fix: synchronous problem fetch

lua/cp/cache.lua

@@ -11,13 +11,10 @@
 
 ---@class ContestListData
 ---@field contests table[]
----@field cached_at number
 
 ---@class ContestData
 ---@field problems Problem[]
----@field scraped_at string
 ---@field test_cases? CachedTestCase[]
----@field test_cases_cached_at? number
 ---@field timeout_ms? number
 ---@field memory_mb? number
 ---@field interactive? boolean
@@ -121,7 +118,6 @@ function M.set_contest_data(platform, contest_id, problems)
 
   cache_data[platform][contest_id] = {
     problems = problems,
-    scraped_at = os.date('%Y-%m-%d'),
   }
 
   M.save()
@@ -194,7 +190,6 @@ function M.set_test_cases(
   end
 
   cache_data[platform][problem_key].test_cases = test_cases
-  cache_data[platform][problem_key].test_cases_cached_at = os.time()
   if timeout_ms then
     cache_data[platform][problem_key].timeout_ms = timeout_ms
   end
@@ -273,7 +268,6 @@ function M.set_contest_list(platform, contests)
 
   cache_data.contest_lists[platform] = {
     contests = contests,
-    cached_at = os.time(),
   }
 
   M.save()

lua/cp/commands/init.lua

@@ -8,7 +8,7 @@ local platforms = constants.PLATFORMS
 local actions = constants.ACTIONS
 
 local function parse_command(args)
-  if #args == 0 then
+  if vim.tbl_isempty(args) then
     return {
       type = 'restore_from_file',
     }

lua/cp/config.lua

@@ -270,7 +270,7 @@ function M.setup(user_config)
         end
       end
 
-      if #available_langs == 0 then
+      if vim.tbl_isemtpy(available_langs) then
         error('No language configurations found')
       end
 

lua/cp/pickers/fzf_lua.lua

@@ -8,7 +8,7 @@ local function contest_picker(platform)
   local fzf = require('fzf-lua')
   local contests = picker_utils.get_contests_for_platform(platform)
 
-  if #contests == 0 then
+  if vim.tbl_isempty(contests) then
     vim.notify(
       ('No contests found for platform: %s'):format(platform_display_name),
       vim.log.levels.WARN
@@ -27,7 +27,7 @@ local function contest_picker(platform)
     },
     actions = {
       ['default'] = function(selected)
-        if not selected or #selected == 0 then
+        if vim.tbl_isempty(selected) then
           return
         end
 
@@ -65,7 +65,7 @@ function M.pick()
     prompt = 'Select Platform> ',
     actions = {
       ['default'] = function(selected)
-        if not selected or #selected == 0 then
+        if vim.tbl_isempty(selected) then
           return
         end
 

lua/cp/pickers/init.lua

@@ -3,7 +3,7 @@ local M = {}
 local cache = require('cp.cache')
 local config = require('cp.config').get_config()
 local logger = require('cp.log')
-local utils = require('cp.utils')
+local scraper = require('cp.scraper')
 
 ---@class cp.PlatformItem
 ---@field id string Platform identifier (e.g. "codeforces", "atcoder", "cses")
@@ -40,157 +40,33 @@ end
 ---@param platform string Platform identifier (e.g. "codeforces", "atcoder")
 ---@return cp.ContestItem[]
 function M.get_contests_for_platform(platform)
-  logger.log('loading contests...', vim.log.levels.INFO, true)
+  logger.log(('Loading %s contests..'):format(platform), vim.log.levels.INFO, true)
 
   cache.load()
-  local cached_contests = cache.get_contest_list(platform)
-  if cached_contests then
-    return cached_contests
-  end
 
-  if not utils.setup_python_env() then
+  local picker_contests = cache.get_contest_list(platform) or {}
-    return {}
-  end
 
-  local plugin_path = utils.get_plugin_path()
+  if vim.tbl_isempty(picker_contests) then
-  local cmd = {
+    logger.log(('Cache miss on %s contests'):format(platform))
-    'uv',
+    local contests = scraper.scrape_contest_list(platform)
-    'run',
-    '--directory',
-    plugin_path,
-    '-m',
-    'scrapers.' .. platform,
-    'contests',
-  }
 
-  local result = vim
+    cache.set_contest_list(platform, contests)
-    .system(cmd, {
-      cwd = plugin_path,
-      text = true,
-      timeout = 30000,
-    })
-    :wait()
 
