local fn = vim.fn
local api = vim.api
local lsp = vim.lsp

local utils = require("utils")

local custom_attach = function(client, bufnr)
  -- Mappings.
  local opts = { silent = true, buffer = bufnr }
  vim.keymap.set("n", "gd", vim.lsp.buf.definition, opts)
  vim.keymap.set("n", "<C-]>", vim.lsp.buf.definition, opts)
  vim.keymap.set("n", "K", vim.lsp.buf.hover, opts)
  vim.keymap.set("n", "<C-k>", vim.lsp.buf.signature_help, opts)
  vim.keymap.set("n", "<space>wa", vim.lsp.buf.add_workspace_folder, opts)
  vim.keymap.set("n", "<space>wr", vim.lsp.buf.remove_workspace_folder, opts)
  vim.keymap.set("n", "<space>wl", function() print(vim.inspect(vim.lsp.buf.list_workspace_folders())) end, opts)
  vim.keymap.set("n", "<space>rn", vim.lsp.buf.rename, opts)
  vim.keymap.set("n", "gr", vim.lsp.buf.references, opts)
  vim.keymap.set("n", "[d", vim.diagnostic.goto_prev, opts)
  vim.keymap.set("n", "]d", vim.diagnostic.goto_next, opts)
  vim.keymap.set("n", "<space>q", function() vim.diagnostic.setqflist({open = true}) end, opts)
  vim.keymap.set("n", "<space>ca", vim.lsp.buf.code_action, opts)

  vim.api.nvim_create_autocmd("CursorHold", {
    buffer=bufnr,
    callback = function()
      local opts = {
        focusable = false,
        close_events = { "BufLeave", "CursorMoved", "InsertEnter", "FocusLost" },
        border = 'rounded',
        source = 'always',  -- show source in diagnostic popup window
        prefix = ' '
      }

      if not vim.b.diagnostics_pos then
        vim.b.diagnostics_pos = { nil, nil }
      end

      local cursor_pos = vim.api.nvim_win_get_cursor(0)
      if (cursor_pos[1] ~= vim.b.diagnostics_pos[1] or cursor_pos[2] ~= vim.b.diagnostics_pos[2]) and
        #vim.diagnostic.get() > 0
      then
          vim.diagnostic.open_float(nil, opts)
      end

      vim.b.diagnostics_pos = cursor_pos
    end
  })

  -- Set some key bindings conditional on server capabilities
  if client.resolved_capabilities.document_formatting then
    vim.keymap.set("n", "<space>f", vim.lsp.buf.formatting_sync, opts)
  end
  if client.resolved_capabilities.document_range_formatting then
    vim.keymap.set("x", "<space>f", vim.lsp.buf.range_formatting, opts)
  end

  -- The blow command will highlight the current variable and its usages in the buffer.
  if client.resolved_capabilities.document_highlight then
    vim.cmd([[
      hi! link LspReferenceRead Visual
      hi! link LspReferenceText Visual
      hi! link LspReferenceWrite Visual
      augroup lsp_document_highlight
        autocmd! * <buffer>
        autocmd CursorHold <buffer> lua vim.lsp.buf.document_highlight()
        autocmd CursorMoved <buffer> lua vim.lsp.buf.clear_references()
      augroup END
    ]])
  end

  if vim.g.logging_level == 'debug' then
    local msg = string.format("Language server %s started!", client.name)
    vim.notify(msg, 'info', {title = 'Nvim-config'})
  end
end

local capabilities = lsp.protocol.make_client_capabilities()
capabilities = require('cmp_nvim_lsp').update_capabilities(capabilities)
capabilities.textDocument.completion.completionItem.snippetSupport = true

local lspconfig = require("lspconfig")

if utils.executable('pylsp') then
  lspconfig.pylsp.setup({
    on_attach = custom_attach,
    settings = {
      pylsp = {
        plugins = {
          pylint = { enabled = true, executable = "pylint" },
          pyflakes = { enabled = false },
          pycodestyle = { enabled = false },
          jedi_completion = { fuzzy = true },
          pyls_isort = { enabled = true },
          pylsp_mypy = { enabled = true },
        },
      },
    },
    flags = {
      debounce_text_changes = 200,
    },
    capabilities = capabilities,
  })
else
  vim.notify("pylsp not found!", 'warn', {title = 'Nvim-config'})
end

