生命周期与事件

Item{
    id = "Berries",
    events = {
        onUse = function(item, ctx)
            Item.get("Wood"):give(1)      -- eat a berry, get a log
        end,
    },
}

local event = require("palforge.core.event")

event.on("pal.spawned", function(ctx) print(ctx.actor) end)
event.emit("example:custom", { note = "channels are created on demand" })

event.CHANNELS   --> {
--   "gameStart",
--   "world.ready", "world.left",
--   "building.place", "building.load", "building.interact", "building.remove",
--   "building.build",
--   "pal.spawned", "pal.damaged", "pal.death", "pal.captured",
--   "item.obtain", "item.use", "item.craft", "item.discard",
--   "skill.activate", "skill.hit", "skill.equip", "skill.unequip",
--   "tick",
-- }

local event = require("palforge.core.event")

event.on("mypack:quest.completed", function(ctx)
    Item.get("Wood"):give(ctx.reward or 1)
end)

event.emit("mypack:quest.completed", { reward = 25 })

event.on("tick", function(ctx)
    -- ctx.count = how many heartbeats since the loop started
    -- ctx.now   = os.clock() at emit time
end)

local event = require("palforge.core.event")
local log   = require("palforge.utils.log").scope("beat")

local sub = event.every(5000, function()
    log.info("five seconds of heartbeats")
end)

sub:unsubscribe()   -- stop it

local event = require("palforge.core.event")
local log   = require("palforge.utils.log").scope("lamp")

Building{
    id     = "example:Lamp",
    name   = "Signal Lamp",
    gridCm = 100,
    state  = { loads = 0 },
    mesh   = {
        kind  = "static",
        model = "/Game/Pal/Model/Prop/Architecture/WorkBenchPrimitive/SM_WorkBenchPrimitive.SM_WorkBenchPrimitive",
    },
    events = {
        onWorldReady = function(inst, ctx)
            -- once per world load, on every lamp the first scan tracked
            inst.state.loads = (inst.state.loads or 0) + 1
            inst:save()
            log.info(inst.key .. " online, load #" .. tostring(inst.state.loads))
        end,
        onRightClick = function(inst, ctx)
            log.info(inst.key .. " has survived " .. tostring(inst.state.loads) .. " loads")
        end,
    },
}

-- the same moment, as a cross-cutting subscriber
event.on("world.ready", function()
    log.info(tostring(#event.instances()) .. " structures tracked")
end)

local log = require("palforge.utils.log").scope("rations")

Item{
    id       = "example:Ration",
    name     = "Field Ration",
    category = "consumable",
    maxStack = 20,
    events = {
        onObtain = function(item, ctx)
            log.info("picked up " .. tostring(ctx.count) .. " x " .. tostring(ctx.itemId))
        end,
        onUse = function(item, ctx)
            -- ctx.itemId is "example_Ration" here: the row name, not the colon form
            Item.get("Berries"):give(1)
        end,
    },
}

local log = require("palforge.utils.log").scope("fireball")

local Fireball = Skill{
    id       = "example:Fireball",
    kind     = "active",
    element  = "fire",
    cooldown = 3.0,
    power    = 50,
    events = {
        onActivate = function(skill, owner, ctx)
            log.info(skill.id .. " fired by " .. tostring(owner))
        end,
    },
}

Fireball:activate(myPalActor)   -- false while cooling down
Fireball:hit(targetActor)

local log = require("palforge.utils.log").scope("handlers")

Pal{
    id = "ChickenPal",
    events = {
        onSpawned = function(pal, ctx)          -- pal is the Pal.Handle
            pal:renderOn(ctx.actor)
        end,
    },
}

Item{
    id = "Berries",
    events = {
        onUse = function(item, ctx)             -- item is the Item.Handle
            log.info(item.id .. " used as " .. tostring(ctx.itemId))
        end,
    },
}

Building{
    id = "example:Bench",
    events = {
        onRightClick = function(inst, ctx)      -- inst is the LIVE instance
            inst.state.uses = (inst.state.uses or 0) + 1
            inst:save()
        end,
    },
}

Skill{
    id = "example:Fireball",
    events = {
        onActivate = function(skill, owner, ctx) end,   -- owner comes before ctx
    },
}

Effect{
    id = "example:Regen",
    events = {
        onTick = function(effect, target, ctx) end,     -- target comes before ctx
    },
}

[PalForge.event][err] item.use -> onUse handler failed: content/rations.lua:12: attempt to index a nil value
[PalForge.event][err] world.ready -> onWorldReady handler failed on 'example_Lamp@12,-8,3': ...

local log = require("palforge.utils.log").scope("counter")

