eyecheck fix (#4212)

# About the pull request

<!-- Remove this text and explain what the purpose of your PR is.

Mention if you have tested your changes. If you changed a map, make sure
you used the mapmerge tool.
If this is an Issue Correction, you can type "Fixes Issue #169420" to
link the PR to the corresponding Issue number #169420.

Remember: something that is self-evident to you might not be to others.
Explain your rationale fully, even if you feel it goes without saying.
-->

# Explain why it's good for the game
fixes #4190 
bug bad

# Testing Photographs and Procedure
<details>
<summary>Screenshots & Videos</summary>

Put screenshots and videos here with an empty line between the
screenshots and the `<details>` tags.

</details>


# Changelog
:cl:
fix: Glasses with flash protection can no longer be used for welding.
refactor: Adds defines for negative welding protection.
/:cl:

---------

Co-authored-by: harryob <[email protected]>

code/__DEFINES/conflict.dm

@@ -220,6 +220,7 @@
 #define UNIFORM_HAS_SENSORS 1
 #define UNIFORM_FORCED_SENSORS 2
 
+#define EYE_PROTECTION_NEGATIVE -1
 #define EYE_PROTECTION_NONE 0
 #define EYE_PROTECTION_FLAVOR 1
 #define EYE_PROTECTION_FLASH 2

code/game/objects/items/tools/maintenance_tools.dm

@@ -380,22 +380,27 @@
 		if(E.robotic == ORGAN_ROBOT)
 			return
 		switch(safety)
-			if(1)
+			if(EYE_PROTECTION_FLASH)
+				to_chat(user, SPAN_DANGER("You see a bright light in the corner of your vision."))
+				E.take_damage(rand(0, 1), TRUE)
+				if(E.damage > 10)
+					E.take_damage(rand(3, 5), TRUE)
+			if(EYE_PROTECTION_FLAVOR)
 				to_chat(user, SPAN_DANGER("Your eyes sting a little."))
 				E.take_damage(rand(1, 2), TRUE)
-				if(E.damage > 12)
-					H.AdjustEyeBlur(3,6)
-			if(0)
+				if(E.damage > 8) // dont abuse your funny flavor glasses
+					E.take_damage(2, TRUE)
+			if(EYE_PROTECTION_NONE)
 				to_chat(user, SPAN_WARNING("Your eyes burn."))
-				E.take_damage(rand(2, 4), TRUE)
+				E.take_damage(rand(3, 4), TRUE)
 				if(E.damage > 10)
 					E.take_damage(rand(4, 10), TRUE)
-			if(-1)
+			if(EYE_PROTECTION_NEGATIVE)
 				to_chat(user, SPAN_WARNING("Your thermals intensify [src]'s glow. Your eyes itch and burn severely."))
 				H.AdjustEyeBlur(12,20)
 				E.take_damage(rand(12, 16), TRUE)
 
-		if(safety < 2)
+		if(safety < EYE_PROTECTION_WELDING)
 			if (E.damage >= E.min_broken_damage)
 				to_chat(H, SPAN_WARNING("You go blind! Maybe welding without protection wasn't such a great idea..."))
 				return FALSE

code/modules/clothing/glasses/night.dm

@@ -15,6 +15,7 @@
 	vision_flags = SEE_TURFS
 	lighting_alpha = LIGHTING_PLANE_ALPHA_MOSTLY_INVISIBLE
 	fullscreen_vision = null
+	eye_protection = EYE_PROTECTION_NEGATIVE
 
 /obj/item/clothing/glasses/night/helmet //for the integrated NVGs that are in helmetgarb code
 	name = "\improper M2 night vision goggles"

code/modules/clothing/glasses/thermal.dm

@@ -12,7 +12,7 @@
 	lighting_alpha = LIGHTING_PLANE_ALPHA_MOSTLY_INVISIBLE
 	darkness_view = 12
 	invisa_view = 2
-	eye_protection = -1
+	eye_protection = EYE_PROTECTION_NEGATIVE
 	deactive_state = "goggles_off"
 	fullscreen_vision = /atom/movable/screen/fullscreen/thermal
 	var/blinds_on_emp = TRUE