/*
  run tests with `nix-build -A neovim.tests`

  The attrset exposes both the wrapped neovim and the associated test for easier debugging

  Here are some common neovim flags used in the tests:
  -e runs neovim in `:h Ex-mode` which returns an exit code != 0 when hitting an error
  -i NONE  gets rid of shada warnings
*/
{
  vimUtils,
  writeText,
  neovim,
  vimPlugins,
  neovimUtils,
  wrapNeovimUnstable,
  neovim-unwrapped,
  fetchFromGitLab,
  runCommandLocal,
  testers,
  pkgs,
}:
let
  inherit (neovimUtils) makeNeovimConfig;

  plugins = with vimPlugins; [
    {
      plugin = vim-obsession;
      config = ''
        map <Leader>$ <Cmd>Obsession<CR>
      '';
    }
  ];

  packagesWithSingleLineConfigs = with vimPlugins; [
    {
      plugin = vim-obsession;
      config = ''map <Leader>$ <Cmd>Obsession<CR>'';
    }
    {
      plugin = trouble-nvim;
      config = ''" placeholder config'';
    }
  ];

  nvimConfSingleLines = makeNeovimConfig {
    plugins = packagesWithSingleLineConfigs;
    customRC = ''
      " just a comment
    '';
  };

  nvimConfNix = makeNeovimConfig {
    inherit plugins;
    customRC = ''
      " just a comment
    '';
  };

  nvim-with-luasnip = wrapNeovim2 "-with-luasnip" (makeNeovimConfig {
    plugins = [
      {
        plugin = vimPlugins.luasnip;
      }
    ];
  });

  # build should fail with a wrong
  nvim-run-failing-check =
    (wrapNeovimUnstable neovim-unwrapped {
      luaRcContent = "this is an invalid lua statement to break the build";
    }).overrideAttrs
      ({
        doCheck = true;
      });

  nvimAutoDisableWrap = makeNeovimConfig { };

  wrapNeovim2 =
    suffix: config:
    wrapNeovimUnstable neovim-unwrapped (
      config
      // {
        extraName = suffix;
      }
    );

  nmt = fetchFromGitLab {
    owner = "rycee";
    repo = "nmt";
    rev = "d2cc8c1042b1c2511f68f40e2790a8c0e29eeb42";
    sha256 = "1ykcvyx82nhdq167kbnpgwkgjib8ii7c92y3427v986n2s5lsskc";
  };

  /*
    neovim-drv must be a wrapped neovim
    - exposes lua config in $luarcGeneric
    - exposes vim config in $vimrcGeneric
  */

  runTest =
    neovim-drv: buildCommand:
    runCommandLocal "test-${neovim-drv.name}"
      ({
        nativeBuildInputs = [ ];
        meta.platforms = neovim-drv.meta.platforms;
      })
      (
        ''
          source ${nmt}/bash-lib/assertions.sh
          vimrc="${writeText "test-${neovim-drv.name}-init.vim" neovim-drv.initRc}"
          luarc="${writeText "test-${neovim-drv.name}-init.lua" neovim-drv.luaRcContent}"
          luarcGeneric="$out/patched.lua"
          vimrcGeneric="$out/patched.vim"
          mkdir $out
          export HOME=$TMPDIR
          ${pkgs.perl}/bin/perl -pe "s|\Q$NIX_STORE\E/[a-z0-9]{32}-|$NIX_STORE/eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee-|g" < "$vimrc" > "$vimrcGeneric"
          ${pkgs.perl}/bin/perl -pe "s|\Q$NIX_STORE\E/[a-z0-9]{32}-|$NIX_STORE/eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee-|g" < "$luarc" > "$luarcGeneric"
        ''
        + buildCommand
      );

  nvim_with_rocks_nvim = (
    wrapNeovimUnstable neovim-unwrapped {
      extraName = "with-rocks-nvim";
      wrapperArgs = "--set NVIM_APPNAME test-rocks-nvim";
      plugins = [ vimPlugins.rocks-nvim ];
    }
  );
in
pkgs.recurseIntoAttrs (rec {

  inherit nmt;

  failed_check = testers.testBuildFailure nvim-run-failing-check;

  vim_empty_config = vimUtils.vimrcFile {
    beforePlugins = "";
    customRC = "";
  };

  ### neovim tests
  ##################
  nvim_with_plugins = wrapNeovim2 "-with-plugins" nvimConfNix;
  nvim_singlelines = wrapNeovim2 "-single-lines" nvimConfSingleLines;

  # test that passthru.initRc hasn't changed
  passthruInitRc = runTest nvim_singlelines ''
    INITRC=${
      pkgs.writeTextFile {
        name = "initrc";
        text = nvim_singlelines.passthru.initRc;
      }
    }
    assertFileContent \
      $INITRC \
      "${./init-single-lines.vim}"
  '';