Building{
    id     = "example:Counter",
    name   = "Counter Bench",
    gridCm = 100,
    state  = { uses = 0 },
    mesh   = {
        kind  = "static",
        model = "/Game/Pal/Model/Prop/Architecture/WorkBenchPrimitive/SM_WorkBenchPrimitive.SM_WorkBenchPrimitive",
    },
    events = {
        onPlace = function(inst, ctx)
            log.info("placed at " .. inst.key .. " by " .. tostring(ctx.player))
            inst.state.uses = 0
            inst:save()
        end,
        onLoad = function(inst, ctx)
            if ctx.reconstructed then
                log.info("restored with " .. tostring(inst.state.uses) .. " uses")
            end
        end,
        onRightClick = function(inst, ctx)
            inst.state.uses = inst.state.uses + 1
            inst:save()
        end,
        onRemove = function(inst, ctx)
            log.info("removed, reason " .. tostring(ctx.reason))
        end,
    },
}

Building{
    id           = "example:SlowFurnace",
    tickInterval = 20,          -- once every 20 heartbeats, about 10 seconds
    state        = { fuel = 0 },
    events = {
        onTick = function(inst, ctx)
            if inst.state.fuel > 0 then
                inst.state.fuel = inst.state.fuel - 1
                inst:setDirty()
            end
        end,
    },
}

local event = require("palforge.core.event")

event.instances()                       -- every live instance in the world
event.instances("example:Counter")      -- filtered by definition id or matched build id
event.instanceOfActor(someActor)        -- the instance bound to an actor, or nil
event.isWorldReady()                    -- is the building runtime allowed to touch objects

Building.get("example:Counter"):instances()   -- the same list, from the handle

local log = require("palforge.utils.log").scope("regen")

local Regen = Effect{
    id          = "example:Regen",
    name        = "Regeneration",
    description = "heals a little every second",
    duration    = 10.0,       -- omit for an effect that runs until :remove()
    interval    = 1.0,        -- omit for no periodic tick
    stackable   = true,
    maxStacks   = 3,
    events = {
        onApply = function(effect, target, ctx)
            log.info("regen on " .. tostring(target) .. " stacks=" .. ctx.stacks)
        end,
        onTick = function(effect, target, ctx)
            -- ctx.elapsed = seconds since apply, ctx.stacks = current stack count
            log.info("regen tick at " .. tostring(ctx.elapsed))
        end,
        onStack = function(effect, target, ctx)
            log.info("regen refreshed, stacks=" .. ctx.stacks)
        end,
        onExpire = function(effect, target, ctx)
            log.info("regen over, reason " .. tostring(ctx.reason))
        end,
    },
}

local me = Player.character()
Regen:apply(me)
Regen:apply(me)              -- onStack, stacks = 2, timer back to 10 s

Regen:isActive(me)           -- true
Regen:stacksOn(me)           -- 2
Regen:timeLeft(me)           -- seconds left, nil when the effect has no duration
Effect.activeOn(me)          -- { "example:Regen" }

Regen:remove(me)             -- onExpire with reason "removed"

local event = require("palforge.core.event")
local log   = require("palforge.utils.log").scope("bus")

-- one-liner
event.on("world.ready", function()
    log.info("world is up")
end)

-- keep the handle and stop later
local sub = event.on("item.obtain", function(ctx)
    log.info("got " .. tostring(ctx.count) .. " x " .. tostring(ctx.itemId))
end)

sub:unsubscribe()

local event = require("palforge.core.event")
local log   = require("palforge.utils.log").scope("chain")

-- only the workbench, and only the id
local sub = event.observable("building.interact")
    :filter(function(ctx) return ctx and ctx.buildId == "WorkBench" end)
    :map(function(ctx) return ctx.player end)
    :subscribe(function(player)
        log.info("workbench used by " .. tostring(player))
    end)

-- a countdown that stops itself
event.observable("tick")
    :filter(function(ctx) return ctx.count % 10 == 0 end)
    :take(3)
    :subscribe(function(ctx)
        log.info("beat " .. tostring(ctx.count))
    end)

sub:unsubscribe()

local event = require("palforge.core.event")
local log   = require("palforge.utils.log").scope("trace")

for _, name in ipairs(event.CHANNELS) do
    if name ~= "tick" then
        event.on(name, function(ctx)
            local bits = {}
            if type(ctx) == "table" then
                for _, k in ipairs({ "buildId", "itemId", "count", "key", "reason" }) do
                    if ctx[k] ~= nil then bits[#bits + 1] = k .. "=" .. tostring(ctx[k]) end
                end
            end
            log.info(name .. " " .. table.concat(bits, " "))
        end)
    end
end

local log = require("palforge.utils.log").scope("generator")

