substr added

SCRIPTING.md

@@ -54,8 +54,9 @@ In general, scripts conform to the following BNF:
 	     system <expr> |
              <action> <action>
 
-<expr> ::= <val> | <val> <op> <expr> | (<expr>) | not (<expr>) | |
-           retained_topic(<expr>) | json_parse (<expr>,<expr>)
+<expr> ::= <val> | <val> <op> <expr> | (<expr>) | not (<expr>) |
+           retained_topic(<expr>) | substr(<expr>,<num>,<num>) |
+           json_parse (<expr>,<expr>)
 
 <op> := '=' | '>' | gte | str_ge | str_gte | '+' | '-' | '*' | '|' | div
 
@@ -205,6 +206,11 @@ retained_topic(<expr>)
 ```
 Interpretes the argument as topic name (incl. wildcards) and searches the first local retained topic that matches this name. The stored value of this topic is returned (empty, if nothing found). Can be used to check the status of the system synchronously without the need to subscribe for that retained topic, wait for status changes and store them in a variable.
 
+```
+substr(<expr>,<num>,<num>)
+```
+Extracts characters from a string. The two constant numbers give the starting position (first is postion 0) and the length. If the starting position is negative (write it with colons as e.g. "-2"), it counts backwards from the end of the string.
+
 ```
 json_parse (<expr>,<expr>)
 ```

firmware/sha1sums

@@ -1,2 +1,2 @@
-11cc1192f65e4ee3c3b1c447b216d63f59c3a990  0x00000.bin
-9c255dfd53c2790e94718e94fb47774791831f3f  0x10000.bin
+327db48ec28bee48fd33c356c77c8caa6c1ddd0e  0x00000.bin
+43bb3f6fbf04f4bdf9b736998fd9c9fd192093c1  0x10000.bin

scripts/script.sunset

@@ -0,0 +1,69 @@
+% Config params, overwrite any previous settings from the commandline
+% Nothing here
+
+% Now the events, checked whenever something happens
+
+% Now the initialization, this is done once after booting
+on init
+do
+	% Enter your local coordinates here:
+	setvar $service_url = "https://api.sunrise-sunset.org/json?lat=50.734579&lng=7.090007&date=today&formatted=0"
+
+	% Daily lookup time
+	setalarm 3 01:00:00
+
+on wificonnect
+do
+	println $service_url
+	http_get $service_url
+
+	% Retry on no response
+	settimer 1 20000
+
+on http_response
+do
+	println "return code: " | $this_http_code
+	if not($this_http_code = 200) then
+		% Retry on failue
+		settimer 1 20000
+	else
+		settimer 1 0
+		println $this_http_body
+
+		setvar $sunrise = substr(json_parse("results.sunrise", $this_http_body), 11, 8)
+		setvar $sunset = substr(json_parse("results.sunset", $this_http_body), 11, 8)
+
+		println "Sunrise: " | $sunrise
+		println "Sunset: " | $sunset
+
+		setalarm 1 $sunset
+		setalarm 2 $sunrise
+	endif
+
+% Retry timer
+on timer 1
+do
+	println "Retry: " | $service_url
+	http_get $service_url	
+
+% Switch on 
+on alarm 1
+do
+	publish local /time/sunset $sunset
+
+	println "Sunset - switch on at " | $timestamp  
+	gpio_out 2 0
+
+% Switch off 
+on alarm 2
+do
+	publish local /time/sunrise $sunrise
+
+	println "Sunrise - switch off at " | $timestamp 
+	gpio_out 2 1
+
+% Get new values
+on alarm 3
+do
+	println $service_url
+	http_get $service_url

user/lang.c

@@ -1131,6 +1131,64 @@ int ICACHE_FLASH_ATTR parse_expression(int next_token, char **data, int *data_le
 	    }
 	}
     }
+    else if (is_token(next_token, "substr")) {
+	lang_debug("val substr\r\n");
+
+	len_check(7);
+	if (syn_chk && !is_token(next_token+1, "("))
+	    return syntax_error(next_token+1, "expected '('");
+
+	char *str_data;
+	int str_data_len;
+	Value_Type str_data_type;
+	// parse path string
+	if ((next_token = parse_expression(next_token + 2, &str_data, &str_data_len, &str_data_type, doit)) == -1)
+	    return -1;
+	if (!doit)
+	    str_data_len = 0;
+	char str[str_data_len+1];
+	if (doit)
+	    os_strcpy(str, str_data);
+
+	if (syn_chk && !is_token(next_token, ","))
+	    return syntax_error(next_token, "expected ','");
+	next_token++;
+
+	int16_t from = atoi(my_token[next_token]);
+	// if as string const
+	if (my_token[next_token][0] == '"')
+	    from = atoi(&my_token[next_token][1]);
+	next_token++;
+
+	if (syn_chk && !is_token(next_token, ","))
+	    return syntax_error(next_token, "expected ','");
+	next_token++;
+
+	uint16_t len = atoi(my_token[next_token]);
+	next_token++;
+
+	if (syn_chk && !is_token(next_token, ")"))
+	    return syntax_error(next_token, "expected ')'");
+	next_token++;
+
+	if (doit) {
+	    if (from < 0) {
+		from = str_data_len+from;
+		if (from < 0)
+		    from = 0;
+	    }
+
+	    if (len+1 > sizeof(tmp_buffer))
+		len = sizeof(tmp_buffer)-1;
+
+	    os_strncpy(tmp_buffer, &str[from], len);
+	    tmp_buffer[len] = '\0';
+
+	    *data_len = len;
+	    *data = tmp_buffer;
+	    *data_type = STRING_T;
+	}
+    }
 #ifdef GPIO
     else if (is_token(next_token, "gpio_in")) {
 	lang_debug("val gpio_in\r\n");