  # test single line concatenation
  singlelinesconfig = runTest nvim_singlelines ''
    assertFileContains \
      "$luarcGeneric" \
      "vim.cmd.source \"/nix/store/eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee-init.vim"
    assertFileContent \
      "$vimrcGeneric" \
      "${./init-single-lines.vim}"
  '';

  nvim_via_override = neovim.override {
    extraName = "-via-override";
    configure = {
      packages.foo.start = [ vimPlugins.ale ];
      customRC = ''
        :help ale
      '';
    };
  };

  nvim_with_aliases = neovim.override {
    extraName = "-with-aliases";
    vimAlias = true;
    viAlias = true;
  };

  # test it still works with vim-plug
  nvim_with_plug = neovim.override {
    extraName = "-with-plug";
    configure.packages.plugins = with pkgs.vimPlugins; {
      start = [
        (base16-vim.overrideAttrs (old: {
          pname = old.pname + "-unique-for-tests-please-dont-use";
        }))
      ];
    };
    configure.customRC = ''
      color base16-tomorrow-night
      set background=dark
    '';
  };

  run_nvim_with_plug = runTest nvim_with_plug ''
    ${nvim_with_plug}/bin/nvim -V3log.txt -i NONE -c 'color base16-tomorrow-night'  +quit! -e
  '';

  nvim_with_autoconfigure = pkgs.neovim.overrideAttrs (oa: {
    plugins = [
      vimPlugins.unicode-vim
      vimPlugins.fzf-hoogle-vim
    ];
    autoconfigure = true;
    # legacy wrapper sets it to false
    wrapRc = true;
  });

  nvim_with_runtimeDeps = pkgs.neovim.overrideAttrs ({
    plugins = [
      pkgs.vimPlugins.hex-nvim
    ];
    autowrapRuntimeDeps = true;
    # legacy wrapper sets it to false
    wrapRc = true;
  });

  nvim_with_ftplugin =
    let
      # this plugin checks that it's ftplugin/vim.tex is loaded before $VIMRUNTIME/ftplugin/vim.tex
      # $VIMRUNTIME/ftplugin/vim.tex sources $VIMRUNTIME/ftplugin/initex.vim which sets b:did_ftplugin
      # we save b:did_ftplugin's value in a `plugin_was_loaded_too_late` file
      texFtplugin =
        (pkgs.runCommandLocal "tex-ftplugin" { } ''
          mkdir -p $out/ftplugin
          echo 'call system("echo ". exists("b:did_ftplugin") . " > plugin_was_loaded_too_late")' >> $out/ftplugin/tex.vim
          echo ':q!' >> $out/ftplugin/tex.vim
        '')
        // {
          pname = "test-ftplugin";
        };
    in

    neovim.override {
      extraName = "-with-ftplugin";
      configure.packages.plugins = {
        start = [
          texFtplugin
        ];
      };
    };

  # regression test that ftplugin files from plugins are loaded before the ftplugin
  # files from $VIMRUNTIME
  run_nvim_with_ftplugin = runTest nvim_with_ftplugin ''
    echo '\documentclass{article}' > main.tex

    ${nvim_with_ftplugin}/bin/nvim -i NONE -V3log.txt main.tex -c "set ft?" -c quit
    ls -l $TMPDIR
    # check the saved value b:did_ftplugin then our plugin has been loaded instead of neovim's
    result="$(cat plugin_was_loaded_too_late)"
    echo $result
    [ "$result" = 0 ]
  '';

  # Generate a neovim wrapper with only a init.lua and no init.vim file
  nvim_with_only_init_lua = wrapNeovim2 "-only-lua-init-file" {
    luaRcContent = "-- some text";
  };

  # check that we do not generate an init.vim file if it is not needed
  no_init_vim_file = runTest nvim_with_only_init_lua ''
    ${nvim_with_only_init_lua}/bin/nvim -i NONE -e --headless -c 'if len(getscriptinfo({"name":"init.vim"})) == 0 | quit | else | cquit | fi'
    # This does now work because the lua file is sourced via loadfile() which
    # does not add the file name to :scriptnames and getscriptinfo().
    #${nvim_with_only_init_lua}/bin/nvim -i NONE -e --headless -c 'if len(getscriptinfo({"name":"init.lua"})) == 1 | quit | else | cquit | fi'

    assertFileRegex ${nvim_with_only_init_lua}/bin/nvim 'VIMINIT=.*init.lua'
  '';

  # check that the vim-doc hook correctly generates the tag
  # we know for a fact packer has a doc folder
  checkForTags = vimPlugins.packer-nvim.overrideAttrs (oldAttrs: {
    doInstallCheck = true;
    installCheckPhase = ''
      [ -f $out/doc/tags ]
    '';
  });