-  logger.log(('exit code: %d, stdout length: %d'):format(result.code, #(result.stdout or '')))
+    for _, contest in ipairs(contests or {}) do
-  if result.stderr and #result.stderr > 0 then
+      table.insert(picker_contests, {
-    logger.log(('stderr: %s'):format(result.stderr:sub(1, 200)))
+        id = contest.id,
-  end
+        name = contest.name,
-
+        display_name = contest.display_name,
-  if result.code ~= 0 then
-    logger.log(
-      ('Failed to load contests: %s'):format(result.stderr or 'unknown error'),
-      vim.log.levels.ERROR
-    )
-    return {}
-  end
-
-  logger.log(('stdout preview: %s'):format(result.stdout:sub(1, 100)))
-
-  local ok, data = pcall(vim.json.decode, result.stdout)
-  if not ok then
-    logger.log(('JSON parse error: %s'):format(tostring(data)), vim.log.levels.ERROR)
-    return {}
-  end
-  if not data.success then
-    logger.log(
-      ('Scraper returned success=false: %s'):format(data.error or 'no error message'),
-      vim.log.levels.ERROR
-    )
-    return {}
-  end
-
-  local contests = {}
-  for _, contest in ipairs(data.contests or {}) do
-    table.insert(contests, {
-      id = contest.id,
-      name = contest.name,
-      display_name = contest.display_name,
-    })
-  end
-
-  logger.log(('loaded %d contests'):format(#contests))
-  return contests
-end
-
----@param platform string Platform identifier
----@param contest_id string Contest identifier
----@return cp.ProblemItem[]
-function M.get_problems_for_contest(platform, contest_id)
-  logger.log('loading contest problems...', vim.log.levels.INFO, true)
-
-  local problems = {}
-
-  cache.load()
-  local contest_data = cache.get_contest_data(platform, contest_id)
-  if contest_data and contest_data.problems then
-    for _, problem in ipairs(contest_data.problems) do
-      table.insert(problems, {
-        id = problem.id,
-        name = problem.name,
-        display_name = problem.name,
       })
     end
-    return problems
   end
 
-  if not utils.setup_python_env() then
+  logger.log(
-    return problems
+    ('Loaded %d %s contests.'):format(#picker_contests, platform),
-  end
+    vim.log.levels.INFO,
-
+    true
-  local plugin_path = utils.get_plugin_path()
+  )
-  local cmd = {
+  return picker_contests
-    'uv',
-    'run',
-    '--directory',
-    plugin_path,
-    '-m',
-    'scrapers.' .. platform,
-    'metadata',
-    contest_id,
-  }
-
-  local result = vim
-    .system(cmd, {
-      cwd = plugin_path,
-      text = true,
-      timeout = 30000,
-    })
-    :wait()
-
-  if result.code ~= 0 then
-    logger.log(
-      ('Failed to scrape contest: %s'):format(result.stderr or 'unknown error'),
-      vim.log.levels.ERROR
-    )
-    return problems
-  end
-
-  local ok, data = pcall(vim.json.decode, result.stdout)
-  if not ok then
-    logger.log('Failed to parse contest data', vim.log.levels.ERROR)
-    return problems
-  end
-  if not data.success then
-    logger.log(data.error or 'Contest scraping failed', vim.log.levels.ERROR)
-    return problems
-  end
-
-  if not data.problems or #data.problems == 0 then
-    logger.log('Contest has no problems available', vim.log.levels.WARN)
-    return problems
-  end
-
-  cache.set_contest_data(platform, contest_id, data.problems)
-
-  for _, problem in ipairs(data.problems) do
-    table.insert(problems, {
-      id = problem.id,
-      name = problem.name,
-      display_name = problem.name,
-    })
-  end
-
-  return problems
 end
 
 ---@param platform string Platform identifier

lua/cp/pickers/telescope.lua

@@ -13,7 +13,7 @@ local function contest_picker(opts, platform)
   local platform_display_name = constants.PLATFORM_DISPLAY_NAMES[platform] or platform
   local contests = picker_utils.get_contests_for_platform(platform)
 
-  if #contests == 0 then
+  if vim.tbl_isempty(contests) then
     vim.notify(
       ('No contests found for platform: %s'):format(platform_display_name),
       vim.log.levels.WARN

lua/cp/runner/run.lua

@@ -66,9 +66,9 @@ end
 local function parse_test_cases_from_cache(platform, contest_id, problem_id)
   local cache = require('cp.cache')
   cache.load()
-  local cached_test_cases = cache.get_test_cases(platform, contest_id, problem_id)
+  local cached_test_cases = cache.get_test_cases(platform, contest_id, problem_id) or {}
 
