feat(navigation): jump to file at cursor in output window

resolve_file_at_cursor parses markdown links, file:// URIs, action
lines, and diff hunks. jump_to_file_at_cursor opens the file in
state.last_code_win_before_opencode (winnr('#') fallback) using a
silent :buffer/:edit helper to avoid re-triggering autocmds.

Author: phanen

lua/opencode/commands/handlers/workflow.lua

@@ -277,6 +277,10 @@ function M.actions.prev_message()
   require('opencode.ui.navigation').goto_prev_message()
 end
 
+function M.actions.jump_to_file()
+  require('opencode.ui.navigation').jump_to_file_at_cursor()
+end
+
 function M.actions.toggle_tool_output()
   local action_text = config.ui.output.tools.show_output and 'Hiding' or 'Showing'
   vim.notify(action_text .. ' tool output display', vim.log.levels.INFO)
@@ -458,6 +462,10 @@ M.command_defs = {
     desc = 'Navigate to previous message in output window',
     execute = M.actions.prev_message,
   },
+  jump_to_file = {
+    desc = 'Jump to file at cursor in output window',
+    execute = M.actions.jump_to_file,
+  },
   debug_output = {
     desc = 'Open raw output debug view',
     execute = M.actions.debug_output,

lua/opencode/ui/navigation.lua

@@ -2,6 +2,7 @@ local M = {}
 
 local state = require('opencode.state')
 local renderer = require('opencode.ui.renderer')
+local output_window = require('opencode.ui.output_window')
 
 function M.goto_message_by_id(message_id)
   require('opencode.ui.ui').focus_output()
@@ -61,4 +62,141 @@ function M.goto_prev_message()
   vim.api.nvim_win_set_cursor(win, { 1, 0 })
 end
 
+---Resolve file and line number at cursor position in the output buffer.
+---@return { path: string, line: number? }?
+function M.resolve_file_at_cursor()
+  local windows = state.windows or {}
+  local win = windows.output_win
+  local buf = windows.output_buf
+
+  if not win or not buf or not vim.api.nvim_win_is_valid(win) then
+    return nil
+  end
+
+  local cursor = vim.api.nvim_win_get_cursor(win)
+  local line_num = cursor[1]
+  local line = vim.api.nvim_buf_get_lines(buf, line_num - 1, line_num, false)[1]
+
+  if not line then
+    return nil
+  end
+
+  -- 1. Check for markdown-style file links: [`path`](path)
+  local path = line:match('%[`([^`]+)%`%]%([^%)]+%)')
+  if path then
+    return { path = path }
+  end
+
+  -- 2. Check for file:// style links: `file://path/to/file.lua:line`
+  local f_path, f_line = line:match('`file://([^:`]+):?(%d*)`')
+  if f_path then
+    return { path = f_path, line = tonumber(f_line) }
+  end
+
+  -- 3. Check for action lines: **icon tool** `path`
+  path = line:match('%*%*.-%*%*%s+`([^`]+)`')
+  if path then
+    return { path = path }
+  end
+
+  -- 4. Check for diff hunk: look for the nearest file path upwards
+  local file_path = nil
+  for i = line_num, 1, -1 do
+    local l = vim.api.nvim_buf_get_lines(buf, i - 1, i, false)[1]
+    if l then
+      local p = l:match('%[`([^`]+)%`%]%([^%)]+%)') or l:match('%*%*.-%*%*%s+`([^`]+)`')
+      if p then
+        file_path = p
+        break
+      end
+    end
+  end
+
+  if not file_path then
+    return nil
+  end
+
+  -- Check if we are on a diff line with a line number in the gutter
+  local ns = output_window.namespace
+  local extmarks = vim.api.nvim_buf_get_extmarks(buf, ns, { line_num - 1, 0 }, { line_num - 1, -1 }, { details = true })
+  local ln = nil
+  for _, extmark in ipairs(extmarks) do
+    local details = extmark[4]
+    if details and details.virt_text then
+      for _, vt in ipairs(details.virt_text) do
+        local val = tonumber(vim.trim(vt[1]))
+        if val then
+          ln = val
+          break
+        end
+      end
+    end
+    if ln then
+      break
+    end
+  end
+
+  return { path = file_path, line = ln }
+end
+
+---Open a file in the current window without triggering BufRead/BufNew autocmds.
+---Falls back to :edit if the file isn't loaded in any buffer yet.
+---@param path string
+local function open_silent(path)
+  local escaped = vim.fn.fnameescape(path)
+  if not pcall(vim.cmd, 'buffer ' .. escaped) then
+    pcall(vim.cmd, 'edit ' .. escaped)
+  end
+end
+
+---Jump to the file at the cursor position.
+function M.jump_to_file_at_cursor()
+  local resolved = M.resolve_file_at_cursor()
+  if not resolved then
+    return
+  end
+
+  local path = resolved.path
+  if not vim.uv.fs_stat(path) then
+    -- Try relative to CWD if it's not absolute or not found
+    local absolute = vim.fn.fnamemodify(path, ':p')
+    if vim.uv.fs_stat(absolute) then
+      path = absolute
+    else
+      -- Try finding it
+      local found = vim.fn.findfile(path, '.;')
+      if found ~= '' then
+        path = found
+      end
+    end
+  end
+
+  if not vim.uv.fs_stat(path) then
+    return
+  end
+
+  local target_win = state.last_code_win_before_opencode
+  if not target_win or not vim.api.nvim_win_is_valid(target_win) then
+    local alt_win = vim.fn.win_getid(vim.fn.winnr('#'))
+    if alt_win ~= 0 and vim.api.nvim_win_is_valid(alt_win) then
+      target_win = alt_win
+    end
+  end
+
+  if target_win and vim.api.nvim_win_is_valid(target_win) then
+    vim.api.nvim_win_call(target_win, function()
+      open_silent(path)
+      if resolved.line then
+        pcall(vim.api.nvim_win_set_cursor, 0, { resolved.line, 0 })
+      end
+    end)
+    vim.api.nvim_set_current_win(target_win)
+  else
+    open_silent(path)
+    if resolved.line then
+      pcall(vim.api.nvim_win_set_cursor, 0, { resolved.line, 0 })
+    end
+  end
+end
+
 return M