local M = {}
local ListView = require "guihua.listview"
local TextView = require "guihua.textview"
local util = require "navigator.util"
local log = require"navigator.util".log
local trace = require"navigator.util".trace
local api = vim.api

local top_center = require"guihua.location".top_center

local path_sep = require"navigator.util".path_sep()
local path_cur = require"navigator.util".path_cur()
function M._preview_location(opts) -- location, width, pos_x, pos_y
  local uri = opts.uri
  if uri == nil then
    log("invalid/nil uri ")
    return
  end
  local bufnr = vim.uri_to_bufnr(uri)
  if not api.nvim_buf_is_loaded(bufnr) then
    vim.fn.bufload(bufnr)
  end
  --

  local display_range = opts.location.range
  -- if range.start == nil then
  --   print("error invalid range")
  --   return
  -- end
  -- if range.start.line == nil then
  --   range.start.line = range["end"].line - 1
  --   opts.lnum = range["end"].line + 1
  --   log(opts)
  -- end
  -- if range["end"].line == nil then
  --   range["end"].line = range.start.line + 1
  --   opts.lnum = range.start.line + 1
  --   log(opts)
  -- end
  -- TODO: preview height
  -- local contents = api.nvim_buf_get_lines(bufnr, range.start.line, range["end"].line, false)
  --
  local syntax = api.nvim_buf_get_option(bufnr, "ft")
  if syntax == nil or #syntax < 1 then
    syntax = "c"
  end

  -- trace(syntax, contents)
  local win_opts = {
    syntax = syntax,
    width = opts.width,
    height = display_range['end'].line - display_range.start.line + 1,
    preview_height = opts.height or opts.preview_height,
    pos_x = opts.offset_x,
    pos_y = opts.offset_y,
    range = opts.range,
    display_range = display_range,
    uri = uri,
    allow_edit = opts.enable_edit
  }

  if _NgConfigValues.external then
    win_opts.external = true
    win_opts.relative = nil
  end
  -- win_opts.items = contents
  win_opts.hl_line = opts.lnum - display_range.start.line
  if win_opts.hl_line < 0 then
    win_opts.hl_line = 1
  end
  trace(opts.lnum, opts.range.start.line, win_opts.hl_line)
  log(win_opts)
  local w = TextView:new({
    loc = "offset_center",
    rect = {
      height = win_opts.height, -- opts.preview_heigh or 12, -- TODO 12
      width = win_opts.width,
      pos_x = win_opts.pos_x,
      pos_y = win_opts.pos_y
    },
    list_view_height = win_opts.height,
    -- data = display_data,
    relative = win_opts.relative,
    -- data = opts.items, -- either items or uri
    uri = win_opts.uri,
    syntax = win_opts.syntax,
    enter = win_opts.enter or false,
    range = win_opts.range,
    border = opts.border,
    display_range = win_opts.display_range,
    hl_line = win_opts.hl_line,
    allow_edit = win_opts.allow_edit,
    external = win_opts.external
  })
  return w
end

function M.preview_uri(opts) -- uri, width, line, col, offset_x, offset_y
  -- local handle = vim.loop.new_async(vim.schedule_wrap(function()
  local line_beg = opts.lnum - 1
  if line_beg >= _NgConfigValues.preview_lines_before then
    line_beg = line_beg - _NgConfigValues.preview_lines_before
  elseif line_beg >= 2 then
    line_beg = line_beg - 2
  end
  local loc = {uri = opts.uri, range = {start = {line = line_beg}}}

  -- TODO: preview height
  loc.range["end"] = {line = opts.lnum + opts.preview_height}
  opts.location = loc

  trace("uri", opts.uri, opts.lnum, opts.location.range.start.line, opts.location.range['end'].line)
  return M._preview_location(opts)
  -- handle:close()
  -- end))
  -- handle:send()
end

function M.new_list_view(opts)
  local config = require("navigator").config_values()

  local items = opts.items
  local data = {}

  local wwidth = api.nvim_get_option("columns")

  local loc = "top_center"

