feat(renderer): config for markdown rendering

Rather than only supporting `RenderMarkdown`, make it user configurable.
Also add `Markview` as another option if `RenderMarkdown` isn't present.

Author: cameronr

README.md

@@ -211,6 +211,7 @@ require('opencode').setup({
         max_files = 10,
         max_display_length = 50, -- Maximum length for file path display in completion, truncates from left with "..."
       },
+      on_data_rendered = nil, -- Called when new data is rendered (debounced to 250ms), useful to trigger markdown rendering. Set to false to disable default behavior of checking for RenderMarkdown and Markview
     },
   },
   context = {

lua/opencode/config.lua

@@ -99,6 +99,7 @@ M.defaults = {
       text = {
         wrap = false,
       },
+      on_data_rendered = nil,
     },
     completion = {
       file_sources = {

lua/opencode/types.lua

@@ -95,6 +95,7 @@
 ---@field output { tools: { show_output: boolean } }
 ---@field input { text: { wrap: boolean } }
 ---@field completion OpencodeCompletionConfig
+---@field on_data_rendered fun(ctx: { buf: integer, win: integer })|nil
 
 ---@class OpencodeContextConfig
 ---@field enabled boolean

lua/opencode/ui/renderer.lua

@@ -11,6 +11,22 @@ M._subscriptions = {}
 M._prev_line_count = 0
 M._render_state = RenderState.new()
 
+local trigger_on_data_rendered = require('opencode.util').debounce(function()
+  local cb_type = type(config.ui.on_data_rendered)
+
+  if cb_type == 'boolean' then
+    return
+  end
+
+  if cb_type == 'function' then
+    pcall(config.ui.on_data_rendered, state.windows.output_buf, state.windows.output_win)
+  elseif vim.fn.exists(':RenderMarkdown') > 0 then
+    vim.cmd(':RenderMarkdown')
+  elseif vim.fn.exists(':Markview') then
+    vim.cmd(':Markview render ' .. state.windows.output_buf)
+  end
+end, 250)
+
 ---Reset renderer state
 function M.reset()
   M._prev_line_count = 0
@@ -21,6 +37,7 @@ function M.reset()
   state.messages = {}
   state.last_user_message = nil
   state.current_permission = nil
+  trigger_on_data_rendered()
 end
 
 ---Set up all subscriptions, for both local and server events
@@ -145,11 +162,10 @@ function M.render_output(output_data)
     return
   end
 
-  -- FIXME: add actions to RenderState?
-
   output_window.set_lines(output_data.lines)
   output_window.clear_extmarks()
   output_window.set_extmarks(output_data.extmarks)
+  M._scroll_to_bottom()
 end
 
 ---Auto-scroll to bottom if user was already at bottom
@@ -170,6 +186,8 @@ function M._scroll_to_bottom()
 
   local was_at_bottom = (botline >= prev_line_count) or prev_line_count == 0
 
+  trigger_on_data_rendered()
+
   if is_focused and cursor_row < prev_line_count - 1 then
     return
   end

lua/opencode/ui/ui.lua

@@ -11,12 +11,6 @@ local topbar = require('opencode.ui.topbar')
 function M.scroll_to_bottom()
   local line_count = vim.api.nvim_buf_line_count(state.windows.output_buf)
   vim.api.nvim_win_set_cursor(state.windows.output_win, { line_count, 0 })
-
-  -- TODO: shouldn't have hardcoded calls to render_markdown,
-  -- should support user callbacks
-  vim.defer_fn(function()
-    output_renderer.render_markdown()
-  end, 200)
 end
 
 ---@param windows OpencodeWindowState
@@ -188,7 +182,6 @@ function M.clear_output()
   output_window.clear()
   footer.clear()
   topbar.render()
-  output_renderer.render_markdown()
   -- state.restore_points = {}
 end
 
@@ -199,9 +192,6 @@ end
 function M.render_lines(lines)
   M.clear_output()
   renderer.render_lines(lines)
-
-  -- FIXME: rehook up markdown at some point (user provided callback?)
-  -- output_renderer.render_markdown()
 end
 
 function M.select_session(sessions, cb)