-- if utils.executable('pyright') then
--   lspconfig.pyright.setup{
--     on_attach = custom_attach,
--     capabilities = capabilities
--   }
-- else
--   vim.notify("pyright not found!", 'warn', {title = 'Nvim-config'})
-- end

if utils.executable('clangd') then
  lspconfig.clangd.setup({
    on_attach = custom_attach,
    capabilities = capabilities,
    filetypes = { "c", "cpp", "cc" },
    flags = {
      debounce_text_changes = 500,
    },
  })
else
  vim.notify("clangd not found!", 'warn', {title = 'Nvim-config'})
end

-- set up vim-language-server
if utils.executable('vim-language-server') then
  lspconfig.vimls.setup({
    on_attach = custom_attach,
    flags = {
      debounce_text_changes = 500,
    },
    capabilities = capabilities,
  })
else
  vim.notify("vim-language-server not found!", 'warn', {title = 'Nvim-config'})
end

-- set up bash-language-server
if utils.executable('bash-language-server') then
  lspconfig.bashls.setup({
    on_attach = custom_attach,
    capabilities = capabilities,
  })
end

local sumneko_binary_path = fn.exepath("lua-language-server")
if vim.g.is_mac or vim.g.is_linux and sumneko_binary_path ~= "" then
  local sumneko_root_path = fn.fnamemodify(sumneko_binary_path, ":h:h:h")

  local runtime_path = vim.split(package.path, ";")
  table.insert(runtime_path, "lua/?.lua")
  table.insert(runtime_path, "lua/?/init.lua")

  lspconfig.sumneko_lua.setup({
    on_attach = custom_attach,
    cmd = { sumneko_binary_path, "-E", sumneko_root_path .. "/main.lua" },
    settings = {
      Lua = {
        runtime = {
          -- Tell the language server which version of Lua you're using (most likely LuaJIT in the case of Neovim)
          version = "LuaJIT",
          -- Setup your lua path
          path = runtime_path,
        },
        diagnostics = {
          -- Get the language server to recognize the `vim` global
          globals = { "vim" },
        },
        workspace = {
          -- Make the server aware of Neovim runtime files
          library = api.nvim_get_runtime_file("", true),
        },
        -- Do not send telemetry data containing a randomized but unique identifier
        telemetry = {
          enable = false,
        },
      },
    },
    capabilities = capabilities,
  })
end

-- Change diagnostic signs.
fn.sign_define("DiagnosticSignError", { text = "✗", texthl = "DiagnosticSignError" })
fn.sign_define("DiagnosticSignWarn", { text = "!", texthl = "DiagnosticSignWarn" })
fn.sign_define("DiagnosticSignInformation", { text = "", texthl = "DiagnosticSignInfo" })
fn.sign_define("DiagnosticSignHint", { text = "", texthl = "DiagnosticSignHint" })

-- global config for diagnostic
vim.diagnostic.config({
  underline = false,
  virtual_text = false,
  signs = true,
  severity_sort = true,
})

-- lsp.handlers["textDocument/publishDiagnostics"] = lsp.with(lsp.diagnostic.on_publish_diagnostics, {
--   underline = false,
--   virtual_text = false,
--   signs = true,
--   update_in_insert = false,
-- })

-- Change border of documentation hover window, See https://github.com/neovim/neovim/pull/13998.
lsp.handlers["textDocument/hover"] = lsp.with(vim.lsp.handlers.hover, {
  border = "rounded",
})