//: Clean syntax to manipulate and check the screen in scenarios.
//: Instructions 'assume-screen' and 'screen-should-contain' implicitly create
//: a variable called 'screen' that is accessible inside other 'run'
//: instructions in the scenario. 'screen-should-contain' can check unicode
//: characters in the fake screen

:(scenarios run_mu_scenario)
:(scenario screen_in_scenario)
scenario screen-in-scenario [
  assume-screen 5/width, 3/height
  run [
    1:character <- copy 97/a
    screen:address:screen <- print screen:address:screen, 1:character/a
  ]
  screen-should-contain [
  #  01234
    .a    .
    .     .
    .     .
  ]
]

:(scenario screen_in_scenario_unicode)
scenario screen-in-scenario-unicode-color [
  assume-screen 5/width, 3/height
  run [
    1:character <- copy 955/greek-small-lambda
    screen:address:screen <- print screen:address:screen, 1:character/lambda, 1/red
    2:character <- copy 97/a
    screen:address:screen <- print screen:address:screen, 2:character/a
  ]
  screen-should-contain [
  #  01234
    .λa   .
    .     .
    .     .
  ]
]

:(scenario screen_in_scenario_color)
# screen-should-contain can check unicode characters in the fake screen
scenario screen-in-scenario-color [
  assume-screen 5/width, 3/height
  run [
    1:character <- copy 955/greek-small-lambda
    screen:address:screen <- print screen:address:screen, 1:character/lambda, 1/red
    2:character <- copy 97/a
    screen:address:screen <- print screen:address:screen, 2:character/a, 7/white
  ]
  # screen-should-contain shows everything
  screen-should-contain [
  #  01234
    .λa   .
    .     .
    .     .
  ]
  # screen-should-contain-in-color filters out everything except the given
  # color, all you see is the 'a' in white.
  screen-should-contain-in-color 7/white, [
  #  01234
    . a   .
    .     .
    .     .
  ]
  # ..and the λ in red.
  screen-should-contain-in-color 1/red, [
  #  01234
    .λ    .
    .     .
    .     .
  ]
]

:(scenario screen_in_scenario_error)
% Scenario_testing_scenario = true;
% Hide_errors = true;
scenario screen-in-scenario-error [
  assume-screen 5/width, 3/height
  run [
    1:character <- copy 97/a
    screen:address:screen <- print screen:address:screen, 1:character/a
  ]
  screen-should-contain [
  #  01234
    .b    .
    .     .
    .     .
  ]
]
+error: expected screen location (0, 0) to contain 98 ('b') instead of 97 ('a')

:(scenario screen_in_scenario_color_error)
% Scenario_testing_scenario = true;
% Hide_errors = true;
# screen-should-contain can check unicode characters in the fake screen
scenario screen-in-scenario-color [
  assume-screen 5/width, 3/height
  run [
    1:character <- copy 97/a
    screen:address:screen <- print screen:address:screen, 1:character/a, 1/red
  ]
  screen-should-contain-in-color 2/green, [
  #  01234
    .a    .
    .     .
    .     .
  ]
]
+error: expected screen location (0, 0) to be in color 2 instead of 1

//: allow naming just for 'screen'
:(before "End is_special_name Cases")
if (s == "screen") return true;

:(scenarios run)
:(scenario convert_names_does_not_fail_when_mixing_special_names_and_numeric_locations)
% Scenario_testing_scenario = true;
def main [
  screen:number <- copy 1:number
]
-error: mixing variable names and numeric addresses in main
$error: 0
:(scenarios run_mu_scenario)

:(before "End Globals")
// Scenarios may not define default-space, so they should fit within the
// initial area of memory reserved for tests. We'll put the predefined
// variables available to them at the end of that region.
const int Max_variables_in_scenarios = Reserved_for_tests-100;
int Next_predefined_global_for_scenarios = Max_variables_in_scenarios;
:(before "End Setup")
assert(Next_predefined_global_for_scenarios < Reserved_for_tests);
:(after "transform_all()" following "case RUN:")
// There's a restriction on the number of variables 'run' can use, so that
// it can avoid colliding with the dynamic allocator in case it doesn't
// initialize a default-space.
assert(Name[tmp_recipe.at(0)][""] < Max_variables_in_scenarios);

:(before "End Globals")
// Scenario Globals.
const int SCREEN = Next_predefined_global_for_scenarios++;
// End Scenario Globals.
:(before "End Special Scenario Variable Names(r)")
Name[r]["screen"] = SCREEN;

