-- TODO vim.api.nvim_create_autocmd('LspAttach', {
-- 	callback = function(args)
-- 		local client = vim.lsp.get_client_by_id(args.data.client_id)
-- 		local bufnr = args.buf
-- 	end,
-- })

local my_attach = function(client, bufnr)
  if vim.opt.diff:get() then
    vim.notify('not running LSP client in diff mode', vim.log.levels.WARN)
    vim.lsp.stop_client(client)
    return
  end

  local group = vim.api.nvim_create_augroup('LspOnAttach', {})
  vim.api.nvim_create_autocmd('CursorHold', {
    buffer = bufnr,
    group = group,
    callback = function()
      if _G.diagnostic_hidden then
        return
      end
      -- evalutate if there's already a floating preview buffer
      local existing = vim.F.npcall(vim.api.nvim_buf_get_var, bufnr, 'lsp_floating_preview')
      if not existing or not vim.api.nvim_win_is_valid(existing) then
        vim.diagnostic.open_float()
      end
    end,
  })

  require('lsp-status').on_attach(client)
  if client.supports_method('textDocument/documentSymbol') then
    require('nvim-navic').attach(client, bufnr)
    -- require('aerial').on_attach(client, bufnr)
    -- vim.keymap.set('n', 'g0', vim.lsp.buf.document_symbol, {buffer = bufnr})
  end
  if client.supports_method('workspace/symbol') then
    vim.keymap.set(
      'n',
      'gW',
      vim.lsp.buf.workspace_symbol,
      { buffer = bufnr, desc = 'goto symbol' }
    )
    vim.keymap.set(
      'n',
      ';s',
      require('telescope.builtin').lsp_workspace_symbols,
      { desc = 'lsp workspace symbols' }
    )
  end
  if client.supports_method('textDocument/definition') then
    vim.keymap.set(
      'n',
      '<C-]>',
      vim.lsp.buf.definition,
      { buffer = bufnr, desc = 'goto definition' }
    )
    vim.keymap.set('n', 'gd', vim.lsp.buf.definition, { buffer = bufnr, desc = 'goto definition' })
    vim.keymap.set('n', 'gR', vim.lsp.buf.references, { buffer = bufnr, desc = 'goto references' })
    vim.keymap.set(
      'n',
      ';R',
      require('telescope.builtin').lsp_references,
      { desc = 'lsp references' }
    )
  end
  if client.supports_method('textDocument/hover') then
    vim.keymap.set('n', 'K', vim.lsp.buf.hover, { buffer = bufnr, desc = 'hover' })
  end
  if client.supports_method('textDocument/rename') then
    vim.keymap.set('n', 'grr', vim.lsp.buf.rename, { buffer = bufnr, desc = 'rename' })
  end
  if client.supports_method('signatureHelp') then
    vim.keymap.set(
      'n',
      '<c-h>',
      vim.lsp.buf.signature_help,
      { buffer = bufnr, desc = 'signature help' }
    )
  end
  if client.supports_method('textDocument/formatting') then
    -- if client.server_capabilities.documentFormattingProvider then
    vim.api.nvim_set_option_value('formatexpr', 'v:lua.vim.lsp.formatexpr()', { buf = bufnr })
    vim.keymap.set('n', '<leader>f', vim.lsp.buf.format, { buffer = bufnr, desc = 'format' })
    vim.api.nvim_create_autocmd('BufWritePre', {
      buffer = bufnr,
      callback = function()
        vim.cmd.mkview({ bang = true })
        require('internal.lsp').format(vim.fn.expand('<afile>:p'))
      end,
      group = vim.api.nvim_create_augroup('LspAutoFormat', {}),
    })
  end
  if client.supports_method('textDocument/typeDefinition') then
    vim.keymap.set(
      'n',
      'gT',
      vim.lsp.buf.type_definition,
      { buffer = bufnr, desc = 'goto typedef' }
    )
  end
  if client.supports_method('textDocument/declaration') then
    vim.keymap.set(
      'n',
      'gD',
      vim.lsp.buf.declaration,
      { buffer = bufnr, desc = 'goto declaration' }
    )
  end
  if client.supports_method('textDocument/implementation') then
    vim.keymap.set(
      'n',
      'gI',
      vim.lsp.buf.implementation,
      { buffer = bufnr, desc = 'goto implementation' }
    )
  end
  if client.supports_method('textDocument/codeAction') then
    -- vim.keymap.set('n', 'ga', vim.lsp.buf.code_action, { buffer = bufnr, desc = 'code action' })
    vim.keymap.set('n', 'ga', vim.cmd.CodeActionMenu, { buffer = bufnr, desc = 'code action' })
  end
  if client.supports_method('textDocument/documentHighlight') then
    vim.keymap.set(
      'n',
      '<leader>8',
      vim.lsp.buf.document_highlight,
      { buffer = bufnr, desc = 'document highlight' }
    )
    -- vim.keymap.set('n', '', vim.lsp.buf.clear_references, {buffer = bufnr, desc = 'clear references'})
    vim.api.nvim_create_autocmd('CursorMoved', {
      callback = vim.lsp.buf.clear_references,
      buffer = bufnr,
    })
  end
end

local my_exit = function(_, _, _) end

local capabilities = function()
  local caps = vim.lsp.protocol.make_client_capabilities()

