local ls = require('luasnip')
local types = require('luasnip.util.types')

-- configure luasnip
ls.config.set_config({
  enable_autosnippets = true,
  history = true,
  updateevents = 'TextChanged,TextChangedI',
  override_builtin = true,
  ext_opts = {
    [types.choiceNode] = {
      active = {
        virt_text = { { '◂    󰬊 ', 'NonText' } },
      },
    },
    [types.insertNode] = {
      active = {
        virt_text = { { '◂    󰬐 ', 'NonText' } },
      },
    },
  },
  snip_env = vim.tbl_deep_extend('error', ls.session.config.snip_env, {
    -- snippet helpers
    nl = function()
      return ls.t({ '', '' })
    end,
    exec = function(command)
      return ls.f(function(_, _, ...)
        local job = require('plenary.job'):new({
          command = vim.env.SHELL,
          args = { '-c', ... },
          enable_recording = true,
        })
        local res, exitcode = job:sync()
        if not exitcode == 0 or #res == 0 then
          error(string.format('exec "%s" failed', ...))
        end
        return res
      end, {}, { user_args = { command } })
    end,
    -- condition helpers
    cond = {
      ts = function(capture)
        return function()
          return vim.tbl_contains(vim.treesitter.get_captures_at_cursor(), capture)
        end
      end,
    },
  }),
})

-- snippet loaders
require('luasnip.loaders.from_lua').lazy_load()
require('luasnip.loaders.from_vscode').lazy_load({ include = {} })

-- keymaps
vim.keymap.set({ 'i', 's' }, '<c-j>', function()
  return vim.snippet.active({ direction = 1 }) and vim.snippet.jump(1)
end, { silent = true, desc = 'snippet: jump next' })

vim.keymap.set({ 'i', 's' }, '<c-k>', function()
  return vim.snippet.active({ direction = -1 }) and vim.snippet.jump(-1)
end, { silent = true, desc = 'snippet: jump prev' })

vim.keymap.set({ 'i', 's' }, '<c-n>', function()
  if ls.choice_active() then
    ls.change_choice(1)
  end
end, { silent = true, desc = 'snippet: next choice' })

vim.keymap.set({ 'i', 's' }, '<c-p>', function()
  if ls.choice_active() then
    ls.change_choice(-1)
  end
end, { silent = true, desc = 'snippet: prev choice' })

-- usercmds
vim.api.nvim_create_user_command('EditSnippets', require('luasnip.loaders').edit_snippet_files, {})

-- autocmds
-- vim.api.nvim_create_autocmd('User', {
--   pattern = 'LuasnipChoiceNodeEnter',
--   callback = function()
--     vim.schedule(function()
--       assert(ls.session.active_choice_nodes[vim.api.nvim_get_current_buf()], 'No active choiceNode')
--       vim.ui.select(
--         ls.get_current_choices(),
--         -- TODO: patch luasnip.extras.select_choice to fix missing prompt
--         { prompt = 'LuaSnip: choice node', kind = 'luasnip' },
--         function(_, idx)
--           if not idx then
--             return
--           end
--           -- feed+immediately execute i to enter INSERT after vim.ui.input closes.
--           vim.api.nvim_feedkeys('i', 'x', false)
--           ls.set_choice(idx)
--           ls.unlink_current()
--         end
--       )
--     end)
--   end,
-- })

-- unlink luasnip session on <esc>
vim.api.nvim_create_autocmd('ModeChanged', {
  pattern = '*',
  callback = function()
    if ((vim.v.event.old_mode == 's' and vim.v.event.new_mode == 'n') or vim.v.event.old_mode == 'i')
        and ls.session.current_nodes[vim.api.nvim_get_current_buf()]
        and not ls.session.jump_active
        and not require("blink.cmp").is_visible()
    then
      ls.unlink_current()
    end
  end
})

-- attach to builtin snippet hooks
vim.snippet.expand = ls.lsp_expand
vim.snippet.active = function(filter)
  filter = filter or {}
  filter.direction = filter.direction or 1
  if filter.direction == 1 then
    return ls.expand_or_jumpable()
  else
    return ls.jumpable(filter.direction)
  end
end
vim.snippet.jump = function(direction)
  if direction == 1 then
    if ls.expandable() then
      return ls.expand_or_jump()
    else
      return ls.jumpable(1) and ls.jump(1)
    end
  else
    return ls.jumpable(-1) and ls.jump(-1)
  end
end
vim.snippet.stop = ls.unlink_current