feat: add milestone goals for early progression

scripts/milestone_manager.gd

@@ -0,0 +1,136 @@
+class_name MilestoneManager
+# Fixed early-game milestone goals for Windowstead.
+# See misospace/windowstead#132.
+#
+# Milestones sit above rotating micro-goals: they are a small,
+# fixed progression chain that gives the player a sense of
+# early-game direction without replacing the ambient desktop-
+# companion feel.
+#
+# Evaluation is pure-data (reads game_state dictionaries only).
+# Completion state persists in save data.
+
+const MILESTONE_TYPE_BUILD := "build"
+const MILESTONE_TYPE_STOCKPILE := "stockpile"
+const MILESTONE_TYPE_WORKER := "worker"
+
+# ── Milestone catalog (fixed, deterministic) ────────────────────────────────
+# Each entry defines one step in the early progression chain.
+# Order matters: milestones are evaluated sequentially.
+const MILESTONE_CATALOG := [
+	{
+		"id": "build_hut",
+		"name": "Build a hut",
+		"type": MILESTONE_TYPE_BUILD,
+		"target": {"build_kind": "hut"},
+		"description": "Your first shelter. The crew gets a roof.",
+	},
+	{
+		"id": "stockpile_food",
+		"name": "Stockpile 10 food",
+		"type": MILESTONE_TYPE_STOCKPILE,
+		"target": {"resource": "food", "amount": 10},
+		"description": "The larder is filling up. Rations secured.",
+	},
+	{
+		"id": "build_workshop",
+		"name": "Build a workshop",
+		"type": MILESTONE_TYPE_BUILD,
+		"target": {"build_kind": "workshop"},
+		"description": "A proper workspace. Things are getting serious.",
+	},
+	{
+		"id": "build_garden",
+		"name": "Build a garden",
+		"type": MILESTONE_TYPE_BUILD,
+		"target": {"build_kind": "garden"},
+		"description": "Fresh greens on the horizon. Self-sufficient vibes.",
+	},
+	{
+		"id": "support_third_worker",
+		"name": "Support a third worker",
+		"type": MILESTONE_TYPE_WORKER,
+		"target": {"worker_count": 3},
+		"description": "A full crew. The colony is growing.",
+	},
+]
+
+# ── Active goal state (per-save) ────────────────────────────────────────────
+# {
+#   "milestone_id": String,    # ID of the current milestone from catalog
+#   "completed_ids": Array     # IDs of previously completed milestones
+# }
+
+# ── Create a fresh milestone goal state ─────────────────────────────────────
+static func make_goal_state() -> Dictionary:
+	return {
+		"milestone_id": MILESTONE_CATALOG[0]["id"],
+		"completed_ids": [],
+	}
+
+# ── Get the current milestone definition from catalog ────────────────────────
+static func get_current_milestone(catalog: Array, milestone_id: String) -> Dictionary:
+	for entry in catalog:
+		if entry.get("id") == milestone_id:
+			return entry.duplicate(true)
+	return {}
+
+# ── Progress evaluation (pure data, reads game_state) ────────────────────────
+
+# Evaluate whether the current milestone is complete given game state.
+# Returns {progress: int, total: int} for UI progress display.
+static func evaluate_milestone(milestone: Dictionary, game_state: Dictionary) -> Dictionary:
+	var mtype := String(milestone.get("type", ""))
+	var target := milestone.get("target", {})
+
+	match mtype:
+		MILESTONE_TYPE_BUILD:
+			var build_kind := String(target.get("build_kind", ""))
+			var builds := game_state.get("builds", [])
+			for build in builds:
+				if bool(build.get("complete")) and String(build.get("kind", "")) == build_kind:
+					return {"progress": 1, "total": 1}
+			return {"progress": 0, "total": 1}
+
+		MILESTONE_TYPE_STOCKPILE:
+			var resource := String(target.get("resource", ""))
+			var amount := int(target.get("amount", 0))
+			var harvested := game_state.get("harvested", {})
+			var current := int(harvested.get(resource, 0))
+			return {"progress": mini(current, amount), "total": amount}
+
+		MILESTONE_TYPE_WORKER:
+			var count := int(target.get("worker_count", 0))
+			var workers := game_state.get("workers", [])
+			var active := 0
+			for worker in workers:
+				if int(worker.get("break_ticks", 0)) <= 0:
+					active += 1
+			return {"progress": mini(active, count), "total": count}
+
+		_:
+			return {"progress": 0, "total": 1}
+
+# ── Completion check ────────────────────────────────────────────────────────
+static func is_milestone_complete(milestone: Dictionary, game_state: Dictionary) -> bool:
+	var eval := evaluate_milestone(milestone, game_state)
+	return eval.get("progress", 0) >= eval.get("total", 1)
+
+# ── Advance to next milestone ───────────────────────────────────────────────
+static func advance_to_next(completed_ids: Array, current_id: String) -> String:
+	# Find the index of the current milestone in the catalog
+	var current_index := -1
+	for i in range(MILESTONE_CATALOG.size()):
+		if MILESTONE_CATALOG[i]["id"] == current_id:
+			current_index = i
+			break
+
+	if current_index < 0 or current_index >= MILESTONE_CATALOG.size() - 1:
+		return current_id  # No next milestone
+
+	var next_index := current_index + 1
+	return MILESTONE_CATALOG[next_index]["id"]
+
+# ── Milestone description for event log ─────────────────────────────────────
+static func milestone_description(milestone: Dictionary) -> String:
+	return String(milestone.get("description", "A new milestone."))