server/block: Implement brewing stand (#916)

Co-authored-by: TwistedAsylumMC <[email protected]>
Co-authored-by: DaPigGuy <[email protected]>

server/block/brewer.go

@@ -0,0 +1,253 @@
+package block
+
+import (
+	"github.com/df-mc/dragonfly/server/block/cube"
+	"github.com/df-mc/dragonfly/server/item"
+	"github.com/df-mc/dragonfly/server/item/inventory"
+	"github.com/df-mc/dragonfly/server/item/recipe"
+	"github.com/df-mc/dragonfly/server/world"
+	"github.com/df-mc/dragonfly/server/world/sound"
+	"sync"
+	"time"
+)
+
+// brewer is a struct that may be embedded by blocks that can brew potions, such as brewing stands.
+type brewer struct {
+	mu sync.Mutex
+
+	viewers   map[ContainerViewer]struct{}
+	inventory *inventory.Inventory
+
+	duration   time.Duration
+	fuelAmount int32
+	fuelTotal  int32
+}
+
+// newBrewer creates a new initialised brewer. The inventory is properly initialised.
+func newBrewer() *brewer {
+	b := &brewer{viewers: make(map[ContainerViewer]struct{})}
+	b.inventory = inventory.New(5, func(slot int, _, item item.Stack) {
+		b.mu.Lock()
+		defer b.mu.Unlock()
+		for viewer := range b.viewers {
+			viewer.ViewSlotChange(slot, item)
+		}
+	})
+	return b
+}
+
+// InsertItem ...
+func (b *brewer) InsertItem(h Hopper, pos cube.Pos, w *world.World) bool {
+	for sourceSlot, sourceStack := range h.inventory.Slots() {
+		var slot int
+
+		if sourceStack.Empty() {
+			continue
+		}
+
+		if h.Facing == cube.FaceDown {
+			if !recipe.ValidBrewingReagent(sourceStack.Item()) {
+				// This item is not a valid brewing reagent.
+				continue
+			}
+			slot = 0
+		} else if _, ok := sourceStack.Item().(item.BlazePowder); ok {
+			slot = 4
+		} else {
+			_, okPotion := sourceStack.Item().(item.Potion)
+			_, okSplash := sourceStack.Item().(item.SplashPotion)
+			_, okLingering := sourceStack.Item().(item.LingeringPotion)
+			_, okBottle := sourceStack.Item().(item.GlassBottle)
+			if !okPotion && !okSplash && !okLingering && !okBottle {
+				continue
+			}
+			for brewingSlot, brewingStack := range b.inventory.Slots() {
+				if brewingSlot == 0 || brewingSlot == 4 {
+					continue
+				}
+				if brewingStack.Count() == brewingStack.MaxCount() || !brewingStack.Comparable(sourceStack) {
+					continue
+				}
+
+				slot = brewingSlot
+				break
+			}
+			// Could not find an empty slot
+			if slot == 0 {
+				continue
+			}
+		}
+
+		stack := sourceStack.Grow(-sourceStack.Count() + 1)
+		it, _ := b.Inventory(w, pos).Item(slot)
+
+		if !sourceStack.Comparable(it) {
+			// The items are not the same.
+			continue
+		}
+		if it.Count() == it.MaxCount() {
+			// The item has the maximum count that the stack is able to hold.
+			continue
+		}
+		if !it.Empty() {
+			stack = it.Grow(1)
+		}
+
+		_ = b.Inventory(w, pos).SetItem(slot, stack)
+		_ = h.inventory.SetItem(sourceSlot, sourceStack.Grow(-1))
+		return true
+
+	}
+	return false
+}
+
+// ExtractItem ...
+func (b *brewer) ExtractItem(h Hopper, pos cube.Pos, w *world.World) bool {
+	for sourceSlot, sourceStack := range b.inventory.Slots() {
+		if sourceStack.Empty() {
+			continue
+		}
+
+		if sourceSlot == 0 || sourceSlot == 4 {
+			continue
+		}
+
+		_, err := h.inventory.AddItem(sourceStack.Grow(-sourceStack.Count() + 1))
+		if err != nil {
+			// The hopper is full.
+			continue
+		}
+
+		_ = b.Inventory(w, pos).SetItem(sourceSlot, sourceStack.Grow(-1))
+		return true
+	}
+	return false
+}
+
+// Duration returns the remaining duration of the brewing process.
+func (b *brewer) Duration() time.Duration {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	return b.duration
+}
+
+// Fuel returns the fuel and maximum fuel of the brewer.
+func (b *brewer) Fuel() (fuel, maxFuel int32) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	return b.fuelAmount, b.fuelTotal
+}
+
+// Inventory returns the inventory of the brewer.