-  if not cached_test_cases or #cached_test_cases == 0 then
+  if vim.tbl_isempty(cached_test_cases) then
     return {}
   end
 
@@ -299,9 +299,9 @@ function M.load_test_cases(state)
     state.get_platform() or '',
     state.get_contest_id() or '',
     state.get_problem_id()
-  )
+  ) or {}
 
-  if #test_cases == 0 then
+  if vim.tbl_isempty(test_cases) then
     local input_file = state.get_input_file()
     local expected_file = state.get_expected_file()
     test_cases = parse_test_cases_from_files(input_file, expected_file)

lua/cp/scraper.lua

@@ -1,11 +1,42 @@
 local M = {}
-local cache = require('cp.cache')
 local utils = require('cp.utils')
 
-local function run_scraper(platform, subcommand, args, callback)
+local logger = require('cp.log')
+
+local function syshandle(result)
+  if result.code ~= 0 then
+    local msg = 'Scraper failed: ' .. (result.error or result.stderr or 'Unknown error')
+    logger.log(msg, vim.log.levels.ERROR)
+    return {
+      success = false,
+      error = msg,
+    }
+  end
+
+  local ok, data = pcall(vim.json.decode, result.stdout)
+  if not ok then
+    local msg = 'Failed to parse scraper output: ' .. tostring(data)
+    logger.log(msg, vim.log.levels.ERROR)
+    return {
+      success = false,
+      error = msg,
+    }
+  end
+
+  return {
+    success = true,
+    data = data,
+  }
+end
+
+local function run_scraper(platform, subcommand, args, opts)
   if not utils.setup_python_env() then
-    callback({ success = false, error = 'Python environment setup failed' })
+    local msg = 'Python environment setup failed'
-    return
+    logger.log(msg, vim.log.levels.ERROR)
+    return {
+      success = false,
+      message = msg,
+    }
   end
 
   local plugin_path = utils.get_plugin_path()
@@ -18,114 +49,96 @@ local function run_scraper(platform, subcommand, args, callback)
     'scrapers.' .. platform,
     subcommand,
   }
+  vim.list_extend(cmd, args)
 
-  for _, arg in ipairs(args or {}) do
+  local sysopts = {
-    table.insert(cmd, arg)
-  end
-
-  vim.system(cmd, {
-    cwd = plugin_path,
     text = true,
     timeout = 30000,
-  }, function(result)
+  }
-    if result.code ~= 0 then
-      callback({
-        success = false,
-        error = 'Scraper failed: ' .. (result.stderr or 'Unknown error'),
-      })
-      return
-    end
 
-    local ok, data = pcall(vim.json.decode, result.stdout)
+  if opts.sync then
-    if not ok then
+    local result = vim.system(cmd, sysopts):wait()
-      callback({
+    return syshandle(result)
-        success = false,
+  else
-        error = 'Failed to parse scraper output: ' .. tostring(data),
+    vim.system(cmd, sysopts, function(result)
-      })
+      return opts.on_exit(syshandle(result))
-      return
+    end)
-    end
+  end
-
-    callback(data)
-  end)
 end
 
 function M.scrape_contest_metadata(platform, contest_id, callback)
-  cache.load()
+  run_scraper(platform, 'metadata', { contest_id }, {
-
+    on_exit = function(result)
-  local cached = cache.get_contest_data(platform, contest_id)
+      if result.success and result.data.problems then
-  if cached then
+        callback(result.data.problems)
-    callback({ success = true, problems = cached.problems })
+      end
-    return
+    end,
-  end
+  })
-
-  run_scraper(platform, 'metadata', { contest_id }, function(result)
-    if result.success and result.problems then
-      cache.set_contest_data(platform, contest_id, result.problems)
-    end
-    callback(result)
-  end)
 end
 
-function M.scrape_contest_list(platform, callback)
+function M.scrape_contest_list(platform)
-  cache.load()
+  local result = run_scraper(platform, 'contests', {}, { sync = true })
-
+  if not result.success or not result.data.contests then
-  local cached = cache.get_contest_list(platform)
+    logger.log(('Could not scrape contests list for platform %s: %s'):format(platform, result.msg))
-  if cached then
+    return {}
-    callback({ success = true, contests = cached })
-    return
   end
 
