From cddd61f061ccfdd6e838a6619d0af106dfad9d16 Mon Sep 17 00:00:00 2001
From: Barrett Ruth <br.barrettruth@gmail.com>
Date: Thu, 2 Oct 2025 23:20:51 -0400
Subject: [PATCH] config hard fail

---
 lua/cp/config.lua         |  8 ++++++++
 lua/cp/runner/execute.lua |  2 +-
 lua/cp/utils.lua          | 29 ++++++++++++++++++++++++++---
 3 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/lua/cp/config.lua b/lua/cp/config.lua
index 4788832..b5d56c5 100644
--- a/lua/cp/config.lua
+++ b/lua/cp/config.lua
@@ -52,7 +52,10 @@
 ---@field picker? string|nil
 
 local M = {}
+
 local constants = require('cp.constants')
+local logger = require('cp.log')
+local utils = require('cp.utils')
 
 local default_contest_config = {
   cpp = {
@@ -249,6 +252,11 @@ function M.setup(user_config)
     end
   end
 
+  local ok, err = utils.check_required_runtime()
+  if not ok then
+    error('[cp.nvim] ' .. err)
+  end
+
   return config
 end
 
diff --git a/lua/cp/runner/execute.lua b/lua/cp/runner/execute.lua
index fe3667c..115f56a 100644
--- a/lua/cp/runner/execute.lua
+++ b/lua/cp/runner/execute.lua
@@ -123,7 +123,7 @@ function M.run(cmd, stdin, timeout_ms, memory_mb)
   local code = r.code or 0
   local raw = r.stdout or ''
   local cleaned, peak_mb = parse_and_strip_time_v(raw)
-  local tled = (code == 124)
+  local tled = code == 124
 
   local signal = nil
   if code >= 128 then
diff --git a/lua/cp/utils.lua b/lua/cp/utils.lua
index 60c23d8..033c924 100644
--- a/lua/cp/utils.lua
+++ b/lua/cp/utils.lua
@@ -58,9 +58,7 @@ local function find_gnu_time()
   return _time_path, _time_reason
 end
 
---- Return the validated GNU time binary path
---- Fails closed: returns nil if GNU time is unavailable.
----@return string|nil path
+---@return string|nil path to GNU time binary
 function M.time_path()
   local path = find_gnu_time()
   return path
@@ -139,4 +137,29 @@ function M.update_buffer_content(bufnr, lines, highlights, namespace)
   end
 end
 
+function M.check_required_runtime()
+  if is_windows() then
+    return false, 'Windows is not supported'
+  end
+
+  if vim.fn.has('nvim-0.10.0') ~= 1 then
+    return false, 'Neovim 0.10.0+ required'
+  end
+
+  local cap = M.time_capability()
+  if not cap.ok then
+    return false, 'GNU time not found: ' .. (cap.reason or '')
+  end
+
+  if vim.fn.executable('uv') ~= 1 then
+    return false, 'uv not found (https://docs.astral.sh/uv/)'
+  end
+
+  if not M.setup_python_env() then
+    return false, 'failed to set up Python virtual environment'
+  end
+
+  return true
+end
+
 return M