dotfiles/config/linux-dev/nvim/lua/custom/navigation.lua

vim.keymap.set('n', '<leader>f', function()
  vim.cmd('FuzzyLive')
end, { desc = 'Open fuzzy file finder' })

-- Minimal realtime fuzzy finder in pure Neovim Lua (no plugins)
local Fuzzy = {}

function Fuzzy.open()
  if Fuzzy.active then
    Fuzzy.close()
  end
  Fuzzy.active = true

  -- Collect all files once (cached for speed)
  -- Fuzzy.files = vim.fn.globpath('.', '**/*', 0, 1)

  local handle = io.popen('fdfind --type f --hidden --exclude .git')
  if handle then
    local result = handle:read('*a')
    handle:close()
    Fuzzy.files = vim.split(result, '\n', { trimempty = true })
  else
    Fuzzy.files = {}
  end
  Fuzzy.matches = Fuzzy.files
  Fuzzy.cursor = 1

  -- Create input and result buffers
  Fuzzy.input_buf = vim.api.nvim_create_buf(false, true)
  Fuzzy.result_buf = vim.api.nvim_create_buf(false, true)

  -- Floating window sizes
  local width = math.floor(vim.o.columns * 0.6)
  local height = 15
  local row = math.floor((vim.o.lines - height) / 2)
  local col = math.floor((vim.o.columns - width) / 2)

  -- Input window (top)
  Fuzzy.input_win = vim.api.nvim_open_win(Fuzzy.input_buf, true, {
    relative = 'editor',
    row = row,
    col = col,
    width = width,
    height = 1,
    style = 'minimal',
    border = 'rounded',
  })
  vim.api.nvim_buf_set_option(Fuzzy.input_buf, 'buftype', 'prompt')
  vim.fn.prompt_setprompt(Fuzzy.input_buf, 'Search: ')

  -- Results window (below)
  Fuzzy.result_win = vim.api.nvim_open_win(Fuzzy.result_buf, false, {
    relative = 'editor',
    row = row + 2,
    col = col,
    width = width,
    height = height - 2,
    style = 'minimal',
    border = 'single',
  })

  -- Draw initial result list
  Fuzzy:update_results('')

  ------------------------------------------------------------------
  -- 🟢 Real-time fuzzy filtering
  ------------------------------------------------------------------
  vim.api.nvim_create_autocmd({ 'TextChangedI', 'TextChangedP' }, {
    buffer = Fuzzy.input_buf,
    callback = function()
      local text = vim.fn.getline('.')
      text = text:gsub('^Search:%s*', '')
      Fuzzy:update_results(text)
    end,
  })

  ------------------------------------------------------------------
  -- 🟢 Keybindings in input window
  ------------------------------------------------------------------
  vim.keymap.set('i', '<C-n>', function()
    if not Fuzzy.matches or #Fuzzy.matches == 0 then
      return
    end
    Fuzzy.cursor = math.min(Fuzzy.cursor + 1, #Fuzzy.matches)
    Fuzzy:highlight_selection()
  end, { buffer = Fuzzy.input_buf })

  vim.keymap.set('i', '<C-p>', function()
    if not Fuzzy.matches or #Fuzzy.matches == 0 then
      return
    end
    Fuzzy.cursor = math.max(Fuzzy.cursor - 1, 1)
    Fuzzy:highlight_selection()
  end, { buffer = Fuzzy.input_buf })

  vim.keymap.set('i', '<CR>', function()
    local choice = Fuzzy.matches[Fuzzy.cursor]
    if choice then
      Fuzzy.close()
      vim.cmd('edit ' .. vim.fn.fnameescape(choice))
    end
  end, { buffer = Fuzzy.input_buf })

  vim.keymap.set('i', '<Esc>', function()
    Fuzzy.close()
  end, { buffer = Fuzzy.input_buf })

  vim.cmd('startinsert')
end

--------------------------------------------------------------------
-- 🔵 Core update + display logic
--------------------------------------------------------------------
function Fuzzy:update_results(text)
  if text == '' then
    Fuzzy.matches = Fuzzy.files
  else
    Fuzzy.matches = vim.fn.matchfuzzy(Fuzzy.files, text)
  end

  if #Fuzzy.matches == 0 then
    vim.api.nvim_buf_set_lines(Fuzzy.result_buf, 0, -1, false, { '-- no matches --' })
    Fuzzy.cursor = 1
    return
  end

  -- Limit to first 50 results for performance
  local display = {}
  for i = 1, math.min(#Fuzzy.matches, 50) do
    table.insert(display, Fuzzy.matches[i])
  end

  vim.api.nvim_buf_set_lines(Fuzzy.result_buf, 0, -1, false, display)
  Fuzzy.cursor = 1
  Fuzzy:highlight_selection()
end

--------------------------------------------------------------------
-- 🔵 Highlight the selected file
--------------------------------------------------------------------
function Fuzzy:highlight_selection()
  if not Fuzzy.result_buf then
    return
  end
  vim.api.nvim_buf_clear_namespace(Fuzzy.result_buf, 0, 0, -1)
  if Fuzzy.matches and Fuzzy.matches[Fuzzy.cursor] then
    vim.api.nvim_buf_add_highlight(Fuzzy.result_buf, 0, 'Visual', Fuzzy.cursor - 1, 0, -1)
  end
end

--------------------------------------------------------------------
-- 🔴 Clean up
--------------------------------------------------------------------
function Fuzzy.close()
  if Fuzzy.input_win and vim.api.nvim_win_is_valid(Fuzzy.input_win) then
    vim.api.nvim_win_close(Fuzzy.input_win, true)
  end
  if Fuzzy.result_win and vim.api.nvim_win_is_valid(Fuzzy.result_win) then
    vim.api.nvim_win_close(Fuzzy.result_win, true)
  end
  Fuzzy.active = false
end

--------------------------------------------------------------------
-- 🧩 Command to launch
--------------------------------------------------------------------
vim.api.nvim_create_user_command('FuzzyLive', function()
  Fuzzy.open()
end, {})

return Fuzzy