-  run_scraper(platform, 'contests', {}, function(result)
+  return result.data.contests
-    if result.success and result.contests then
-      cache.set_contest_list(platform, result.contests)
-    end
-    callback(result)
-  end)
 end
 
 function M.scrape_problem_tests(platform, contest_id, problem_id, callback)
-  run_scraper(platform, 'tests', { contest_id, problem_id }, function(result)
+  run_scraper(platform, 'tests', { contest_id, problem_id }, {
-    if result.success and result.tests then
+    on_exit = function(result)
-      vim.schedule(function()
+      if result.success and result.data.tests then
-        local mkdir_ok = pcall(vim.fn.mkdir, 'io', 'p')
+        vim.schedule(function()
-        if mkdir_ok then
+          local mkdir_ok = pcall(vim.fn.mkdir, 'io', 'p')
-          local config = require('cp.config')
+          if mkdir_ok then
-          local base_name = config.default_filename(contest_id, problem_id)
+            local config = require('cp.config')
+            local base_name = config.default_filename(contest_id, problem_id)
 
-          for i, test_case in ipairs(result.tests) do
+            for i, test_case in ipairs(result.tests) do
-            local input_file = 'io/' .. base_name .. '.' .. i .. '.cpin'
+              local input_file = 'io/' .. base_name .. '.' .. i .. '.cpin'
-            local expected_file = 'io/' .. base_name .. '.' .. i .. '.cpout'
+              local expected_file = 'io/' .. base_name .. '.' .. i .. '.cpout'
 
-            local input_content = test_case.input:gsub('\r', '')
+              local input_content = test_case.input:gsub('\r', '')
-            local expected_content = test_case.expected:gsub('\r', '')
+              local expected_content = test_case.expected:gsub('\r', '')
 
-            pcall(vim.fn.writefile, vim.split(input_content, '\n', true), input_file)
+              pcall(
-            pcall(vim.fn.writefile, vim.split(expected_content, '\n', true), expected_file)
+                vim.fn.writefile,
+                vim.split(input_content, '\n', { trimempty = true }),
+                input_file
+              )
+              pcall(
+                vim.fn.writefile,
+                vim.split(expected_content, '\n', { trimempty = true }),
+                expected_file
+              )
+            end
           end
-        end
+        end)
-      end)
 
-      local cached_tests = {}
+        local cached_tests = {}
-      for i, test_case in ipairs(result.tests) do
+        for i, test_case in ipairs(result.tests) do
-        table.insert(cached_tests, {
+          table.insert(cached_tests, {
-          index = i,
+            index = i,
-          input = test_case.input,
+            input = test_case.input,
-          expected = test_case.expected,
+            expected = test_case.expected,
-        })
+          })
+        end
+
+        cache.set_test_cases(
+          platform,
+          contest_id,
+          problem_id,
+          cached_tests,
+          result.timeout_ms,
+          result.memory_mb
+        )
       end
 
-      cache.set_test_cases(
+      callback(result)
-        platform,
+    end,
-        contest_id,
+  })
-        problem_id,
-        cached_tests,
-        result.timeout_ms,
-        result.memory_mb
-      )
-    end
-
-    callback(result)
-  end)
 end
 
 return M

lua/cp/setup.lua

@@ -28,10 +28,10 @@ function M.set_platform(platform)
   return true
 end
 
+-- NOTE: this is backwards
 function M.setup_contest(platform, contest_id, problem_id, language)
   if not state.get_platform() then
     logger.log('No platform configured. Use :CP <platform> <contest> [...] first.')
-
     return
   end
 
@@ -42,6 +42,7 @@ function M.setup_contest(platform, contest_id, problem_id, language)
     return
   end
 
+  state.set_contest_id(contest_id)
   logger.log('fetching contests problems...', vim.log.levels.INFO, true)
 
   scraper.scrape_contest_metadata(platform, contest_id, function(result)
@@ -54,14 +55,13 @@ function M.setup_contest(platform, contest_id, problem_id, language)
     end
 
     local problems = result.problems
-    if not problems or #problems == 0 then
+    if vim.tbl_isempty(problems) then
       logger.log('no problems found in contest', vim.log.levels.ERROR)
       return
     end
 
     logger.log(('found %d problems'):format(#problems))
 
-    state.set_contest_id(contest_id)
     local target_problem = problem_id or problems[1].id
 
     if problem_id then
@@ -81,6 +81,7 @@ function M.setup_contest(platform, contest_id, problem_id, language)
       end
     end
 
+    -- NOTE: should setup buffer without a name, then save it with proper name later for immediate editing
     M.setup_problem(contest_id, target_problem, language)
 
     M.scrape_remaining_problems(platform, contest_id, problems)
@@ -161,6 +162,7 @@ function M.setup_problem(contest_id, problem_id, language)
   elseif vim.tbl_contains(config.scrapers, platform) then
     logger.log('loading test cases...')
 
