init.lua

-- Install packer
local install_path = vim.fn.stdpath 'data' .. '/site/pack/packer/start/packer.nvim'
local is_bootstrap = false
if vim.fn.empty(vim.fn.glob(install_path)) > 0 then
  is_bootstrap = true
  vim.fn.system { 'git', 'clone', '--depth', '1', 'https://github.com/wbthomason/packer.nvim', install_path }
  vim.cmd [[packadd packer.nvim]]
end


-- For nvim-tree
-- disable netrw at the very start of your init.lua (strongly advised)
vim.g.loaded_netrw = 1
vim.g.loaded_netrwPlugin = 1

vim.opt.termguicolors = true -- set termguicolors to enable highlight groups

require('packer').startup(function(use)
  -- Package manager
  use 'wbthomason/packer.nvim'

  -- TODO: Better icons for nvim-tree
  -- Directory tree in NVIM.
  use {
    'nvim-tree/nvim-tree.lua',
    config = function ()
      require('nvim-tree').setup({
        renderer = {
          icons = {
            show = {
              file = false,
              folder = false
            }
          }
        }
      })
    end
  }

  -- Get pretty colors when running Java commands in Nvim.
  use { 'm00qek/baleia.nvim', tag = 'v1.2.0' }

  use { -- LSP Configuration & Plugins
    'neovim/nvim-lspconfig',
    requires = {
      -- Automatically install LSPs to stdpath for neovim
      'williamboman/mason.nvim',
      'williamboman/mason-lspconfig.nvim',

      -- Useful status updates for LSP
      'j-hui/fidget.nvim',

      -- Additional lua configuration, makes nvim stuff amazing
      'folke/neodev.nvim',
    },
  }

  -- Java support
  use 'mfussenegger/nvim-jdtls'

  use { -- Autocompletion
    'hrsh7th/nvim-cmp',
    requires = { 'hrsh7th/cmp-nvim-lsp', 'L3MON4D3/LuaSnip', 'saadparwaiz1/cmp_luasnip' },
  }

  use { -- Highlight, edit, and navigate code
    'nvim-treesitter/nvim-treesitter',
    run = function()
      pcall(require('nvim-treesitter.install').update { with_sync = true })
    end,
  }

  use { -- Additional text objects via treesitter
    'nvim-treesitter/nvim-treesitter-textobjects',
    after = 'nvim-treesitter',
  }

  -- Git related plugins
  use 'tpope/vim-fugitive'
  use 'tpope/vim-rhubarb'
  use 'lewis6991/gitsigns.nvim'

  use 'navarasu/onedark.nvim' -- Theme inspired by Atom
  use 'nvim-lualine/lualine.nvim' -- Fancier statusline
  use 'lukas-reineke/indent-blankline.nvim' -- Add indentation guides even on blank lines
  use 'numToStr/Comment.nvim' -- "gc" to comment visual regions/lines
  use 'tpope/vim-sleuth' -- Detect tabstop and shiftwidth automatically

  -- Fuzzy Finder (files, lsp, etc)
  use {
    'nvim-telescope/telescope.nvim',
    requires = { 'nvim-lua/plenary.nvim', 'BurntSushi/ripgrep' },
  }

  use {
    "nvim-telescope/telescope-file-browser.nvim",
    requires = { "nvim-telescope/telescope.nvim", "nvim-lua/plenary.nvim" },
    run = function()
    end
  }

  use { 'nvim-telescope/telescope-ui-select.nvim' }

  -- Fuzzy Finder Algorithm which requires local dependencies to be built. Only load if `make` is available
  use { 'nvim-telescope/telescope-fzf-native.nvim', run = 'make', cond = vim.fn.executable 'make' == 1 }

  -- Add custom plugins to packer from ~/.config/nvim/lua/custom/plugins.lua
  local has_plugins, plugins = pcall(require, 'custom.plugins')
  if has_plugins then
    plugins(use)
  end

  if is_bootstrap then
    require('packer').sync()
  end
end)

