local has_notify, notify = pcall(require, "notify")

local a = vim.api
local uv = vim.loop

local Iterator = require "nvim-tree.iterators.node-iterator"

local M = {
  debouncers = {},
}

M.is_windows = vim.fn.has "win32" == 1 or vim.fn.has "win32unix" == 1

function M.path_to_matching_str(path)
  return path:gsub("(%-)", "(%%-)"):gsub("(%.)", "(%%.)"):gsub("(%_)", "(%%_)")
end

function M.warn(msg)
  vim.schedule(function()
    if has_notify then
      notify(msg, vim.log.levels.WARN, { title = "NvimTree" })
    else
      vim.notify("[NvimTree] " .. msg, vim.log.levels.WARN)
    end
  end)
end

function M.str_find(haystack, needle)
  return vim.fn.stridx(haystack, needle) ~= -1
end

function M.read_file(path)
  local fd = uv.fs_open(path, "r", 438)
  if not fd then
    return ""
  end
  local stat = uv.fs_fstat(fd)
  if not stat then
    return ""
  end
  local data = uv.fs_read(fd, stat.size, 0)
  uv.fs_close(fd)
  return data or ""
end

local path_separator = package.config:sub(1, 1)
function M.path_join(paths)
  return table.concat(vim.tbl_map(M.path_remove_trailing, paths), path_separator)
end

function M.path_split(path)
  return path:gmatch("[^" .. path_separator .. "]+" .. path_separator .. "?")
end

---Get the basename of the given path.
---@param path string
---@return string
function M.path_basename(path)
  path = M.path_remove_trailing(path)
  local i = path:match("^.*()" .. path_separator)
  if not i then
    return path
  end
  return path:sub(i + 1, #path)
end

---Get a path relative to another path.
---@param path string
---@param relative_to string
---@return string
function M.path_relative(path, relative_to)
  local p, _ = path:gsub("^" .. M.path_to_matching_str(M.path_add_trailing(relative_to)), "")
  return p
end

function M.path_add_trailing(path)
  if path:sub(-1) == path_separator then
    return path
  end

  return path .. path_separator
end

function M.path_remove_trailing(path)
  local p, _ = path:gsub(path_separator .. "$", "")
  return p
end

M.path_separator = path_separator

function M.clear_prompt()
  vim.api.nvim_command "normal! :"
end

function M.get_user_input_char()
  local c = vim.fn.getchar()
  while type(c) ~= "number" do
    c = vim.fn.getchar()
  end
  return vim.fn.nr2char(c)
end

-- get the node and index of the node from the tree that matches the predicate.
-- The explored nodes are those displayed on the view.
-- @param nodes list of node
-- @param fn    function(node): boolean
function M.find_node(nodes, fn)
  local node, i = Iterator.builder(nodes)
    :matcher(fn)
    :recursor(function(node)
      return node.open and #node.nodes > 0 and node.nodes
    end)
    :iterate()
  i = require("nvim-tree.view").is_root_folder_visible() and i or i - 1
  i = require("nvim-tree.live-filter").filter and i + 1 or i
  return node, i
end

-- get the node in the tree state depending on the absolute path of the node
-- (grouped or hidden too)
function M.get_node_from_path(path)
  local explorer = require("nvim-tree.core").get_explorer()
  if explorer.absolute_path == path then
    return explorer
  end

  return Iterator.builder(explorer.nodes)
    :hidden()
    :matcher(function(node)
      return node.absolute_path == path or node.link_to == path
    end)
    :recursor(function(node)
      if node.group_next then
        return { node.group_next }
      end
      if node.nodes then
        return node.nodes
      end
    end)
    :iterate()
end

-- get the highest parent of grouped nodes
function M.get_parent_of_group(node_)
  local node = node_
  while node.parent and node.parent.group_next do
    node = node.parent
  end
  return node
end

-- return visible nodes indexed by line
-- @param nodes_all list of node
-- @param line_start first index
---@return table
function M.get_nodes_by_line(nodes_all, line_start)
  local nodes_by_line = {}
  local line = line_start

