;;; package --- gptel
;;; Commentary:
;;; A simple LLM client for Emacs.
;;; https://github.com/karthink/gptel
;;; Code:

(use-package gptel
  :ensure t
  :defer t
  :config
  ;; Major mode used for chat buffers: 'org-mode or 'markdown-mode.
  (setq gptel-default-mode 'org-mode)

  ;; API keys: each backend below uses #'gptel-api-key-from-auth-source,
  ;; which looks up the backend's host with login "apikey" in auth-source.
  ;; Add these lines to ~/.authinfo.gpg:
  ;;
  ;;   machine openrouter.ai login apikey password <OPENROUTER-KEY>
  ;;   machine api.venice.ai login apikey password <VENICE-KEY>
  ;;
  ;; (Create keys at https://openrouter.ai/keys and
  ;; https://venice.ai/settings/api-key respectively.)
  ;;
  ;; Note: OpenCode cannot be used as a gptel backend: its HTTP API is
  ;; for driving agent sessions, not an OpenAI-compatible LLM endpoint,
  ;; and its own provider authenticates with an account, not an API key.

  ;; OpenRouter (default backend): OpenAI-compatible gateway to many
  ;; providers.  Model IDs can be browsed at https://openrouter.ai/models
  (setq gptel-backend
        (gptel-make-openai "OpenRouter"
                           :host "openrouter.ai"
                           :endpoint "/api/v1/chat/completions"
                           :key #'gptel-api-key-from-auth-source
                           :stream t
                           :models '(anthropic/claude-sonnet-5.5
                                     anthropic/claude-haiku-5.5
                                     openai/gpt-6.1-sol
                                     google/gemini-4-argon
                                     z-ai/glm-5.3-prime
                                     z-ai/glm-5.3-flashx
                                     z-ai/glm-5.3-flash
                                     z-ai/glm-5.2
                                     deepseek/deepseek-v4.1-flash
                                     qwen/qwen3.8-max-prime
                                     x-ai/grok-4.7
                                     moonshotai/kimi-k3.1-pro))
        ;; Change the default model here, or per-session with the menu
        ;; (C-u C-c RET in a gptel buffer, then -m).
        gptel-model 'z-ai/glm-5.3-prime)

  ;; Venice (https://venice.ai): privacy-oriented, OpenAI-compatible
  ;; API with uncensored models.  Registered but not the default: pick
  ;; it per-session with `M-x gptel-venice' (below) or the menu
  ;; (C-u C-c RET, then -m), or make it the default:
  ;;
  ;; (setq gptel-backend (gptel-get-backend "Venice")
  ;;       gptel-model 'zai-org-glm-5)
  (gptel-make-openai "Venice"
                     :host "api.venice.ai"
                     :endpoint "/api/v1/chat/completions"
                     :key #'gptel-api-key-from-auth-source
                     :stream t
                     :models '(zai-org-glm-5     ;Venice's default model
                               z-ai-glm-5-3
                               z-ai-glm-5-3-flash
                               venice-uncensored-1-2
                               claude-sonnet-5-5
                               claude-opus-5-5
                               deepseek-v4-1-flash
                               kimi-k3-1-pro))

  ;; In org chat buffers, only send the current heading's tree as
  ;; context instead of the whole buffer:
  ;;
  ;; (setq gptel-org-branching-context t)
  )

;; Start or switch to a chat on a specific backend, without touching
;; the global default.  An existing chat buffer keeps its chosen
;; model; a new chat gets MODEL.
(defun gptel--backend-chat (backend-name model)
  "Start or switch to a gptel chat using BACKEND-NAME and MODEL.
The global default backend is not changed."
  (let* ((backend (gptel-get-backend backend-name))
         (buffer (gptel (concat "*" backend-name "*"))))
    (with-current-buffer buffer
      (setq-local gptel-backend backend)
      (unless (memq gptel-model (gptel-backend-models backend))
        (setq-local gptel-model model)))
    (display-buffer buffer gptel-display-buffer-action)
    buffer))

(defun gptel-openrouter ()
  "Start or switch to a gptel chat using OpenRouter."
  (interactive)
  (require 'gptel)                 ;deferred by use-package above
  (gptel--backend-chat "OpenRouter" 'z-ai/glm-5.3-prime))

(defun gptel-venice ()
  "Start or switch to a gptel chat using Venice."
  (interactive)
  (require 'gptel)
  (gptel--backend-chat "Venice" 'zai-org-glm-5))

;; Usage:
;;   M-x gptel            start a dedicated chat buffer (default backend)
;;   M-x gptel-openrouter start or switch to a chat on OpenRouter
;;   M-x gptel-venice     start or switch to a chat on Venice
;;   M-x gptel-send       send the region (or text up to point) from any buffer
;;   M-x gptel-rewrite    rewrite/refactor the selected region
;;   C-c RET              send the query
;;   C-u C-c RET          menu: switch backend/model with -m, etc.
;;
;; Uncomment for global shortcuts:
;; (global-set-key (kbd "C-c g") #'gptel)
;; (global-set-key (kbd "C-c o") #'gptel-openrouter)
;; (global-set-key (kbd "C-c v") #'gptel-venice)

(provide 'init-gptel)

;;; init-gptel.el ends here