local api = vim.api
local icons = require "nvim-tree.renderer.icons"

local M = {}

local function get_color_from_hl(hl_name, fallback)
  local id = vim.api.nvim_get_hl_id_by_name(hl_name)
  if not id then
    return fallback
  end

  local foreground = vim.fn.synIDattr(vim.fn.synIDtrans(id), "fg")
  if not foreground or foreground == "" then
    return fallback
  end

  return foreground
end

local function get_colors()
  return {
    red = vim.g.terminal_color_1 or get_color_from_hl("Keyword", "Red"),
    green = vim.g.terminal_color_2 or get_color_from_hl("Character", "Green"),
    yellow = vim.g.terminal_color_3 or get_color_from_hl("PreProc", "Yellow"),
    blue = vim.g.terminal_color_4 or get_color_from_hl("Include", "Blue"),
    purple = vim.g.terminal_color_5 or get_color_from_hl("Define", "Purple"),
    cyan = vim.g.terminal_color_6 or get_color_from_hl("Conditional", "Cyan"),
    dark_red = vim.g.terminal_color_9 or get_color_from_hl("Keyword", "DarkRed"),
    orange = vim.g.terminal_color_11 or get_color_from_hl("Number", "Orange"),
  }
end

local function get_hl_groups()
  local colors = get_colors()

  return {
    IndentMarker = { fg = "#8094b4" },
    Symlink = { gui = "bold", fg = colors.cyan },
    FolderIcon = { fg = "#8094b4" },
    RootFolder = { fg = colors.purple },

    ExecFile = { gui = "bold", fg = colors.green },
    SpecialFile = { gui = "bold,underline", fg = colors.yellow },
    ImageFile = { gui = "bold", fg = colors.purple },
    OpenedFile = { gui = "bold", fg = colors.green },

    GitDirty = { fg = colors.dark_red },
    GitDeleted = { fg = colors.dark_red },
    GitStaged = { fg = colors.green },
    GitMerge = { fg = colors.orange },
    GitRenamed = { fg = colors.purple },
    GitNew = { fg = colors.yellow },

    WindowPicker = { gui = "bold", fg = "#ededed", bg = "#4493c8" },
  }
end

local function get_links()
  return {
    FolderName = "Directory",
    EmptyFolderName = "Directory",
    OpenedFolderName = "Directory",
    Normal = "Normal",
    NormalNC = "NvimTreeNormal",
    EndOfBuffer = "EndOfBuffer",
    CursorLine = "CursorLine",
    VertSplit = "VertSplit",
    CursorColumn = "CursorColumn",
    FileDirty = "NvimTreeGitDirty",
    FileNew = "NvimTreeGitNew",
    FileRenamed = "NvimTreeGitRenamed",
    FileMerge = "NvimTreeGitMerge",
    FileStaged = "NvimTreeGitStaged",
    FileDeleted = "NvimTreeGitDeleted",
    Popup = "Normal",
    GitIgnored = "Comment",
    StatusLine = "StatusLine",
    StatusLineNC = "StatusLineNC",
    SignColumn = "NvimTreeNormal",
  }
end

function M.setup()
  if icons.get_config().show_file_icon and icons.get_config().has_devicons then
    require("nvim-web-devicons").setup()
  end
  local higlight_groups = get_hl_groups()
  for k, d in pairs(higlight_groups) do
    local gui = d.gui and " gui=" .. d.gui or ""
    local fg = d.fg and " guifg=" .. d.fg or ""
    local bg = d.bg and " guibg=" .. d.bg or ""
    api.nvim_command("hi def NvimTree" .. k .. gui .. fg .. bg)
  end

  local links = get_links()
  for k, d in pairs(links) do
    api.nvim_command("hi def link NvimTree" .. k .. " " .. d)
  end
end

return M