using System.Collections.Generic;

namespace Sunless.Architecture;

// The routing filed as named pieces: the legs come out of the stair engine, the landings out of the platform
// engine and the rails out of the barrier engine, so nothing about a tread, a slab or a baluster lives here.
public static class ArchExteriorStairGen {
	public static void Build(
		ArchMesh canvas,
		ArchExteriorStairPart part,
		ArchBuilding building,
		ArchPlan plan,
		ArchKit kit,
		ArchStyle style,
		List<ArchDoorRequest> doors ) {
		var shape = ArchExteriorStair.Resolve( part, building, kit );

		if ( !shape.IsUsable ) {
			return;
		}

		using ( canvas.Part( ArchPieces.Flight ) ) {
			foreach ( var flight in shape.Flights ) {
				ArchStairGen.Build( canvas, flight.Stair, shape.Host, building, kit, style, doors, plan );
			}
		}

		using ( canvas.Part( ArchPieces.Landings ) ) {
			foreach ( var landing in shape.Landings ) {
				ArchPlatformGen.Build( canvas, ArchExteriorStair.Slab( part, landing ), building, plan, kit, style );
			}
		}

		if ( !part.Rail ) {
			return;
		}

		using ( canvas.Part( ArchPieces.Rails ) ) {
			Rails( canvas, shape, kit, ArchBarrierBrushes.Of( style, part.Palette, building.Palette ) );
		}
	}

	// Follow on the rake, Level on a landing: the same engine, told which of the two the ground under it does.
	static void Rails( ArchMesh canvas, ArchExteriorStairShape shape, ArchKit kit, ArchBarrierBrushes brushes ) {
		foreach ( var flight in shape.Flights ) {
			ArchFixtureGuard.Build( canvas, flight.Edge, kit, kit.HandrailHeight, BarrierGround.Follow, brushes );
		}

		foreach ( var landing in shape.Landings ) {
			ArchFixtureGuard.Build( canvas, landing.Edge, kit, kit.HandrailHeight, BarrierGround.Level, brushes );
		}
	}
}