-- Measure the redesigned ramps: extent, grade, side (E/W), and collisions
-- with STRUCTURAL parts (piers, masts, girders). Read-only.
local ws = game:GetService("Workspace")
local map = ws:FindFirstChild("Map")
if not map then
	return "no Map"
end

local PA = Vector3.new(-4124, 46, -7470)

-- Gather deck parts per run.
local runs = {}
for _, d in ipairs(map:GetDescendants()) do
	if d:IsA("BasePart") then
		local nm = d.Name
		for _, base in ipairs({ "PAEntryRampTrunk", "PAEntryRampNear", "PAExitRampTrunk", "PAExitRampNear" }) do
			if nm:sub(1, #base) == base then
				runs[base] = runs[base] or {}
				table.insert(runs[base], d)
			end
		end
	end
end

local out = {}
local order = { "PAEntryRampTrunk", "PAEntryRampNear", "PAExitRampTrunk", "PAExitRampNear" }
for _, base in ipairs(order) do
	local parts = runs[base]
	if not parts then
		table.insert(out, base .. ": MISSING")
	else
		local minY, maxY = math.huge, -math.huge
		local minX, maxX = math.huge, -math.huge
		local minZ, maxZ = math.huge, -math.huge
		local maxGrade = 0
		table.sort(parts, function(a, b)
			return a.Name < b.Name
		end)
		for _, p in ipairs(parts) do
			local q = p.Position
			minY, maxY = math.min(minY, q.Y), math.max(maxY, q.Y)
			minX, maxX = math.min(minX, q.X), math.max(maxX, q.X)
			minZ, maxZ = math.min(minZ, q.Z), math.max(maxZ, q.Z)
		end
		for i = 2, #parts do
			local a, b = parts[i - 1].Position, parts[i].Position
			local horiz = (Vector3.new(a.X, 0, a.Z) - Vector3.new(b.X, 0, b.Z)).Magnitude
			if horiz > 0.5 then
				maxGrade = math.max(maxGrade, math.abs(b.Y - a.Y) / horiz * 100)
			end
		end
		-- mean X relative to PA centre tells us east (+) or west (-)
		local sx = 0
		for _, p in ipairs(parts) do
			sx += p.Position.X
		end
		local side = (sx / #parts) > PA.X and "EAST" or "WEST"
		table.insert(
			out,
			("%s: n=%d Y=%.0f..%.0f grade<=%.2f%% side=%s X=%.0f..%.0f Z=%.0f..%.0f"):format(
				base,
				#parts,
				minY,
				maxY,
				maxGrade,
				side,
				minX,
				maxX,
				minZ,
				maxZ
			)
		)
	end
end

-- Structural collision test: does any ramp deck part overlap a pier/mast?
local structural = {}
for _, d in ipairs(map:GetDescendants()) do
	if d:IsA("BasePart") then
		local nm = d.Name
		if nm:find("PierColumn") or nm:find("PAMast") or nm:find("GirderRib") then
			table.insert(structural, d)
		end
	end
end
table.insert(out, "structuralParts=" .. #structural)

local hits = 0
local detail = {}
for _, base in ipairs(order) do
	local parts = runs[base] or {}
	local h = 0
	for _, p in ipairs(parts) do
		for _, s in ipairs(structural) do
			local dx = math.abs(p.Position.X - s.Position.X)
			local dz = math.abs(p.Position.Z - s.Position.Z)
			local dy = math.abs(p.Position.Y - s.Position.Y)
			local rx = (p.Size.X + s.Size.X) / 2
			local rz = (p.Size.Z + s.Size.Z) / 2
			local ry = (p.Size.Y + s.Size.Y) / 2
			if dx < rx and dz < rz and dy < ry then
				h += 1
			end
		end
	end
	hits += h
	table.insert(detail, base .. "=" .. h)
end
table.insert(out, "STRUCTURAL_HITS total=" .. hits .. " (" .. table.concat(detail, " ") .. ")")
return table.concat(out, "\n")