extends Resource
class_name Modifier
# One modifier definition: title + description + texture + scoring rule.
# Create instances of this as .tres files in the editor (right-click in
# FileSystem -> New Resource -> Modifier), OR build them in code in the catalog.
#
# Because a texture always maps to the same modifier, the texture lives HERE.

# A stable unique id (e.g. "stars_x5"). Useful for saving which modifiers are
# applied to which segments, and for lookups. Keep it unique across the catalog.
@export var id: String = ""

# Shown to the player when offered the piece.
@export var title: String = ""
@export_multiline var description: String = ""

# The texture painted onto the segment when this modifier is applied.
@export var texture: Texture2D

# --- Scoring rule ---
# Simple, data-only rules cover most cases without writing code per modifier.
# value = (base_value * mult + add) for the affected segment.
@export var score_mult: float = 1.0
@export var score_add: int = 0

# Optional: rarity weight for random selection (higher = more common).
@export var weight: float = 1.0

# Apply this modifier's rule to a segment's base value.
func apply_score(base_value: int) -> int:
	return int(round(base_value * score_mult)) + score_add

# A short human-readable summary of the effect, for tooltips/UI.
func effect_text() -> String:
	var parts: Array[String] = []
	if score_mult != 1.0:
		parts.append("x%s" % str(score_mult))
	if score_add != 0:
		parts.append(("+%d" % score_add) if score_add > 0 else str(score_add))
	return " ".join(parts) if parts.size() > 0 else "no change"