-- When we are bootstrapping a configuration, it doesn't
-- make sense to execute the rest of the init.lua.
--
-- You'll need to restart nvim, and then it will work.
if is_bootstrap then
  print '=================================='
  print '    Plugins are being installed'
  print '    Wait until Packer completes,'
  print '       then restart nvim'
  print '=================================='
  return
end

-- Automatically source and re-compile packer whenever you save this init.lua
local packer_group = vim.api.nvim_create_augroup('Packer', { clear = true })
vim.api.nvim_create_autocmd('BufWritePost', {
  command = 'source <afile> | silent! LspStop | silent! LspStart | PackerCompile',
  group = packer_group,
  pattern = vim.fn.expand '$MYVIMRC',
})

-- [[ Setting options ]]
-- See `:help vim.o`

-- Set highlight on search
vim.o.hlsearch = false

-- Make line numbers default
vim.wo.number = true

-- Enable mouse mode
vim.o.mouse = 'a'

-- Enable break indent
vim.o.breakindent = true

-- Save undo history
vim.o.undofile = true

-- Case insensitive searching UNLESS /C or capital in search
vim.o.ignorecase = true
vim.o.smartcase = true

-- Decrease update time
vim.o.updatetime = 250
vim.wo.signcolumn = 'yes'

-- Set colorscheme
vim.o.termguicolors = true
vim.cmd [[colorscheme onedark]]

-- Set completeopt to have a better completion experience
vim.o.completeopt = 'menuone,noselect'

-- [[ Basic Keymaps ]]
-- Set <space> as the leader key
-- See `:help mapleader`
--  NOTE: Must happen before plugins are required (otherwise wrong leader will be used)
vim.g.mapleader = ' '
vim.g.maplocalleader = ' '

-- Keymaps for better default experience
-- See `:help vim.keymap.set()`
vim.keymap.set({ 'n', 'v' }, '<Space>', '<Nop>', { silent = true })

-- Remap for dealing with word wrap
-- TODO: Is this wanted?
-- vim.keymap.set('n', 'k', "v:count == 0 ? 'gk' : 'k'", { expr = true, silent = true })
-- vim.keymap.set('n', 'j', "v:count == 0 ? 'gj' : 'j'", { expr = true, silent = true })

-- Smoother and faster scroll
vim.keymap.set('n', '<C-e>', 'j<C-e>', { silent = true })
vim.keymap.set('n', '<C-y>', 'k<C-y>', { silent = true })
vim.keymap.set('n', '<C-p>', '3k3<C-y>', { silent = true })
vim.keymap.set('n', '<C-n>', '3j3<C-e>', { silent = true })

-- [[ Highlight on yank ]]
-- See `:help vim.highlight.on_yank()`
local highlight_group = vim.api.nvim_create_augroup('YankHighlight', { clear = true })
vim.api.nvim_create_autocmd('TextYankPost', {
  callback = function()
    vim.highlight.on_yank()
  end,
  group = highlight_group,
  pattern = '*',
})

-- Set lualine as statusline
-- See `:help lualine.txt`
require('lualine').setup {
  options = {
    globalstatus = true,
    icons_enabled = false,
    theme = 'onedark',
    component_separators = '|',
    section_separators = '',
  },
}

-- Enable Comment.nvim
require('Comment').setup()

-- Enable `lukas-reineke/indent-blankline.nvim`
-- See `:help indent_blankline.txt`
require('ibl').setup()

-- Gitsigns
-- See `:help gitsigns.txt`
require('gitsigns').setup {
  signs = {
    add = { text = '+' },
    change = { text = '~' },
    delete = { text = '_' },
    topdelete = { text = '‾' },
    changedelete = { text = '~' },
  },
}

-- Enable telescope fzf native, if installed
pcall(require('telescope').load_extension, 'fzf')
pcall(require('telescope').load_extension, 'ui-select')
pcall(require("telescope").load_extension, "file_browser")