:(before "End Rewrite Instruction(curr, recipe result)")
// rewrite `assume-screen width, height` to
// `screen:address:screen <- new-fake-screen width, height`
if (curr.name == "assume-screen") {
  curr.name = "new-fake-screen";
  assert(curr.products.empty());
  curr.products.push_back(reagent("screen:address:screen"));
  curr.products.at(0).set_value(SCREEN);
}

//: screen-should-contain is a regular instruction
:(before "End Primitive Recipe Declarations")
SCREEN_SHOULD_CONTAIN,
:(before "End Primitive Recipe Numbers")
put(Recipe_ordinal, "screen-should-contain", SCREEN_SHOULD_CONTAIN);
:(before "End Primitive Recipe Checks")
case SCREEN_SHOULD_CONTAIN: {
  break;
}
:(before "End Primitive Recipe Implementations")
case SCREEN_SHOULD_CONTAIN: {
  if (!Passed) break;
  assert(scalar(ingredients.at(0)));
  check_screen(current_instruction().ingredients.at(0).name, -1);
  break;
}

:(before "End Primitive Recipe Declarations")
SCREEN_SHOULD_CONTAIN_IN_COLOR,
:(before "End Primitive Recipe Numbers")
put(Recipe_ordinal, "screen-should-contain-in-color", SCREEN_SHOULD_CONTAIN_IN_COLOR);
:(before "End Primitive Recipe Checks")
case SCREEN_SHOULD_CONTAIN_IN_COLOR: {
  break;
}
:(before "End Primitive Recipe Implementations")
case SCREEN_SHOULD_CONTAIN_IN_COLOR: {
  if (!Passed) break;
  assert(scalar(ingredients.at(0)));
  assert(scalar(ingredients.at(1)));
  check_screen(current_instruction().ingredients.at(1).name, ingredients.at(0).at(0));
  break;
}

:(before "End Types")
// scan an array of characters in a unicode-aware, bounds-checked manner
struct raw_string_stream {
  int index;
  const int max;
  const char* buf;

  raw_string_stream(const string&);
  uint32_t get();  // unicode codepoint
  uint32_t peek();  // unicode codepoint
  bool at_end() const;
  void skip_whitespace_and_comments();
};

