {
			/* EOF without end of word */
			ctx->lex_status = BSHELL_ERR_BAD_SYNTAX;
		}

		if (fx_wchar_is_space(c)) {
			break;
		}

		if (char_can_begin_symbol(ctx, c)) {
			break;
		}

		fx_string_append_wc(temp, c);
		set_token_end(ctx);
		advance_char(ctx);
	}

	if (fx_string_get_size(temp, FX_STRLEN_NORMAL) == 0) {
		return BSHELL_SUCCESS;
	}

	struct bshell_lex_token *tok = bshell_lex_token_create_with_string(
		BSHELL_TOK_WORD,
		fx_string_get_cstr(temp));
	enqueue_token(ctx, tok);

	return BSHELL_SUCCESS;
}

static enum bshell_status word_begin(struct bshell_lex_ctx *ctx)
{
	struct bshell_lex_token *tok = bshell_lex_token_create(BSHELL_TOK_WORD_START);
	if (!tok) {
		return BSHELL_ERR_NO_MEMORY;
	}

	enqueue_token_with_coordinates(
		ctx,
		tok,
		&ctx->lex_start,
		&ctx->lex_start);
	return BSHELL_SUCCESS;
}

static enum bshell_status word_end(struct bshell_lex_ctx *ctx)
{
	struct bshell_lex_token *tok = bshell_lex_token_create(BSHELL_TOK_WORD_END);
	if (!tok) {
		return BSHELL_ERR_NO_MEMORY;
	}

	enqueue_token_with_coordinates(ctx, tok, &ctx->lex_end, &ctx->lex_end);
	return BSHELL_SUCCESS;
}

static enum bshell_status word_pump_token(struct bshell_lex_ctx *ctx)
{
	fx_wchar c = peek_char(ctx);

	if (fx_wchar_is_space(c)) {
		lex_state_pop(ctx);
		return BSHELL_SUCCESS;
	}

	if (char_has_flags(ctx, c, BSHELL_LEX_TOKEN_TERMINATES_WORD)) {
		lex_state_pop(ctx);
		return BSHELL_SUCCESS;
	}

	if (char_can_begin_symbol(ctx, c)) {
		return word_symbol(ctx);
	}

	return word_content(ctx);
}

static const unsigned int symbols[] = {
	BSHELL_SYM_AMPERSAND,
	BSHELL_SYM_HASH,
	BSHELL_SYM_DOLLAR,
	BSHELL_SYM_DOLLAR_LEFT_PAREN,
	BSHELL_SYM_DOLLAR_LEFT_BRACE,
	BSHELL_SYM_PIPE,
	BSHELL_SYM_COMMA,
	BSHELL_SYM_SEMICOLON,
	BSHELL_SYM_LEFT_BRACE,
	BSHELL_SYM_RIGHT_BRACE,
	BSHELL_SYM_LEFT_PAREN,
	BSHELL_SYM_RIGHT_PAREN,
	BSHELL_SYM_NONE,
};

const struct bshell_lex_state_type lex_word_state = {
	.s_id = BSHELL_LEX_STATE_WORD,
	.s_begin = word_begin,
	.s_end = word_end,
	.s_pump_token = word_pump_token,
	.s_symbols = symbols,
};