-- [[ Configure Telescope ]]
-- See `:help telescope` and `:help telescope.setup()`
require('telescope').setup {
  -- extensions = {
  --   file_browser = {
  --     theme = "ivy",
  --     prompt_title = vim.loop.cwd()
  --   }
  -- }
}


-- See `:help telescope.builtin`
vim.keymap.set('n', '<leader>?', require('telescope.builtin').oldfiles, { desc = '[?] Find recently opened files' })
vim.keymap.set('n', '<leader><space>', require('telescope.builtin').buffers, { desc = '[ ] Find existing buffers' })
vim.keymap.set('n', '<leader>/', function()
  -- You can pass additional configuration to telescope to change theme, layout, etc.
  require('telescope.builtin').current_buffer_fuzzy_find(require('telescope.themes').get_dropdown {
    winblend = 10,
    previewer = false,
  })
end, { desc = '[/] Fuzzily search in current buffer]' })

vim.keymap.set('n', '<leader>sf', require('telescope.builtin').find_files, { desc = '[S]earch [F]iles' })
vim.keymap.set('n', '<leader>sh', require('telescope.builtin').help_tags, { desc = '[S]earch [H]elp' })
vim.keymap.set('n', '<leader>sw', require('telescope.builtin').grep_string, { desc = '[S]earch current [W]ord' })
vim.keymap.set('n', '<leader>sg', require('telescope.builtin').live_grep, { desc = '[S]earch by [G]rep' })
vim.keymap.set('n', '<leader>sd', require('telescope.builtin').diagnostics, { desc = '[S]earch [D]iagnostics' })
vim.keymap.set('n', '<leader>sb', require('telescope').extensions.file_browser.file_browser)

-- nvim-tree
-- vim.keymap.set('n', '<leader>t', require('nvim-tree').toggle, { desc = 'Open File[t]ree' })

-- nvim-telescope file browser

-- [[ Configure Treesitter ]]
-- See `:help nvim-treesitter`
require('nvim-treesitter.configs').setup {
  -- Add languages to be installed here that you want installed for treesitter
  ensure_installed = { 'python', 'java', 'lua' },

  highlight = { enable = true },
  indent = { enable = true, disable = { 'python' } },
  incremental_selection = {
    enable = true,
    keymaps = {
      init_selection = '<c-space>',
      node_incremental = '<c-space>',
      scope_incremental = '<c-s>',
      node_decremental = '<c-backspace>',
    },
  },
  textobjects = {
    select = {
      enable = true,
      lookahead = true, -- Automatically jump forward to textobj, similar to targets.vim
      keymaps = {
        -- You can use the capture groups defined in textobjects.scm
        ['aa'] = '@parameter.outer',
        ['ia'] = '@parameter.inner',
        ['af'] = '@function.outer',
        ['if'] = '@function.inner',
        ['ac'] = '@class.outer',
        ['ic'] = '@class.inner',
      },
    },
    move = {
      enable = true,
      set_jumps = true, -- whether to set jumps in the jumplist
      goto_next_start = {
        [']m'] = '@function.outer',
        [']]'] = '@class.outer',
      },
      goto_next_end = {
        [']M'] = '@function.outer',
        [']['] = '@class.outer',
      },
      goto_previous_start = {
        ['[m'] = '@function.outer',
        ['[['] = '@class.outer',
      },
      goto_previous_end = {
        ['[M'] = '@function.outer',
        ['[]'] = '@class.outer',
      },
    },
    swap = {
      enable = true,
      swap_next = {
        ['<leader>a'] = '@parameter.inner',
      },
      swap_previous = {
        ['<leader>A'] = '@parameter.inner',
      },
    },
  },
}

-- Diagnostic keymaps
vim.keymap.set('n', '[d', vim.diagnostic.goto_prev)
vim.keymap.set('n', ']d', vim.diagnostic.goto_next)
vim.keymap.set('n', '<leader>e', vim.diagnostic.open_float)
vim.keymap.set('n', '<leader>q', vim.diagnostic.setloclist)

