Feature/custom chat frontend

README.md

@@ -242,6 +242,64 @@ Please submit PRs adding new providers! 🙂
 
 ## 🚀 Usage
 
+### 💬 Chat — `require("opencode").chat()`
+
+Open a custom Neovim frontend for `opencode` with a floating window chat interface.
+
+- **Pure Neovim UI** — no terminal needed
+- **Real-time streaming** — see AI responses as they're generated
+- **Vim keybindings** — navigate with hjkl, yank messages, and more
+- **Session management** — create new sessions, interrupt responses
+- **Markdown rendering** — syntax highlighting for code blocks
+- **Configurable** — customize keymaps, provider, model, and window size
+
+#### Configuration
+
+Enable the chat frontend and configure it in your `vim.g.opencode_opts`:
+
+```lua
+vim.g.opencode_opts = {
+  chat = {
+    enabled = true,  -- Enable custom chat UI instead of terminal TUI (default: false)
+    provider_id = "anthropic",  -- AI provider (default: "anthropic")
+    model_id = "claude-3-5-sonnet-20241022",  -- AI model (default: "claude-3-5-sonnet-20241022")
+    width = 0.6,  -- Window width as fraction of editor width (default: 0.6)
+    height = 0.7,  -- Window height as fraction of editor height (default: 0.7)
+    keymaps = {
+      open = "<leader>oc",  -- Keymap to open chat (default: "<leader>oc")
+      send = { "i", "a" },  -- Keymaps to send message (default: {"i", "a"})
+      close = { "q", "<Esc>" },  -- Keymaps to close chat (default: {"q", "<Esc>"})
+      new_session = "n",  -- Keymap for new session (default: "n")
+      interrupt = "<C-c>",  -- Keymap to interrupt (default: "<C-c>")
+      yank = "yy",  -- Keymap to yank message (default: "yy")
+    }
+  }
+}
+```
+
+When `enabled = true`, the global keymap will be automatically set up. You can also manually call the chat function:
+
+```lua
+vim.keymap.set('n', '<leader>oc', function()
+  require('opencode').chat()
+end, { desc = "Open OpenCode Chat" })
+```
+
+#### Keybindings
+
+Default keybindings in the chat window (all configurable):
+
+| Key | Action |
+| --- | ------ |
+| `<leader>oc` | Open chat window (global) |
+| `i` or `a` | Send a message |
+| `n` | Start a new session |
+| `q` or `<Esc>` | Close chat window |
+| `yy` | Yank current message to clipboard |
+| `<C-c>` | Interrupt current response |
+| `j`/`k` | Navigate up/down |
+| `gg`/`G` | Jump to top/bottom |
+
 ### ✍️ Ask — `require("opencode").ask()`
 
 Input a prompt for `opencode`.

ftplugin/opencode_chat.lua

@@ -0,0 +1,33 @@
+-- Filetype plugin for opencode_chat buffers
+-- Provides syntax highlighting for chat messages
+
+-- Enable markdown-like syntax for code blocks
+vim.bo.commentstring = "<!-- %s -->"
+
+-- Set up basic syntax highlighting
+vim.cmd([[
+  syntax match OpencodeHeaderUser "^### You$"
+  syntax match OpencodeHeaderAssistant "^### Assistant$"
+  syntax match OpencodeHeaderSystem "^### System$"
+  syntax match OpencodeSeparator "^─\+$"
+  syntax match OpencodeTypingIndicator "^▋$"
+
+  highlight default link OpencodeHeaderUser Title
+  highlight default link OpencodeHeaderAssistant Special
+  highlight default link OpencodeHeaderSystem Comment
+  highlight default link OpencodeSeparator Comment
+  highlight default link OpencodeTypingIndicator WarningMsg
+]])
+
+-- Enable treesitter markdown highlighting if available
+local ok, ts_highlight = pcall(require, "vim.treesitter.highlighter")
+if ok then
+  ok = pcall(vim.treesitter.start, vim.api.nvim_get_current_buf(), "markdown")
+  if not ok then
+    -- Fallback to basic markdown syntax
+    vim.cmd("runtime! syntax/markdown.vim")
+  end
+else
+  -- Fallback to basic markdown syntax
+  vim.cmd("runtime! syntax/markdown.vim")
+end

lua/opencode.lua

@@ -14,4 +14,6 @@ M.stop = require("opencode.provider").stop
 
 M.statusline = require("opencode.status").statusline
 
+M.chat = require("opencode.ui.chat_init").start_chat
+
 return M

lua/opencode/config.lua

@@ -32,12 +32,31 @@ vim.g.opencode_opts = vim.g.opencode_opts
 ---Supports [`snacks.picker`](https://github.com/folke/snacks.nvim/blob/main/docs/picker.md).
 ---@field select? opencode.select.Opts
 ---
+---Options for `chat()`.
+---@field chat? opencode.chat.Opts
+---
 ---Options for `opencode` event handling.
 ---@field events? opencode.events.Opts
 ---
 ---Provide an integrated `opencode` when one is not found.
 ---@field provider? opencode.Provider|opencode.provider.Opts
 
+---@class opencode.chat.Opts
+---@field enabled? boolean Enable custom chat UI instead of terminal TUI (default: false)
+---@field provider_id? string AI provider to use (default: "anthropic")
+---@field model_id? string AI model to use (default: "claude-3-5-sonnet-20241022")
+---@field width? number Width of chat window as fraction of editor width (default: 0.6)
+---@field height? number Height of chat window as fraction of editor height (default: 0.7)
+---@field keymaps? opencode.chat.Keymaps Keymaps for chat window
+
+---@class opencode.chat.Keymaps
+---@field open? string|string[] Keymap(s) to open chat window (default: "<leader>oc")
+---@field send? string|string[] Keymap(s) to send message in chat (default: {"i", "a"})
+---@field close? string|string[] Keymap(s) to close chat window (default: {"q", "<Esc>"})
+---@field new_session? string Keymap to start new session (default: "n")
+---@field interrupt? string Keymap to interrupt response (default: "<C-c>")
+---@field yank? string Keymap to yank current message (default: "yy")
+
 ---@class opencode.Prompt : opencode.api.prompt.Opts
 ---@field prompt string The prompt to send to `opencode`.
 ---@field ask? boolean Call `ask(prompt)` instead of `prompt(prompt)`. Useful for prompts that expect additional user input.
@@ -105,6 +124,21 @@ local defaults = {
       },
     },
   },
+  chat = {
+    enabled = false,
+    provider_id = "anthropic",
+    model_id = "claude-3-5-sonnet-20241022",
+    width = 0.6,
+    height = 0.7,
+    keymaps = {
+      open = "<leader>oc",
+      send = { "i", "a" },
+      close = { "q", "<Esc>" },
+      new_session = "n",
+      interrupt = "<C-c>",
+      yank = "yy",
+    },
+  },
   events = {
     enabled = true,
     reload = true,