  # check that the vim-doc hook correctly generates the tag
  # for neovim packages from luaPackages
  # we know for a fact gitsigns-nvim has a doc folder and comes from luaPackages
  checkForTagsLuaPackages = vimPlugins.gitsigns-nvim.overrideAttrs (oldAttrs: {
    doInstallCheck = true;
    installCheckPhase = ''
      [ -f $out/doc/tags ]
    '';
  });

  nvim_with_gitsigns_plugin = neovim.override {
    extraName = "-with-gitsigns-plugin";
    configure.packages.plugins = {
      start = [
        vimPlugins.gitsigns-nvim
      ];
    };
  };

  checkHelpLuaPackages = runTest nvim_with_gitsigns_plugin ''
    ${nvim_with_gitsigns_plugin}/bin/nvim -i NONE -c 'help gitsigns' +quitall! -e
  '';

  # nixpkgs should detect that no wrapping is necessary
  nvimShouldntWrap = wrapNeovim2 "-should-not-wrap" nvimAutoDisableWrap;

  # this will generate a neovimRc content but we disable wrapping
  nvimDontWrap = wrapNeovim2 "-forced-nowrap" (makeNeovimConfig {
    wrapRc = false;
    customRC = ''
      " this shouldn't trigger the creation of an init.vim
    '';
  });

  force-nowrap = runTest nvimDontWrap ''
    ! grep -F -- ' -u' ${nvimDontWrap}/bin/nvim
  '';

  nvim_via_override-test = runTest nvim_via_override ''
    assertFileContent \
      "$vimrcGeneric" \
      "${./init-override.vim}"
  '';

  checkAliases = runTest nvim_with_aliases ''
    folder=${nvim_with_aliases}/bin
    assertFileIsExecutable "$folder/vi"
    assertFileIsExecutable "$folder/vim"
  '';

  # having no RC generated should autodisable init.vim wrapping
  nvim_autowrap = runTest nvim_via_override ''
    ! grep ${nvimShouldntWrap}/bin/nvim
  '';

  # system remote plugin manifest should be generated, deoplete should be usable
  # without the user having to do `UpdateRemotePlugins`. To test, launch neovim
  # and do `:call deoplete#enable()`. It will print an error if the remote
  # plugin is not registered.
  test_nvim_with_remote_plugin = neovim.override {
    extraName = "-remote";
    configure.packages.foo.start = with vimPlugins; [ deoplete-nvim ];
  };

  nvimWithLuaPackages = wrapNeovim2 "-with-lua-packages" (makeNeovimConfig {
    extraLuaPackages = ps: [ ps.mpack ];
    customRC = ''
      lua require("mpack")
    '';
  });

  nvim_with_lua_packages = runTest nvimWithLuaPackages ''
    ${nvimWithLuaPackages}/bin/nvim -V3log.txt -i NONE --noplugin +quitall! -e
  '';

  # nixpkgs should install optional packages in the opt folder
  nvim_with_opt_plugin = neovim.override {
    extraName = "-with-opt-plugin";
    configure.packages.opt-plugins = with pkgs.vimPlugins; {
      opt = [
        (dashboard-nvim.overrideAttrs (old: {
          pname = old.pname + "-unique-for-tests-please-dont-use-opt";
        }))
      ];
    };
    configure.customRC = ''
      " Load all autoloaded plugins
      packloadall

      " Try to run Dashboard, and throw if it succeeds
      try
        Dashboard
        echo "Dashboard found, throwing error"
        cquit 1
      catch /^Vim\%((\a\+)\)\=:E492/
        echo "Dashboard not found"
      endtry

      " Load Dashboard as an optional
      packadd dashboard-nvim-unique-for-tests-please-dont-use-opt

      " Try to run Dashboard again, and throw if it fails
      let res = exists(':Dashboard')
      if res == 0
        echo "Dashboard not found, throwing error"
        cquit 1
      endif
      cquit 0
    '';
  };

  run_nvim_with_opt_plugin = runTest nvim_with_opt_plugin ''
    ${nvim_with_opt_plugin}/bin/nvim -i NONE +quit! -e
  '';

  autoconfigure = runTest nvim_with_autoconfigure ''
    assertFileContains \
      "$luarc" \
      '${vimPlugins.unicode-vim.passthru.initLua}'
  '';

  autowrap_runtime_deps = runTest nvim_with_runtimeDeps ''
    assertFileContains \
      "${nvim_with_runtimeDeps}/bin/nvim" \
      '${pkgs.xxd}/bin'
  '';

  inherit nvim-with-luasnip;
  # check that bringing in one plugin with lua deps makes those deps visible from wrapper
  # for instance luasnip has a dependency on jsregexp
  can_require_transitive_deps = runTest nvim-with-luasnip ''
    ${nvim-with-luasnip}/bin/nvim -i NONE --cmd "lua require'jsregexp'" -e +quitall!
  '';

  inherit nvim_with_rocks_nvim;
  rocks_install_plenary = runTest nvim_with_rocks_nvim ''
    ${nvim_with_rocks_nvim}/bin/nvim -V3log.txt -i NONE +'Rocks install plenary.nvim' +quit! -e
  '';

  inherit (vimPlugins) corePlugins;
})