-- LSP settings.
--  This function gets run when an LSP connects to a particular buffer.
local on_attach = function(_, bufnr)
  -- NOTE: Remember that lua is a real programming language, and as such it is possible
  -- to define small helper and utility functions so you don't have to repeat yourself
  -- many times.
  --
  -- In this case, we create a function that lets us more easily define mappings specific
  -- for LSP related items. It sets the mode, buffer and description for us each time.
  local nmap = function(keys, func, desc)
    if desc then
      desc = 'LSP: ' .. desc
    end

    vim.keymap.set('n', keys, func, { buffer = bufnr, desc = desc })
  end

  nmap('<leader>rn', vim.lsp.buf.rename, '[R]e[n]ame')
  nmap('<leader>ca', vim.lsp.buf.code_action, '[C]ode [A]ction')

  nmap('gd', vim.lsp.buf.definition, '[G]oto [D]efinition')
  nmap('gr', require('telescope.builtin').lsp_references, '[G]oto [R]eferences')
  nmap('gI', vim.lsp.buf.implementation, '[G]oto [I]mplementation')
  nmap('gD', vim.lsp.buf.declaration, '[G]oto [D]eclaration')
  nmap('<leader>D', vim.lsp.buf.type_definition, 'Type [D]efinition')
  nmap('<leader>ds', require('telescope.builtin').lsp_document_symbols, '[D]ocument [S]ymbols')
  nmap('<leader>ws', require('telescope.builtin').lsp_dynamic_workspace_symbols, '[W]orkspace [S]ymbols')

  -- See `:help K` for why this keymap
  nmap('K', vim.lsp.buf.hover, 'Hover Documentation')
  nmap('<C-k>', vim.lsp.buf.signature_help, 'Signature Documentation')

  -- Lesser used LSP functionality
  nmap('gD', vim.lsp.buf.declaration, '[G]oto [D]eclaration')
  nmap('<leader>wa', vim.lsp.buf.add_workspace_folder, '[W]orkspace [A]dd Folder')
  nmap('<leader>wr', vim.lsp.buf.remove_workspace_folder, '[W]orkspace [R]emove Folder')
  nmap('<leader>wl', function()
    print(vim.inspect(vim.lsp.buf.list_workspace_folders()))
  end, '[W]orkspace [L]ist Folders')

  -- Create a command `:Format` local to the LSP buffer
  vim.api.nvim_buf_create_user_command(bufnr, 'Format', function(_)
    vim.lsp.buf.format()
  end, { desc = 'Format current buffer with LSP' })
end

-- Enable the following language servers
--  Feel free to add/remove any LSPs that you want here. They will automatically be installed.
--
--  Add any additional override configuration in the following tables. They will be passed to
--  the `settings` field of the server config. You must look up that documentation yourself.
local servers = {
  -- clangd = {},
  -- gopls = {},
  -- pyright = {},
  -- rust_analyzer = {},
  -- tsserver = {},
}

-- Setup neovim lua configuration
require('neodev').setup()
--
-- nvim-cmp supports additional completion capabilities, so broadcast that to servers
local capabilities = vim.lsp.protocol.make_client_capabilities()
capabilities = require('cmp_nvim_lsp').default_capabilities(capabilities)

-- Setup mason so it can manage external tooling
require('mason').setup()

-- Ensure the servers above are installed
local mason_lspconfig = require 'mason-lspconfig'

mason_lspconfig.setup {
  ensure_installed = vim.tbl_keys(servers),
}

mason_lspconfig.setup_handlers {
  function(server_name)
    require('lspconfig')[server_name].setup {
      capabilities = capabilities,
      on_attach = on_attach,
      settings = servers[server_name],
    }
  end,
}

-- Turn on lsp status information
require('fidget').setup()

