Package Chat as feature resulting in better abstraction

README.md

@@ -4,7 +4,7 @@ A developer-friendly Lua interface for working with multiple generative AI provi
 
 ## Providers
 
-> ⚠️ This is a work in progress so any help is appreciated!
+> ⚠️ This is a work in progress so any help is highly appreciated!
 
 - [OpenAI](https://platform.openai.com/docs/overview)
 
@@ -23,19 +23,41 @@ A developer-friendly Lua interface for working with multiple generative AI provi
 
 ```lua
 local AI = require("src.ai")
-local Chat = require("src.chat")
 
-local api_key = "<YOUR_API_KEY>"
-local endpoint = "https://api.openai.com/v1/chat/completions"
-local model = "gpt-4o-mini"
-local system_prompt = "You are Torben, the king of a nation."
-local settings = { stream = true }
+local client = AI.new("<YOUR_API_KEY>", "https://api.openai.com/v1/chat/completions")
+```
+
+### Minimal
+
+```lua
+local chat = client:chat("gpt-4o-mini")
+print(chat:say("Hello, world!"))
+```
 
-local ai = AI.new(api_key, endpoint)
-local chat = Chat.new(ai, model, system_prompt, settings)
+### Streaming
 
-local reply = chat:say("Give three short words of advice to the hero.")
-if not chat.settings.stream then print(reply) end
+```lua
+local chat = client:chat("gpt-4o-mini", { settings = { stream = true } })
+chat:say("Hello, world!")
+```
+
+### JSON
+
+```lua
+local npc_schema = {
+	name = { type = "string" },
+	class = { type = "string" },
+	level = { type = "integer" },
+}
+
+local json_object = {
+	title = "NPC",
+	description = "A non-player character's attributes.",
+	schema = npc_schema,
+}
+
+local chat = client:chat("gpt-4o-mini", { settings = { json = json_object } })
+print(chat:say("Create a powerful wizard called Torben."))
 ```
 
 See `main.lua` for a more detailed example.

main.lua

@@ -1,6 +1,5 @@
 local config = require("src.config")
 local AI = require("src.ai")
-local Chat = require("src.chat")
 
 local api_keys = config.api_keys
 
@@ -20,25 +19,21 @@ local structured_response_obj = {
 -- local api_key = api_keys.anthropic_api_key
 -- local endpoint = "https://api.anthropic.com/v1/messages"
 -- local model = "claude-3-5-sonnet-20241022"
--- local settings = {
--- 	stream = false,
--- 	json = structured_response_obj,
--- }
 
 local api_key = api_keys.openai_api_key
 local endpoint = "https://api.openai.com/v1/chat/completions"
 local model = "gpt-4o-mini"
-local settings = {
-	stream = false,
-	json = structured_response_obj,
-}
-
-local system_prompt = "Respond extremely briefly."
-
-local ai = AI.new(api_key, endpoint)
-local chat = Chat.new(ai, model, system_prompt, settings)
 
 local function main()
+	local client = AI.new(api_key, endpoint)
+	local chat = client:chat(model, {
+		system_prompt = "Respond extremely briefly.",
+		settings = {
+			stream = false,
+			json = structured_response_obj,
+		},
+	})
+
 	while true do
 		local user_prompt = "You are King Torben giving advice."
 		print(user_prompt)

src/ai.lua

@@ -1,6 +1,8 @@
 local config = require("src.config")
 local utils = require("src.utils")
-local providers = require("src.providers._load")
+local providers = require("src.providers")
+local features = require("src.features")
+
 local cjson = config.cjson
 
 ---Client for interacting with specified API endpoint
@@ -86,4 +88,14 @@ function AI:call(opts)
 	return reply, input_tokens, output_tokens
 end
 
+-- features:
+
+---Create chat instance with automatic tracking of messages and tokens
+---@param model string
+---@param opts table? Containing **settings** and or **system_prompt**
+---@return Chat
+function AI:chat(model, opts)
+	return features.Chat.new(self, model, opts)
+end
+
 return AI

src/features.lua

@@ -0,0 +1,6 @@
+---@module "src.features"
+local features = {}
+
+features.Chat = require("src.features.chat")
+
+return features

src/chat.lua → src/features/chat.lua

@@ -1,7 +1,7 @@
 local utils = require("src.utils")
 
 ---@class Chat Accumulating chat history and usage
----@field _ai table
+---@field ai table
 ---@field model string
 ---@field settings table?
 ---@field usage table
@@ -12,20 +12,19 @@ Chat.__index = Chat
 
 ---@param ai table
 ---@param model string
----@param system_prompt string?
----@param settings table?
-function Chat.new(ai, model, system_prompt, settings)
+---@param opts table? Containing **settings** and or **system_prompt**
+function Chat.new(ai, model, opts)
 	local self = setmetatable({}, Chat)
 
-	self._ai = ai
+	self.ai = ai
 	self.model = model
-	self.settings = settings or {}
+	self.settings = opts and opts.settings or {}
 	self.usage = { input = 0, output = 0 }
 	self.history = {}
-	self.system_prompt = system_prompt
+	self.system_prompt = opts and opts.system_prompt
 
 	-- insert system prompt into chat history at the start if provided
-	local system_message = self._ai.provider.construct_system_message(self.system_prompt)
+	local system_message = self.ai.provider.construct_system_message(self.system_prompt)
 	if system_message then -- some providers use system message as top-level arg
 		table.insert(self.history, system_message)
 	end
@@ -37,16 +36,18 @@ end
 ---@param user_prompt string
 ---@return string reply Full response text whether streamed or not
 function Chat:say(user_prompt)
-	table.insert(self.history, self._ai.provider.construct_user_message(user_prompt))
-	local reply, input_tokens, output_tokens = self._ai:call(self)
-	table.insert(self.history, self._ai.provider.construct_assistant_message(reply))
+	table.insert(self.history, self.ai.provider.construct_user_message(user_prompt))
+	local reply, input_tokens, output_tokens = self.ai:call(self)
+	table.insert(self.history, self.ai.provider.construct_assistant_message(reply))
 	self.usage.input = self.usage.input + input_tokens
 	self.usage.output = self.usage.output + output_tokens
 	return reply
 end
 
+---Caculate model pricing from input and output tokens in USD
+---@return number
 function Chat:get_cost()
-	return utils.calc_token_cost(self.model, self.usage, self._ai.provider.pricing)
+	return utils.calc_token_cost(self.model, self.usage, self.ai.provider.pricing)
 end
 
 return Chat

src/providers.lua

@@ -0,0 +1,7 @@
+---@module "src.providers"
+local providers = {}
+
+providers.openai = require("src.providers.openai")
+providers.anthropic = require("src.providers.anthropic")
+
+return providers