  -- enable lsp-based snippets
  caps = vim.tbl_extend('keep', caps or {}, require('cmp_nvim_lsp').default_capabilities())

  -- add window/workDoneProgress capability
  caps = vim.tbl_extend('keep', caps or {}, require('lsp-status').capabilities)
  return caps
end

local servers = {
  clangd = {
    cmd = {
      'clangd',
      '--clang-tidy',
      '--header-insertion=iwyu',
      '--import-insertions',
      '--header-insertion-decorators',
    }
  },
  elixirls = {
    cmd = { 'elixir-ls' },
    settings = {
      elixirLS = {
        dialyzerEnabled = false,
      },
    },
  },
  gopls = {
    settings = {
      gopls = {
        analyses = {
          --  composites = false,
          fieldalignment = true,
          nilness = true,
          shadow = false,
          unusedparams = true,
          unusedwrite = true,
        },
        gofumpt = true,
        -- hoverKind = 'Structured',
      },
    },
  },
  lua_ls = {
    -- cmd = { 'lua-language-server' },
    cmd = { 'luals' }, -- custom firejail-wrapped
    settings = {
      Lua = {
        runtime = {
          version = 'LuaJIT',
          path = vim.split(package.path, ';'),
        },
        diagnostics = {
          globals = {
            '_G',
            'assert',
            'error',
            'os',
            'package',
            'pairs',
            'ipairs',
            'pcall',
            'require',
            'string',
            'table',
            'type',
            'unpack',
            'vim',
            'xpcall',
          },
          neededFileStatus = {
            ['code-style-check'] = 'Any',
          },
        },
        format = {
          enable = true,
          defaultConfig = {
            indent_style = 'space',
            indent_size = '2',
          },
        },
        workspace = {
          -- library = vim.api.nvim_get_runtime_file("", true),
          library = {
            [vim.env.VIMRUNTIME .. '/lua'] = true,
            [vim.env.VIMRUNTIME .. '/lua/vim/lsp'] = true,
            [vim.fn.stdpath('config') .. '/lua'] = true,
          },
        },
        telemetry = {
          enable = false,
        },
      },
    },
  },
  rust_analyzer = {
    -- cmd = { 'env', 'CARGO_TARGET_DIR=/tmp', 'RUST_SRC_PATH=/usr/src/rustlib/library', 'rust-analyzer' },
    settings = {
      ['rust-analyzer'] = {
        checkOnSave = {
          command = { 'cargo', 'clippy' },
        },
      },
    },
  },
  tsserver = {},
  pylsp = {},
  zls = {},
}

local setup = function()
  -- configure floating win handlers
  vim.lsp.handlers['textDocument/hover'] = vim.lsp.with(vim.lsp.handlers.hover, {
    focus = false,
    zindex = 100,
    border = _G.floating_win_border,
  })
  vim.lsp.handlers['textDocument/signature_help'] =
      vim.lsp.with(vim.lsp.handlers.signature_help, { border = _G.floating_win_border })

  local caps = capabilities()
  for server, opts in pairs(servers) do
    if not opts.disabled then
      opts = vim.tbl_extend('error', opts, {
        on_attach = my_attach,
        on_exit = my_exit,
        capabilities = caps,
      })
      -- lsp-status custom handlers
      local ok, lspstatus_ext = pcall(require('lsp-status').extensions[server])
      if ok then
        opts = vim.tbl_extend('error', opts, {
          handlers = lspstatus_ext.setup(),
        })
      end
      require('lspconfig')[server].setup(opts)
    end
  end
end

local format = function(afile)
  if vim.g.nofmt then
    return
  end

  local errhandler = function(err)
    vim.notify('internal.lsp.format: ' .. err, vim.log.levels.ERROR)
    return err
  end

  -- save folds
  pcall(vim.cmd.mkview, { bang = true })

  -- run lsp format
  xpcall(vim.lsp.buf.format, errhandler)

  -- run organize imports for go
  if string.match(afile, '.go$') then
    xpcall(
      vim.lsp.buf.code_action,
      errhandler,
      { context = { only = { 'source.organizeImports' } }, apply = true }
    )
  end

  -- restore folds
  pcall(vim.cmd.silent, { 'loadview', bank = true })

  -- vim.notify('%#MoreMsg#󰃢%#Italic# fmt', vim.log.levels.INFO)
  vim.notify('internal.lsp.format: 󰃢', vim.log.levels.INFO)
end

return {
  my_attach = my_attach,
  my_exit = my_exit,
  capabilities = capabilities,
  setup = setup,
  format = format,
}