  Iterator.builder(nodes_all)
    :applier(function(node)
      nodes_by_line[line] = node
      line = line + 1
    end)
    :recursor(function(node)
      return node.open == true and node.nodes
    end)
    :iterate()

  return nodes_by_line
end

---Matching executable files in Windows.
---@param ext string
---@return boolean
local PATHEXT = vim.env.PATHEXT or ""
local wexe = vim.split(PATHEXT:gsub("%.", ""), ";")
local pathexts = {}
for _, v in pairs(wexe) do
  pathexts[v] = true
end

function M.is_windows_exe(ext)
  return pathexts[ext:upper()]
end

function M.rename_loaded_buffers(old_path, new_path)
  for _, buf in pairs(a.nvim_list_bufs()) do
    if a.nvim_buf_is_loaded(buf) then
      local buf_name = a.nvim_buf_get_name(buf)
      local exact_match = buf_name == old_path
      local child_match = (
        buf_name:sub(1, #old_path) == old_path and buf_name:sub(#old_path + 1, #old_path + 1) == path_separator
      )
      if exact_match or child_match then
        a.nvim_buf_set_name(buf, new_path .. buf_name:sub(#old_path + 1))
        -- to avoid the 'overwrite existing file' error message on write for
        -- normal files
        if a.nvim_buf_get_option(buf, "buftype") == "" then
          a.nvim_buf_call(buf, function()
            vim.cmd "silent! write!"
            vim.cmd "edit"
          end)
        end
      end
    end
  end
end

--- @param path string path to file or directory
--- @return boolean
function M.file_exists(path)
  local _, error = vim.loop.fs_stat(path)
  return error == nil
end

--- @param path string
--- @return string
function M.canonical_path(path)
  if M.is_windows and path:match "^%a:" then
    return path:sub(1, 1):upper() .. path:sub(2)
  end
  return path
end

-- Create empty sub-tables if not present
-- @param tbl to create empty inside of
-- @param path dot separated string of sub-tables
-- @return deepest sub-table
function M.table_create_missing(tbl, path)
  if tbl == nil then
    return nil
  end

  local t = tbl
  for s in string.gmatch(path, "([^%.]+)%.*") do
    if t[s] == nil then
      t[s] = {}
    end
    t = t[s]
  end

  return t
end

-- Move a value from src to dst if value is nil on dst
-- @param src to copy from
-- @param src_path dot separated string of sub-tables
-- @param src_pos value pos
-- @param dst to copy to
-- @param dst_path dot separated string of sub-tables, created when missing
-- @param dst_pos value pos
function M.move_missing_val(src, src_path, src_pos, dst, dst_path, dst_pos)
  local ok, err = pcall(vim.validate, {
    src = { src, "table" },
    src_path = { src_path, "string" },
    src_pos = { src_pos, "string" },
    dst = { dst, "table" },
    dst_path = { dst_path, "string" },
    dst_pos = { dst_pos, "string" },
  })
  if not ok then
    M.warn("move_missing_val: " .. (err or "invalid arguments"))
  end

  for pos in string.gmatch(src_path, "([^%.]+)%.*") do
    if src[pos] and type(src[pos]) == "table" then
      src = src[pos]
    else
      src = nil
      break
    end
  end
  local src_val = src and src[src_pos]
  if src_val == nil then
    return
  end

  dst = M.table_create_missing(dst, dst_path)
  if dst[dst_pos] == nil then
    dst[dst_pos] = src_val
  end

  src[src_pos] = nil
end

function M.format_bytes(bytes)
  local units = { "B", "K", "M", "G", "T" }

  bytes = math.max(bytes, 0)
  local pow = math.floor((bytes and math.log(bytes) or 0) / math.log(1024))
  pow = math.min(pow, #units)

  local value = bytes / (1024 ^ pow)
  value = math.floor((value * 10) + 0.5) / 10

  pow = pow + 1

  return (units[pow] == nil) and (bytes .. "B") or (value .. units[pow])
end

function M.key_by(tbl, key)
  local keyed = {}
  for _, val in ipairs(tbl) do
    keyed[val[key]] = val
  end
  return keyed
end

---Execute callback timeout ms after the lastest invocation with context. Waiting invocations for that context will be discarded. Caller should this ensure that callback performs the same or functionally equivalent actions.
---@param context string identifies the callback to debounce
---@param timeout number ms to wait
---@param callback function to execute on completion
function M.debounce(context, timeout, callback)
  if M.debouncers[context] then
    pcall(uv.close, M.debouncers[context])
  end

  M.debouncers[context] = uv.new_timer()
  M.debouncers[context]:start(
    timeout,
    0,
    vim.schedule_wrap(function()
      M.debouncers[context]:close()
      M.debouncers[context] = nil
      callback()
    end)
  )
end

return M