class_name Wall extends Node2D
## Wall entity — built by a pawn with a Build job. Blocks pathfinding once
## complete. Rendered as a bottom-anchored tall sprite (Y-sorted) so it
## occludes pawns standing behind it, matching the project's 3/4-perspective
## rendering pivot (see memory.md Decisions: "Wall layer rendering").
##
## Build model (docs/implementation.md Phase 5):
##   A ConstructionProvider creates a Job whose BUILD toil calls on_build_tick()
##   once per sim tick via JobRunner. After BUILD_TICKS ticks the wall is
##   complete: it stamps the data-layer TileMap (World.mark_wall_tile), blocks
##   pathfinding, and transitions from ghost (40% alpha) to solid rendering.
##
## Material support:
##   Phase 5 ships stone only. Wood constant is defined for Phase 6+ wiring
##   (Pixel Crawler Walls.png asset crop session) without breaking the data model.
##
## World registration: World.register_build_site / World.unregister_build_site
## are called from _ready / _exit_tree. The actual World methods land in the
## Opus integration pass.

const TILE_SIZE_PX: int = 16

## Sim ticks to complete construction at 1× speed (100 ticks = 5 sim seconds).
const BUILD_TICKS: int = 100

## Supported materials. Phase 5 uses MATERIAL_STONE; MATERIAL_WOOD is reserved
## for the Phase 6+ art-authoring pass.
const MATERIAL_STONE: StringName = &"stone"
const MATERIAL_WOOD: StringName = &"wood"

# ── state ──────────────────────────────────────────────────────────────────────

@export var wall_material: StringName = MATERIAL_STONE
@export var tile: Vector2i = Vector2i.ZERO

## 0..BUILD_TICKS. Advanced by on_build_tick(). Entity is in "ghost" state
## until build_progress reaches BUILD_TICKS.
var build_progress: int = 0
var _completed: bool = false


# ── lifecycle ──────────────────────────────────────────────────────────────────

func _ready() -> void:
	World.register_build_site(self)


func _exit_tree() -> void:
	World.unregister_build_site(self)


# ── public API ─────────────────────────────────────────────────────────────────

## One-shot initialiser. Call after add_child() so _ready() has already fired.
func setup(p_tile: Vector2i, p_material: StringName) -> void:
	tile = p_tile
	wall_material = p_material
	# Bottom-anchor the sprite: position.y sits at the bottom of the tile so the
	# 16×32 virtual sprite "rises" into the cell above. Y-sort uses position.y.
	position = Vector2(
		tile.x * TILE_SIZE_PX + TILE_SIZE_PX / 2.0,
		tile.y * TILE_SIZE_PX + TILE_SIZE_PX
	)
	queue_redraw()
	Audit.log("wall", "%s wall ghost placed at %s" % [wall_material, tile])


## True while the wall still needs construction work.
## JobRunner's _tick_build checks this to decide when the toil is done.
func is_buildable() -> bool:
	return not _completed


## Human-readable label for job descriptions and Audit logs.
func label() -> String:
	return "%s wall" % wall_material


## Called by the BUILD toil in JobRunner once per sim tick while the pawn works.
## Advances build_progress and completes the wall when BUILD_TICKS is reached.
func on_build_tick() -> void:
	if _completed:
		return
	build_progress += 1
	queue_redraw()
	if build_progress >= BUILD_TICKS:
		_complete()


## True once the wall has been fully built.
func is_completed() -> bool:
	return _completed


# ── save / load ────────────────────────────────────────────────────────────────

func to_dict() -> Dictionary:
	return {
		"tile_x": tile.x,
		"tile_y": tile.y,
		"material": str(wall_material),
		"build_progress": build_progress,
		"completed": _completed,
	}


static func from_dict(d: Dictionary) -> Dictionary:
	return {
		"tile_x": int(d.get("tile_x", 0)),
		"tile_y": int(d.get("tile_y", 0)),
		"material": str(d.get("material", "stone")),
		"build_progress": int(d.get("build_progress", 0)),
		"completed": bool(d.get("completed", false)),
	}


# ── render ─────────────────────────────────────────────────────────────────────

func _draw() -> void:
	# Wall is drawn as a bottom-anchored 16×32 rect occupying the lower portion
	# of the virtual sprite area. The origin (0, 0) of _draw() sits at position,
	# which is at the tile's bottom-centre (tile_y * 16 + 16).
	# Drawing upward: Y goes from 0 to -32 in local space.
	var alpha: float = 1.0 if _completed else 0.4

	if wall_material == MATERIAL_STONE:
		_draw_stone_wall(alpha)
	else:
		# Fallback: render as wood until art assets are wired in Phase 6+.
		_draw_wood_wall(alpha)


func _draw_stone_wall(alpha: float) -> void:
	var base := Color(0.55, 0.55, 0.50, alpha)
	var mortar := Color(0.40, 0.40, 0.38, alpha)

	# Main body: 16 px wide, 32 px tall, origin at bottom-centre.
	draw_rect(Rect2(Vector2(-8.0, -32.0), Vector2(16.0, 32.0)), base)

	# Mortar / horizontal stone-course lines (4 lines spaced 8 px apart).
	for i in range(1, 5):
		var y: float = -8.0 * float(i)
		draw_line(Vector2(-8.0, y), Vector2(8.0, y), mortar, 1.0)

	# Outline.
	draw_rect(Rect2(Vector2(-8.0, -32.0), Vector2(16.0, 32.0)), Color(0.0, 0.0, 0.0, 0.5 * alpha), false, 1.0)


func _draw_wood_wall(alpha: float) -> void:
	var base := Color(0.55, 0.40, 0.22, alpha)
	var plank := Color(0.45, 0.32, 0.16, alpha)

	draw_rect(Rect2(Vector2(-8.0, -32.0), Vector2(16.0, 32.0)), base)

	# Vertical plank lines.
	for x_offset in [-3.0, 2.0]:
		draw_line(
			Vector2(x_offset, -32.0),
			Vector2(x_offset, 0.0),
			plank, 1.0
		)

	draw_rect(Rect2(Vector2(-8.0, -32.0), Vector2(16.0, 32.0)), Color(0.0, 0.0, 0.0, 0.5 * alpha), false, 1.0)


# ── internal ───────────────────────────────────────────────────────────────────

func _complete() -> void:
	_completed = true

	# Block pathfinding — wall is now impassable.
	if World.pathfinder != null:
		World.pathfinder.set_cell_walkable(tile, false)

	# Stamp the data-layer TileMap so room / roof / save logic sees the wall.
	World.mark_wall_tile(tile, wall_material)

	queue_redraw()
	Audit.log("wall", "%s wall completed at %s" % [wall_material, tile])