+    -- TODO: caching should be here, not in scrpaer.lua
     scraper.scrape_problem_tests(platform, contest_id, problem_id, function(result)
       if result.success then
         logger.log(('loaded %d test cases for %s'):format(#(result.tests or {}), problem_id))
@@ -194,7 +196,7 @@ function M.scrape_remaining_problems(platform, contest_id, problems)
     end
   end
 
-  if #missing_problems == 0 then
+  if vim.tbl_isempty(missing_problems) then
     logger.log('all problems already cached')
     return
   end

lua/cp/ui/panel.lua

@@ -235,7 +235,7 @@ function M.toggle_run_panel(is_debug)
 
   local function navigate_test_case(delta)
     local test_state = run.get_run_panel_state()
-    if #test_state.test_cases == 0 then
+    if vim.tbl_isempty(test_state.test_cases) then
       return
     end
     test_state.current_index = (test_state.current_index + delta) % #test_state.test_cases

spec/execute_spec.lua

@@ -12,7 +12,7 @@ describe('cp.execute', function()
 
     vim.system = function(cmd, opts)
       table.insert(mock_system_calls, { cmd = cmd, opts = opts })
-      if not cmd or #cmd == 0 then
+      if vim.tbl_isempty(cmd) then
         return {
           wait = function()
             return { code = 0, stdout = '', stderr = '' }

spec/picker_spec.lua

@@ -90,101 +90,4 @@ describe('cp.picker', function()
       assert.equals('Beginner Contest 123 (ABC)', contests[1].display_name)
     end)
   end)
-
-  describe('get_problems_for_contest', function()
-    it('returns problems from cache when available', function()
-      local cache = require('cp.cache')
-      cache.load = function() end
-      cache.get_contest_data = function(_, _)
-        return {
-          problems = {
-            { id = 'a', name = 'Problem A' },
-            { id = 'b', name = 'Problem B' },
-          },
-        }
-      end
-
-      local problems = picker.get_problems_for_contest('test_platform', 'test_contest')
-      assert.is_table(problems)
-      assert.equals(2, #problems)
-      assert.equals('a', problems[1].id)
-      assert.equals('Problem A', problems[1].name)
-      assert.equals('Problem A', problems[1].display_name)
-    end)
-
-    it('falls back to scraping when cache miss', function()
-      local cache = require('cp.cache')
-      local utils = require('cp.utils')
-
-      cache.load = function() end
-      cache.get_contest_data = function(_, _)
-        return nil
-      end
-      cache.set_contest_data = function() end
-
-      utils.setup_python_env = function()
-        return true
-      end
-      utils.get_plugin_path = function()
-        return '/tmp'
-      end
-
-      vim.system = function()
-        return {
-          wait = function()
-            return {
-              code = 0,
-              stdout = vim.json.encode({
-                success = true,
-                problems = {
-                  { id = 'x', name = 'Problem X' },
-                },
-              }),
-            }
-          end,
-        }
-      end
-
-      picker = spec_helper.fresh_require('cp.pickers', { 'cp.pickers.init' })
-
-      local problems = picker.get_problems_for_contest('test_platform', 'test_contest')
-      assert.is_table(problems)
-      assert.equals(1, #problems)
-      assert.equals('x', problems[1].id)
-    end)
-
-    it('returns empty list when scraping fails', function()
-      local cache = require('cp.cache')
-      local utils = require('cp.utils')
-
-      cache.load = function() end
-      cache.get_contest_data = function(_, _)
-        return nil
-      end
-
-      utils.setup_python_env = function()
-        return true
-      end
-      utils.get_plugin_path = function()
-        return '/tmp'
-      end
-
-      vim.system = function()
-        return {
-          wait = function()
-            return {
-              code = 1,
-              stderr = 'Scraping failed',
-            }
-          end,
-        }
-      end
-
-      picker = spec_helper.fresh_require('cp.pickers', { 'cp.pickers.init' })
-
-      local problems = picker.get_problems_for_contest('test_platform', 'test_contest')
-      assert.is_table(problems)
-      assert.equals(0, #problems)
-    end)
-  end)
 end)