Building{
    id           = "example:BerryBush",
    name         = "Berry Bush",
    gridCm       = 100,
    tickInterval = 40,                 -- about 20 seconds
    state        = { grown = 0 },
    mesh = {
        kind  = "static",
        model = "/Game/Pal/Model/Prop/Architecture/WorkBenchPrimitive/SM_WorkBenchPrimitive.SM_WorkBenchPrimitive",
    },
    events = {
        onPlace = function(inst, ctx)
            inst.state.grown = 0
            inst:save()
        end,

        onLoad = function(inst, ctx)
            log.info(string.format("bush %s ready, grown=%d, fromSave=%s",
                inst.key, inst.state.grown or 0, tostring(ctx.reconstructed)))
        end,

        onTick = function(inst, ctx)
            inst.state.grown = (inst.state.grown or 0) + 1
            inst:setDirty()            -- cheap; the next :save flushes it
        end,

        onRightClick = function(inst, ctx)
            local n = inst.state.grown or 0
            if n <= 0 then return end
            Item.get("Berries"):give(n)
            inst.state.grown = 0
            inst:save()                -- harvesting is worth a disk write
        end,

        onRemove = function(inst, ctx)
            log.info("bush " .. inst.key .. " gone, reason " .. tostring(ctx.reason))
        end,
    },
}

local log = require("palforge.utils.log").scope("ember")

local Burning = Effect{
    id        = "example:Burning",
    name      = "Burning",
    duration  = 6.0,
    interval  = 1.0,
    stackable = true,
    maxStacks = 3,
    events = {
        onTick = function(effect, target, ctx)
            log.info("burning " .. tostring(target) .. " stacks=" .. tostring(ctx.stacks))
        end,
        onExpire = function(effect, target, ctx)
            log.info("burning ended, reason " .. tostring(ctx.reason))
        end,
    },
}

Pal{
    id          = "ChickenPal",
    name        = "Ember Chicken",
    description = "a chicken with a temper",
    mesh = Mesh{
        id    = "example:EmberChicken",
        model = "/Game/Pal/Model/Character/Monster/ChickenPal/SK_ChickenPal.SK_ChickenPal",
    },
    color = { r = 1.0, g = 0.4, b = 0.2, a = 1.0 },
    events = {
        onSpawned = function(pal, ctx)
            pal:renderOn(ctx.actor)                 -- already done for you; the guard makes this free
        end,
        onDamaged = function(pal, ctx)
            Burning:apply(ctx.actor)                -- re-apply stacks and refreshes
        end,
        onDeath = function(pal, ctx)
            Burning:remove(ctx.actor)
            Item.get("Wood"):give(3)
        end,
        onCaptured = function(pal, ctx)
            log.info(pal:name() .. " captured")
        end,
    },
}

local uobject = require("palforge.core.uobject")
local log     = require("palforge.utils.log").scope("patrol")

local seen = {}     -- GetFullName string -> seconds watched

Pal{
    id = "SheepBall",
    events = {
        onSpawned = function(pal, ctx)
            local k = uobject.key(ctx.actor)
            if k then seen[k] = 0 end
        end,
        onTick = function(pal, ctx)
            local k = uobject.key(ctx.actor)
            if not k then return end                 -- a pawn that will not answer its name
            seen[k] = (seen[k] or 0) + 3             -- PAL_SCAN_MS, in seconds
            log.info("sheepball " .. k .. " watched for " .. tostring(seen[k]) .. " s")
        end,
        onDeath = function(pal, ctx)
            local k = uobject.key(ctx.actor)
            if k then seen[k] = nil end
        end,
    },
}

local log = require("palforge.utils.log").scope("turret")

local Zap = Skill{
    id       = "example:Zap",
    kind     = "active",
    element  = "electric",
    cooldown = 2.0,
    power    = 25,
    events = {
        onActivate = function(skill, owner, ctx)
            log.info("zap from " .. tostring(ctx.key))
        end,
    },
}

Building{
    id     = "example:Turret",
    name   = "Zap Turret",
    state  = { shots = 0 },
    events = {
        onRightClick = function(inst, ctx)
            if Zap:activate(inst.actor, { key = inst.key }) then
                inst.state.shots = (inst.state.shots or 0) + 1
                inst:save()
            else
                log.info("still cooling down, " .. tostring(Zap:cooldownLeft(inst.actor)) .. " s left")
            end
        end,
    },
}

local event = require("palforge.core.event")

event.on("world.left", function()
    for _, inst in ipairs(event.instances()) do
        pcall(function() inst:setDirty() end)
    end
end)