  local mwidth = _NgConfigValues.width
  local width = math.floor(wwidth * mwidth)
  if config.width ~= nil and config.width > 0.3 and config.width < 0.99 then
    width = math.floor(wwidth * config.width)
  end
  width = math.min(120, width, opts.width or 120)
  local wheight = math.floor(
                      1 + api.nvim_get_option("lines") * (_NgConfigValues.height + _NgConfigValues.preview_height))
  local pheight = math.max(_NgConfigValues.preview_lines,
                           math.floor(api.nvim_get_option("lines") * _NgConfigValues.preview_height))
  local prompt = opts.prompt or false
  if opts.rawdata then
    data = items
  else
    trace(items)
    data = require"navigator.render".prepare_for_render(items, opts)
  end

  local border = _NgConfigValues.border or 'shadow'

  if not data or vim.tbl_isempty(data) then
    return
  end

  -- replace
  -- TODO: 10 vimrc opt
  if #data > 10 and opts.prompt == nil then
    loc = "top_center"
    prompt = true
  end

  local lheight = math.min(#data, math.floor(wheight * _NgConfigValues.height))

  local r, _ = top_center(lheight, width)

  local offset_y = r + lheight
  -- style shadow took 1 lines
  if border ~= 'none' then
    if border == 'shadow' then
      offset_y = offset_y + 1
    else
      offset_y = offset_y + 1 -- single?
    end
  end
  -- if border is not set, this should be r+lheigh
  if prompt then
    offset_y = offset_y + 1 -- need to check this out
  end
  local idx = require"guihua.util".fzy_idx
  local transparency = _NgConfigValues.transparency
  if transparency == 100 then
    transparency = nil
  end
  local ext = _NgConfigValues.external
  if ext then
    opts.relative = nil
  end
  return ListView:new({
    loc = loc,
    prompt = prompt,
    relative = opts.relative,
    style = opts.style,
    api = opts.api,
    total = opts.total,
    rect = {height = lheight, width = width, pos_x = 0, pos_y = 0},
    -- preview_height = pheight,
    ft = opts.ft or 'guihua',
    -- data = display_data,
    data = data,
    border = border,
    external = ext,
    on_confirm = opts.on_confirm or function(item, split_opts)
      log(split_opts)
      split_opts = split_opts or {}
      if item.filename ~= nil then
        log("openfile ", item.filename, item.lnum, item.col)
        util.open_file_at(item.filename, item.lnum, item.col, split_opts.split)
      end
    end,
    transparency = transparency,
    on_move = opts.on_move or function(item)
      trace("on move", item)
      trace("on move", item.text or item, item.uri, item.filename)
      -- todo fix
      if item.uri == nil then
        item.uri = "file:///" .. item.filename
      end
      return M.preview_uri({
        uri = item.uri,
        width = width,
        height = lheight, -- this is to cal offset
        preview_height = pheight,
        lnum = item.lnum,
        col = item.col,
        range = item.range,
        offset_x = 0,
        offset_y = offset_y,
        border = border,
        external = ext,
        enable_edit = opts.enable_preview_edit or false
      })
    end
  })
end

return M

-- Doc

--[[
    -- each item should look like this
    -- update if API changes
    {
      call_by = { <table 1> },
      col = 40,
      display_filename = "./curry.js",
      filename = "/Users/username/lsp_test/js/curry.js",
      lnum = 4,
      range = {
        end = {
          character = 46,
          line = 3  -- note: C index
        },
        start = {
          character = 39,
          line = 3
        }
      },
      rpath = "js/curry.js",
      text = "      (sum, element, index) => (sum += element * vector2[index]),",
      uri = "file:///Users/username/lsp_test/js/curry.js"
    }
  --]]

-- on move item:
--[[

 call_by = { {
      kind = " ",
      node_scope = {
        end = {
          character = 1,
          line = 7
        },
        start = {
          character = 0,
          line = 0
        }
      },
      node_text = "curriedDot",
      type = "var"
    } },
  col = 22,
  display_filename = "./curry.js",
  filename = "/Users/username/lsp_test/js/curry.js",
  lnum = 4,
  range = {
    end = {
      character = 26,
      line = 3
    },
    start = {
      character = 21,
      line = 3
    }
  },
  rpath = "js/curry.js",
  text = "    4:        (sum, element, index) => (sum += element * vector     curriedDot()",
  uri = "file:///Users/username/lsp_test/js/curry.js"
--
]]