feat: refactor file structure

lua/cp/ui/window.lua

@@ -0,0 +1,144 @@
+---@class WindowState
+---@field windows table<integer, WindowData>
+---@field current_win integer
+---@field layout string
+
+---@class WindowData
+---@field bufnr integer
+---@field view table
+---@field width integer
+---@field height integer
+
+local M = {}
+local constants = require('cp.constants')
+
+---@return WindowState
+function M.save_layout()
+  local windows = {}
+  for _, win in ipairs(vim.api.nvim_list_wins()) do
+    if vim.api.nvim_win_is_valid(win) then
+      local bufnr = vim.api.nvim_win_get_buf(win)
+      windows[win] = {
+        bufnr = bufnr,
+        view = vim.fn.winsaveview(),
+        width = vim.api.nvim_win_get_width(win),
+        height = vim.api.nvim_win_get_height(win),
+      }
+    end
+  end
+
+  return {
+    windows = windows,
+    current_win = vim.api.nvim_get_current_win(),
+    layout = vim.fn.winrestcmd(),
+  }
+end
+
+---@param state? WindowState
+---@param tile_fn? fun(source_buf: integer, input_buf: integer, output_buf: integer)
+function M.restore_layout(state, tile_fn)
+  vim.validate({
+    state = { state, { 'table', 'nil' }, true },
+    tile_fn = { tile_fn, { 'function', 'nil' }, true },
+  })
+
+  if not state then
+    return
+  end
+
+  vim.cmd.diffoff()
+
+  local problem_id = vim.fn.expand('%:t:r')
+  if problem_id == '' then
+    for win, win_state in pairs(state.windows) do
+      if vim.api.nvim_win_is_valid(win) and vim.api.nvim_buf_is_valid(win_state.bufnr) then
+        local bufname = vim.api.nvim_buf_get_name(win_state.bufnr)
+        if
+          not bufname:match('%.in$')
+          and not bufname:match('%.out$')
+          and not bufname:match('%.expected$')
+        then
+          problem_id = vim.fn.fnamemodify(bufname, ':t:r')
+          break
+        end
+      end
+    end
+  end
+
+  if problem_id ~= '' then
+    vim.cmd('silent only')
+
+    local base_fp = vim.fn.getcwd()
+    local input_file = ('%s/io/%s.in'):format(base_fp, problem_id)
+    local output_file = ('%s/io/%s.out'):format(base_fp, problem_id)
+    local source_files = vim.fn.glob(problem_id .. '.*')
+    local source_file
+    if source_files ~= '' then
+      local files = vim.split(source_files, '\n')
+      local known_extensions = vim.tbl_keys(constants.filetype_to_language)
+      for _, file in ipairs(files) do
+        local ext = vim.fn.fnamemodify(file, ':e')
+        if vim.tbl_contains(known_extensions, ext) then
+          source_file = file
+          break
+        end
+      end
+      source_file = source_file or files[1]
+    end
+
+    if not source_file or vim.fn.filereadable(source_file) == 0 then
+      return
+    end
+
+    vim.cmd.edit(source_file)
+    local source_buf = vim.api.nvim_get_current_buf()
+    local input_buf = vim.fn.bufnr(input_file, true)
+    local output_buf = vim.fn.bufnr(output_file, true)
+
+    if tile_fn then
+      tile_fn(source_buf, input_buf, output_buf)
+    else
+      M.default_tile(source_buf, input_buf, output_buf)
+    end
+  else
+    vim.cmd(state.layout)
+
+    for win, win_state in pairs(state.windows) do
+      if vim.api.nvim_win_is_valid(win) then
+        vim.api.nvim_set_current_win(win)
+        if vim.api.nvim_get_current_buf() == win_state.bufnr then
+          vim.fn.winrestview(win_state.view)
+        end
+      end
+    end
+
+    if vim.api.nvim_win_is_valid(state.current_win) then
+      vim.api.nvim_set_current_win(state.current_win)
+    end
+  end
+end
+
+---@param source_buf integer
+---@param input_buf integer
+---@param output_buf integer
+local function default_tile(source_buf, input_buf, output_buf)
+  vim.validate({
+    source_buf = { source_buf, 'number' },
+    input_buf = { input_buf, 'number' },
+    output_buf = { output_buf, 'number' },
+  })
+
+  vim.api.nvim_set_current_buf(source_buf)
+  vim.cmd.vsplit()
+  vim.api.nvim_set_current_buf(output_buf)
+  vim.bo.filetype = 'cp'
+  vim.cmd(('vertical resize %d'):format(math.floor(vim.o.columns * 0.3)))
+  vim.cmd.split()
+  vim.api.nvim_set_current_buf(input_buf)
+  vim.bo.filetype = 'cp'
+  vim.cmd.wincmd('h')
+end
+
+M.default_tile = default_tile
+
+return M