:(code)
void check_screen(pre { line-height: 125%; }
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span.linenos { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
td.linenos .special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
span.linenos.special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
.highlight .hll { background-color: #ffffcc }
.highlight .c { color: #888888 } /* Comment */
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.highlight .cp { color: #cc0000; font-weight: bold } /* Comment.Preproc */
.highlight .cpf { color: #888888 } /* Comment.PreprocFile */
.highlight .c1 { color: #888888 } /* Comment.Single */
.highlight .cs { color: #cc0000; font-weight: bold; background-color: #fff0f0 } /* Comment.Special */
.highlight .gd { color: #000000; background-color: #ffdddd } /* Generic.Deleted */
.highlight .ge { font-style: italic } /* Generic.Emph */
.highlight .ges { font-weight: bold; font-style: italic } /* Generic.EmphStrong */
.highlight .gr { color: #aa0000 } /* Generic.Error */
.highlight .gh { color: #333333 } /* Generic.Heading */
.highlight .gi { color: #000000; background-color: #ddffdd } /* Generic.Inserted */
.highlight .go { color: #888888 } /* Generic.Output */
.highlight .gp { color: #555555 } /* Generic.Prompt */
.highlight .gs { font-weight: bold } /* Generic.Strong */
.highlight .gu { color: #666666 } /* Generic.Subheading */
.highlight .gt { color: #aa0000 } /* Generic.Traceback */
.highlight .kc { color: #008800; font-weight: bold } /* Keyword.Constant */
.highlight .kd { color: #008800; font-weight: bold } /* Keyword.Declaration */
.highlight .kn { color: #008800; font-weight: bold } /* Keyword.Namespace */
.highlight .kp { color: #008800 } /* Keyword.Pseudo */
.highlight .kr { color: #008800; font-weight: bold } /* Keyword.Reserved */
.highlight .kt { color: #888888; font-weight: bold } /* Keyword.Type */
.highlight .m { color: #0000DD; font-weight: bold } /* Literal.Number */
.highlight .s { color: #dd2200; background-color: #fff0f0 } /* Literal.String */
.highlight .na { color: #336699 } /* Name.Attribute */
.highlight .nb { color: #003388 } /* Name.Builtin */
.highlight .nc { color: #bb0066; font-weight: bold } /* Name.Class */
.highlight .no { color: #003366; font-weight: bold } /* Name.Constant */
.highlight .nd { color: #555555 } /* Name.Decorator */
.highlight .ne { color: #bb0066; font-weight: bold } /* Name.Exception */
.highlight .nf { color: #0066bb; font-weight: bold } /* Name.Function */
.highlight .nl { color: #336699; font-style: italic } /* Name.Label */
.highlight .nn { color: #bb0066; font-weight: bold } /* Name.Namespace */
.highlight .py { color: #336699; font-weight: bold } /* Name.Property */
.highlight .nt { color: #bb0066; font-weight: bold } /* Name.Tag */
.highlight .nv { color: #336699 } /* Name.Variable */
.highlight .ow { color: #008800 } /* Operator.Word */
.highlight .w { color: #bbbbbb } /* Text.Whitespace */
.highlight .mb { color: #0000DD; font-weight: bold } /* Literal.Number.Bin */
.highlight .mf { color: #0000DD; font-weight: bold } /* Literal.Number.Float */
.highlight .mh { color: #0000DD; font-weight: bold } /* Literal.Number.Hex */
.highlight .mi { color: #0000DD; font-weight: bold } /* Literal.Number.Integer */
.highlight .mo { color: #0000DD; font-weight: bold } /* Literal.Number.Oct */
.highlight .sa { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Affix */
.highlight .sb { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Backtick */
.highlight .sc { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Char */
.highlight .dl { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Delimiter */
.highlight .sd { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Doc */
.highlight .s2 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Double */
.highlight .se { color: #0044dd; background-color: #fff0f0 } /* Literal.String.Escape */
.highlight .sh { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Heredoc */
.highlight .si { color: #3333bb; background-color: #fff0f0 } /* Literal.String.Interpol */
.highlight .sx { color: #22bb22; background-color: #f0fff0 } /* Literal.String.Other */
.highlight .sr { color: #008800; background-color: #fff0ff } /* Literal.String.Regex */
.highlight .s1 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Single */
.highlight .ss { color: #aa6600; background-color: #fff0f0 } /* Literal.String.Symbol */
.highlight .bp { color: #003388 } /* Name.Builtin.Pseudo */
.highlight .fm { color: #0066bb; font-weight: bold } /* Name.Function.Magic */
.highlight .vc { color: #336699 } /* Name.Variable.Class */
.highlight .vg { color: #dd7700 } /* Name.Variable.Global */
.highlight .vi { color: #3333bb } /* Name.Variable.Instance */
.highlight .vm { color: #336699 } /* Name.Variable.Magic */
.highlight .il { color: #0000DD; font-weight: bold } /* Literal.Number.Integer.Long */
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<title>Mu - baremetal/103grapheme.subx</title>
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<a href='https://github.com/akkartik/mu/blob/main/baremetal/103grapheme.subx'>https://github.com/akkartik/mu/blob/main/baremetal/103grapheme.subx</a>
<pre id='vimCodeElement'>
<span id="L1" class="LineNr">  1 </span><span class="subxComment"># Use the built-in font to draw a grapheme to real screen.</span>
<span id="L2" class="LineNr">  2 </span><span class="subxComment">#</span>
<span id="L3" class="LineNr">  3 </span><span class="subxComment"># We need to do this in machine code because Mu doesn't have global variables</span>
<span id="L4" class="LineNr">  4 </span><span class="subxComment"># yet (for the start of video memory).</span>
<span id="L5" class="LineNr">  5 </span><span class="subxComment">#</span>
<span id="L6" class="LineNr">  6 </span><span class="subxComment"># There are uncomfortable assumptions baked in here about english/latin</span>
<span id="L7" class="LineNr">  7 </span><span class="subxComment"># script. We convert the grid of pixels into a fixed-width grid of graphemes,</span>
<span id="L8" class="LineNr">  8 </span><span class="subxComment"># which may not work well with other language families.</span>
<span id="L9" class="LineNr">  9 </span>
<span id="L10" class="LineNr"> 10 </span>== code
<span id="L11" class="LineNr"> 11 </span>
<span id="L12" class="LineNr"> 12 </span><span class="subxComment"># The Mu computer's screen is 1024px wide and 768px tall.</span>
<span id="L13" class="LineNr"> 13 </span><span class="subxComment"># The Mu computer's font is 8px wide and 16px tall.</span>
<span id="L14" class="LineNr"> 14 </span><span class="subxComment"># Therefore 'x' here is in [0, 128), and 'y' is in [0, 48)</span>
<span id="L15" class="LineNr"> 15 </span><span class="subxFunction">draw-grapheme-on-real-screen</span>:  <span class="subxComment"># g: grapheme, x: int, y: int, color: int, background-color: int</span>
<span id="L16" class="LineNr"> 16 </span>    <span class="subxS1Comment"># . prologue</span>
<span id="L17" class="LineNr"> 17 </span>    55/push-ebp
<span id="L18" class="LineNr"> 18 </span>    89/&lt;- %ebp 4/r32/esp
<span id="L19" class