refactor(llm): cleanup providers for future ops (closes #134) (#147)

support allow_insecure and proxy ops

Signed-off-by: Aaron Pham <contact@aarnphm.xyz>

lua/avante/providers/openai.lua

@@ -0,0 +1,110 @@
+local Utils = require("avante.utils")
+local Config = require("avante.config")
+local P = require("avante.providers")
+
+---@class OpenAIChatResponse
+---@field id string
+---@field object "chat.completion" | "chat.completion.chunk"
+---@field created integer
+---@field model string
+---@field system_fingerprint string
+---@field choices? OpenAIResponseChoice[]
+---@field usage {prompt_tokens: integer, completion_tokens: integer, total_tokens: integer}
+---
+---@class OpenAIResponseChoice
+---@field index integer
+---@field delta OpenAIMessage
+---@field logprobs? integer
+---@field finish_reason? "stop" | "length"
+---
+---@class OpenAIMessage
+---@field role? "user" | "system" | "assistant"
+---@field content string
+---
+---@class AvanteProviderFunctor
+local M = {}
+
+M.API_KEY = "OPENAI_API_KEY"
+
+M.has = function()
+  return os.getenv(M.API_KEY) and true or false
+end
+
+M.parse_message = function(opts)
+  local user_prompt = opts.base_prompt
+    .. "\n\nCODE:\n"
+    .. "```"
+    .. opts.code_lang
+    .. "\n"
+    .. opts.code_content
+    .. "\n```"
+    .. "\n\nQUESTION:\n"
+    .. opts.question
+
+  if opts.selected_code_content ~= nil then
+    user_prompt = opts.base_prompt
+      .. "\n\nCODE CONTEXT:\n"
+      .. "```"
+      .. opts.code_lang
+      .. "\n"
+      .. opts.code_content
+      .. "\n```"
+      .. "\n\nCODE:\n"
+      .. "```"
+      .. opts.code_lang
+      .. "\n"
+      .. opts.selected_code_content
+      .. "\n```"
+      .. "\n\nQUESTION:\n"
+      .. opts.question
+  end
+
+  return {
+    { role = "system", content = opts.system_prompt },
+    { role = "user", content = user_prompt },
+  }
+end
+
+M.parse_response = function(data_stream, _, opts)
+  if data_stream:match('"%[DONE%]":') then
+    opts.on_complete(nil)
+    return
+  end
+  if data_stream:match('"delta":') then
+    ---@type OpenAIChatResponse
+    local json = vim.json.decode(data_stream)
+    if json.choices and json.choices[1] then
+      local choice = json.choices[1]
+      if choice.finish_reason == "stop" then
+        opts.on_complete(nil)
+      elseif choice.delta.content then
+        opts.on_chunk(choice.delta.content)
+      end
+    end
+  end
+end
+
+M.parse_curl_args = function(provider, code_opts)
+  local base, body_opts = P.parse_config(provider)
+
+  local headers = {
+    ["Content-Type"] = "application/json",
+  }
+  if not P.env.is_local("openai") then
+    headers["Authorization"] = "Bearer " .. os.getenv(M.API_KEY)
+  end
+
+  return {
+    url = Utils.trim(base.endpoint, { suffix = "/" }) .. "/v1/chat/completions",
+    proxy = base.proxy,
+    insecure = base.allow_insecure,
+    headers = headers,
+    body = vim.tbl_deep_extend("force", {
+      model = base.model,
+      messages = M.parse_message(code_opts),
+      stream = true,
+    }, body_opts),
+  }
+end
+
+return M