+func (b *brewer) Inventory(*world.World, cube.Pos) *inventory.Inventory {
+	return b.inventory
+}
+
+// AddViewer adds a viewer to the brewer, so that it is updated whenever the inventory of the brewer is changed.
+func (b *brewer) AddViewer(v ContainerViewer, _ *world.World, _ cube.Pos) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	b.viewers[v] = struct{}{}
+}
+
+// RemoveViewer removes a viewer from the brewer, so that slot updates in the inventory are no longer sent to
+// it.
+func (b *brewer) RemoveViewer(v ContainerViewer, _ *world.World, _ cube.Pos) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	delete(b.viewers, v)
+}
+
+// setDuration sets the brew duration of the brewer to the given duration.
+func (b *brewer) setDuration(duration time.Duration) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	b.duration = duration
+}
+
+// setFuel sets the fuel of the brewer to the given fuel and maximum fuel.
+func (b *brewer) setFuel(fuel, maxFuel int32) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	b.fuelAmount, b.fuelTotal = fuel, maxFuel
+}
+
+// tickBrewing ticks the brewer, ensuring the necessary items exist in the brewer, and then processing all inputted
+// items for the necessary duration.
+func (b *brewer) tickBrewing(block string, pos cube.Pos, w *world.World) {
+	b.mu.Lock()
+
+	// Get each item in the brewer. We don't need to validate errors here since we know the bounds of the brewer.
+	left, _ := b.inventory.Item(1)
+	middle, _ := b.inventory.Item(2)
+	right, _ := b.inventory.Item(3)
+
+	// Keep track of our past durations, since if any of them change, we need to be able to tell they did and then
+	// update the viewers on the change.
+	prevDuration := b.duration
+	prevFuelAmount := b.fuelAmount
+	prevFuelTotal := b.fuelTotal
+
+	// If we need fuel, try and burn some.
+	fuel, _ := b.inventory.Item(4)
+
+	if _, ok := fuel.Item().(item.BlazePowder); ok && b.fuelAmount <= 0 {
+		defer b.inventory.SetItem(4, fuel.Grow(-1))
+		b.fuelAmount, b.fuelTotal = 20, 20
+	}
+
+	// Now get the ingredient item.
+	ingredient, _ := b.inventory.Item(0)
+
+	// Check each input and see if it is affected by the ingredient.
+	leftOutput, leftAffected := recipe.Perform(block, left.Item(), ingredient.Item())
+	middleOutput, middleAffected := recipe.Perform(block, middle.Item(), ingredient.Item())
+	rightOutput, rightAffected := recipe.Perform(block, right.Item(), ingredient.Item())
+
+	// Ensure that we have enough fuel to continue.
+	if b.fuelAmount > 0 {
+		// Now make sure that we have at least one potion that is affected by the ingredient.
+		if leftAffected || middleAffected || rightAffected {
+			// Tick our duration. If we have no brew duration, set it to the default of twenty seconds.
+			if b.duration == 0 {
+				b.duration = time.Second * 20
+			}
+			b.duration -= time.Millisecond * 50
+
+			// If we have no duration, we are done.
+			if b.duration <= 0 {
+				// Create the output items.
+				if leftAffected {
+					defer b.inventory.SetItem(1, leftOutput[0])
+				}
+				if middleAffected {
+					defer b.inventory.SetItem(2, middleOutput[0])
+				}
+				if rightAffected {
+					defer b.inventory.SetItem(3, rightOutput[0])
+				}
+
+				// Reduce the ingredient by one.
+				defer b.inventory.SetItem(0, ingredient.Grow(-1))
+				w.PlaySound(pos.Vec3Centre(), sound.PotionBrewed{})
+
+				// Decrement the fuel, and reset the duration.
+				b.fuelAmount--
+				b.duration = 0
+			}
+		} else {
+			// None of the potions are affected by the ingredient, so reset the duration.
+			b.duration = 0
+		}
+	} else {
+		// We don't have enough fuel, so reset our progress.
+		b.duration, b.fuelAmount, b.fuelTotal = 0, 0, 0
+	}
+
+	// Update the viewers on the new durations.
+	for v := range b.viewers {
+		v.ViewBrewingUpdate(prevDuration, b.duration, prevFuelAmount, b.fuelAmount, prevFuelTotal, b.fuelTotal)
+	}
+
+	b.mu.Unlock()
+}