local log = require"navigator.util".log
local function set_keymap(...) vim.api.nvim_set_keymap(...) end

local event_hdlrs = {
  {ev = "BufWritePre", func = "diagnostic.set_loclist({open_loclist = false})"},
  {ev = "CursorHold", func = "document_highlight()"},
  {ev = "CursorHoldI", func = "document_highlight()"},
  {ev = "CursorMoved", func = "clear_references()"}
}

local key_maps = {
  {key = "gr", func = "references()"}, {mode = "i", key = "<M-k>", func = "signature_help()"},
  {key = "gs", func = "signature_help()"}, {key = "g0", func = "document_symbol()"},
  {key = "gW", func = "workspace_symbol()"}, {key = "<c-]>", func = "definition()"},
  {key = "gD", func = "declaration()"},
  {key = "gp", func = "require('navigator.definition').definition_preview()"},
  {key = "gT", func = "require('navigator.treesitter').buf_ts()"},
  {key = "GT", func = "require('navigator.treesitter').bufs_ts()"}, {key = "K", func = "hover()"},
  {key = "ga", mode = "n", func = "code_action()"},
  {key = "ga", mode = "v", func = "range_code_action()"}, {key = "<Leader>re", func = "rename()"},
  {key = "<Leader>gi", func = "incoming_calls()"}, {key = "<Leader>go", func = "outgoing_calls()"},
  {key = "gi", func = "implementation()"}, {key = "gt", func = "type_definition()"},
  {key = "gL", func = "diagnostic.show_line_diagnostics()"},
  {key = "gG", func = "require('navigator.diagnostics').show_diagnostic()"},
  {key = "]d", func = "diagnostic.goto_next()"}, {key = "[d", func = "diagnostic.goto_prev()"},
  {key = "]r", func = "require('navigator.treesitter').goto_next_usage()"},
  {key = "[r", func = "require('navigator.treesitter').goto_previous_usage()"},
  {key = "<C-LeftMouse>", func = "definition()"}, {key = "g<LeftMouse>", func = "implementation()"}
}

local function set_mapping(user_opts)
  local opts = {noremap = true, silent = true}
  user_opts = user_opts or {}

  local user_key = user_opts.keymaps or {}
  local bufnr = user_opts.bufnr or 0

  local function buf_set_keymap(...) vim.api.nvim_buf_set_keymap(bufnr, ...) end

  -- local function buf_set_option(...)
  --   vim.api.nvim_buf_set_option(bufnr, ...)
  -- end
  for _, v in pairs(user_key) do
    local exists = false
    for _, default in pairs(key_maps) do
      if v.func == default.func then
        default.key, exists = v.key, true
        break
      end
    end
    if not exists then table.insert(key_maps, v) end
  end

  -- local key_opts = {vim.tbl_deep_extend("force", key_maps, unpack(result))}
  for _, value in pairs(key_maps) do
    local f = "<Cmd>lua vim.lsp.buf." .. value.func .. "<CR>"
    if string.find(value.func, "require") then
      f = "<Cmd>lua " .. value.func .. "<CR>"
    elseif string.find(value.func, "diagnostic") then
      f = "<Cmd>lua vim.lsp." .. value.func .. "<CR>"
    end
    local k = value.key
    local m = value.mode or "n"
    buf_set_keymap(m, k, f, opts)
  end

  -- format setup

  local range_fmt = false
  local doc_fmt = false
  for _, value in pairs(vim.lsp.buf_get_clients(0)) do
    if value == nil or value.resolved_capabilities == nil then return end
    if value.resolved_capabilities.document_formatting then doc_fmt = true end
    if value.resolved_capabilities.document_range_formatting then range_fmt = true end
  end

  -- if user_opts.cap.document_formatting then
  if doc_fmt then
    buf_set_keymap("n", "<space>ff", "<cmd>lua vim.lsp.buf.formatting()<CR>", opts)
    vim.cmd([[autocmd BufWritePre <buffer> lua vim.lsp.buf.formatting()]])
  end
  -- if user_opts.cap.document_range_formatting then
  if range_fmt then
    buf_set_keymap("v", "<space>ff", "<cmd>lua vim.lsp.buf.range_formatting()<CR>", opts)
  end
end

local function set_event_handler(user_opts)
  user_opts = user_opts or {}
  local file_types = "c,cpp,h,go,python,vim,sh,javascript,html,css,lua,typescript,rust"
  -- local format_files = "c,cpp,h,go,python,vim,javascript,typescript" --html,css,
  vim.api.nvim_command [[augroup nvim_lsp_autos]]
  vim.api.nvim_command [[autocmd!]]

  for _, value in pairs(event_hdlrs) do
    local f = ""
    if string.find(value.func, "diagnostic") then
      f = "lua vim.lsp." .. value.func
    else
      f = "lua vim.lsp.buf." .. value.func
    end
    local cmd = "autocmd FileType " .. file_types .. " autocmd nvim_lsp_autos " .. value.ev ..
                    " <buffer> silent! " .. f
    vim.api.nvim_command(cmd)
  end
  vim.api.nvim_command([[augroup END]])
end

local M = {}

function M.setup(user_opts)
  user_opts = user_opts or {}
  user_opts.cap = vim.lsp.protocol.make_client_capabilities()

  set_mapping(user_opts)
  set_event_handler(user_opts)
  local cap = user_opts.cap or {}
  if cap.call_hierarchy or cap.callHierarchy then
    vim.lsp.handlers["callHierarchy/incomingCalls"] =
        require"navigator.hierarchy".incoming_calls_handler
    vim.lsp.handlers["callHierarchy/outgoingCalls"] =
        require"navigator.hierarchy".outgoing_calls_handler
  end

  vim.lsp.handlers["textDocument/references"] = require"navigator.reference".reference_handler
  vim.lsp.handlers["textDocument/codeAction"] = require"navigator.codeAction".code_action_handler
  vim.lsp.handlers["textDocument/definition"] = require"navigator.definition".definition_handler

  if cap.declaration then
    vim.lsp.handlers["textDocument/declaration"] = require"navigator.definition".declaration_handler
  end

  vim.lsp.handlers["textDocument/typeDefinition"] =
      require"navigator.definition".typeDefinition_handler
  vim.lsp.handlers["textDocument/implementation"] =
      require"navigator.implementation".implementation_handler

  vim.lsp.handlers["textDocument/documentSymbol"] =
      require"navigator.symbols".document_symbol_handler
  vim.lsp.handlers["workspace/symbol"] = require"navigator.symbols".workspace_symbol_handler
  vim.lsp.handlers["textDocument/publishDiagnostics"] =
      require"navigator.diagnostics".diagnostic_handler

  local hassig, sig = pcall(require, "lsp_signature")
  if not hassig then
    vim.lsp.handlers["textDocument/signatureHelp"] = require"navigator.signature".signature_handler
  end

  -- vim.lsp.handlers["textDocument/hover"]  = require 'navigator.hover'.hover_handler
end

return M