Vendor

NPC vendor management system with editing and rarity support for the Lilia framework.

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Overview

The vendor library provides comprehensive functionality for managing NPC vendors in the Lilia framework. It handles vendor configuration, editing, presets, and rarity systems for items sold by vendors. The library operates on both server and client sides, with the server handling vendor data processing and the client managing the editing interface. It includes support for vendor presets, item rarities, stock management, pricing, faction/class restrictions, and visual customization. The library ensures that vendors can be easily configured and managed through both code and in-game editing tools.

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lia.vendor.addPreset(name, items)

Purpose

Register a reusable vendor item preset with validated entries.

When Called

During initialization to define canned loadouts for vendors (e.g., weapon dealer, medic).

Parameters

string name Unique preset name.

table items Map of item uniqueIDs to tables with pricing/stock metadata.

Example Usage

  -- Define a preset and apply it dynamically based on map location.
  lia.vendor.addPreset("gunsmith", {
      ar15 = {stock = 3, price = 3500},
      akm = {stock = 2, price = 3200},
      ["9mm"] = {stock = 50, price = 30}
  })
  hook.Add("OnVendorSpawned", "SetupMapVendors", function(vendorEnt)
      if vendorEnt:GetClass() ~= "lia_vendor" then return end
      local zone = lia.zones and lia.zones.getNameAtPos(vendorEnt:GetPos()) or "default"
      if zone == "Armory" then
          vendorEnt:applyPreset("gunsmith")
          vendorEnt:setFactionAllowed(FACTION_POLICE, true)
      end
  end)

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lia.vendor.getPreset(name)

Purpose

Retrieve a preset definition by name.

When Called

While applying presets to vendors or inspecting available vendor templates.

Parameters

string name Preset identifier (case-insensitive).

Returns

table|nil Item definition table if present.

Example Usage

  -- Clone and tweak a preset before applying to a specific vendor.
  local preset = table.Copy(lia.vendor.getPreset("gunsmith") or {})
  if preset then
      preset["9mm"].price = 25
      preset["akm"] = nil -- remove AKM for this vendor
      vendor:applyPreset("gunsmith") -- base preset
      for item, data in pairs(preset) do
          vendor:setItemPrice(item, data.price)
          if data.stock then vendor:setMaxStock(item, data.stock) end
      end
  end

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lia.vendor.getVendorProperty(entity, property)

Purpose

Fetch a vendor property from cache with default fallback.

When Called

Anywhere vendor state is read (pricing, stock, model, etc.).

Parameters

Entity entity Vendor NPC entity.

string property Property key from `lia.vendor.defaults`.

Returns

any Cached property value or default.

Example Usage

  -- Build a UI row with live vendor state (including defaults).
  local function addVendorRow(list, vendorEnt)
      local name = lia.vendor.getVendorProperty(vendorEnt, "name")
      local cash = lia.vendor.getVendorProperty(vendorEnt, "money") or 0
      local items = lia.vendor.getVendorProperty(vendorEnt, "items")
      list:AddLine(name, cash, table.Count(items or {}))
  end

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lia.vendor.setVendorProperty(entity, property, value)

Purpose

Mutate a vendor property, pruning defaults to keep network/state lean.

When Called

During vendor edits (net messages) or when scripting dynamic vendor behavior.

Parameters

Entity entity Vendor NPC entity.

string property Key to update.

any value New value to store; default-equivalent values clear the entry.

Example Usage

  -- Dynamically flip vendor inventory for an event and prune defaults.
  hook.Add("EventStarted", "StockEventVendors", function()
      for _, vendorEnt in ipairs(ents.FindByClass("lia_vendor")) do
          lia.vendor.setVendorProperty(vendorEnt, "items", {
              ["event_ticket"] = {stock = 100, price = 0},
              ["rare_crate"] = {stock = 5, price = 7500}
          })
      end
  end)

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lia.vendor.syncVendorProperty(entity, property, value, isDefault)

Purpose

Broadcast a vendor property update to all clients.

When Called

Server-side after mutating vendor properties to keep clients in sync.

Parameters

Entity entity Vendor NPC entity.

string property Key being synchronized.

any value New value for the property.

boolean isDefault Whether the property should be cleared (uses defaults clientside).

Example Usage

  -- Force sync after a server-side rebuild of vendor data.
  local function rebuildVendor(vendorEnt)
      lia.vendor.setVendorProperty(vendorEnt, "name", "Quartermaster")
      lia.vendor.setVendorProperty(vendorEnt, "factionSellScales", { [FACTION_POLICE] = 0.8 })
      lia.vendor.syncVendorProperty(vendorEnt, "name", "Quartermaster", false)
      lia.vendor.syncVendorProperty(vendorEnt, "factionSellScales", { [FACTION_POLICE] = 0.8 }, false)
  end

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lia.vendor.getAllVendorData(entity)

Purpose

Build a full vendor state table with defaults applied.

When Called

Before serializing vendor data for saving or sending to clients.

Parameters

Entity entity Vendor NPC entity.

Returns

table Key-value table covering every defaulted vendor property.

Example Usage

  -- Serialize full vendor state for a persistence layer.
  net.Receive("RequestVendorSnapshot", function(_, ply)
      local ent = net.ReadEntity()
      local data = lia.vendor.getAllVendorData(ent)
      if not data then return end
      lia.data.set("vendor_" .. ent:EntIndex(), data)
      net.Start("SendVendorSnapshot")
      net.WriteTable(data)
      net.Send(ply)
  end)

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