-- nvim-cmp setup
local cmp = require 'cmp'
local luasnip = require 'luasnip'

cmp.setup {
  snippet = {
    expand = function(args)
      luasnip.lsp_expand(args.body)
    end,
  },
  mapping = cmp.mapping.preset.insert {
    ['<C-d>'] = cmp.mapping.scroll_docs(-4),
    ['<C-f>'] = cmp.mapping.scroll_docs(4),
    ['<C-Space>'] = cmp.mapping.complete(),
    ['<CR>'] = cmp.mapping.confirm {
      behavior = cmp.ConfirmBehavior.Replace,
      select = true,
    },
    ['<Tab>'] = cmp.mapping(function(fallback)
      if cmp.visible() then
        cmp.select_next_item()
      elseif luasnip.expand_or_jumpable() then
        luasnip.expand_or_jump()
      else
        fallback()
      end
    end, { 'i', 's' }),
    ['<S-Tab>'] = cmp.mapping(function(fallback)
      if cmp.visible() then
        cmp.select_prev_item()
      elseif luasnip.jumpable(-1) then
        luasnip.jump(-1)
      else
        fallback()
      end
    end, { 'i', 's' }),
  },
  sources = {
    { name = 'nvim_lsp' },
    { name = 'luasnip' },
  },
}

local run_and_display_output = function (shell_command)

  local function create_scratch_window()
    -- Create a buffer (listed and scratch mode).
    -- Sets nomodified and nomodeline to true.
    local buf_handle = vim.api.nvim_create_buf(true, true)

    -- Open a window below to compile and show the output.
    -- TODO: Try a more creative way to show the compiler. Maybe a popover? Smaller window?
    vim.cmd.split()

    local window = vim.api.nvim_get_current_win()
    vim.api.nvim_win_set_buf(window, buf_handle)

    vim.keymap.set('n', 'q', function() vim.api.nvim_win_close(window, false) end, { buffer = buf_handle})

    return buf_handle
  end

  local run_java_buffer_handle = create_scratch_window()

  local baleia = require 'baleia'.setup {}

  -- Start the compilation job. Send the output to 
  vim.fn.jobstart(shell_command, {
    --pty = true,
    on_stdout = function (_, data)
      if data then
        -- Are there some edge cases here? Two idea:
        -- - If the shell program doesn't return a newline, will data be emitted to the `on_stdout`
        --   callback?
        -- - If the data _is_ emitted when there is no newline, is this way of doing things correct?
        -- - How will this handle shell commands that rewrite the last line (like a curl progress bar)?.

        --   The reason we overwrite the last line is because a trailing newline will be added
        -- since that newline exists in the output of the shell command. If we don't overwrite the
        -- last line in the buffer, then there will be random gaps in the output.
        local lastline = vim.api.nvim_buf_line_count(run_java_buffer_handle)
        baleia.buf_set_lines(run_java_buffer_handle, lastline - 1, -1, true, data)
      end
    end
  });
end

local function command_runner(shell_arguments_async)
  return function()
    run_and_display_output(shell_arguments_async())
  end
end

local function maven_compile_and_exec()
  local class_name = require('jdtls.util').resolve_classname()
  return {"mvn", "compile", "exec:java", "-Dexec.mainClass=" .. class_name}
end

-- `mvn` must be in your $PATH when `nvim` is started.
vim.keymap.set('n', '<leader>cr', command_runner(maven_compile_and_exec), {desc = "[C]ompile then [R]un your Java code."})
vim.keymap.set('n', '<leader>cc', command_runner(function() return {"mvn", "compile"} end), {desc = "Only [C]ompile your code."})
vim.keymap.set('n', '<leader>cl', command_runner(function() return {"mvn", "clean"} end ), {desc = "Run `mvn` [C]lean"})
vim.keymap.set('n', '<leader>ct', command_runner(function() return {"mvn", "compile", "test"} end ), {desc = "Run `mvn` [C]ompile and [T]est"})


-- The line beneath this is called `modeline`. See `:help modeline`
-- vim: ts=2 sts=2 sw=2 et