vis: move syntax highlighting to pure Lua code

1 files changed, 5 insertions, 183 deletions

diff --git a/view.c b/view.c
index 50b7c8e..ec06b9e 100644
--- a/view.c
+++ b/view.c
@@ -5,7 +5,6 @@
 #include <errno.h>
 #include <regex.h>
 #include <limits.h>
-#include "vis-lua.h"
 #include "view.h"
 #include "text.h"
 #include "text-motions.h"
@@ -88,14 +87,13 @@ struct View {
 	int tabwidth;       /* how many spaces should be used to display a tab character */
 	Cursor *cursors;    /* all cursors currently active */
 	Selection *selections; /* all selected regions */
-	lua_State *lua;     /* lua state used for syntax highlighting */
 	int cursor_generation; /* used to filter out newly created cursors during iteration */
-	char *lexer_name;
 	size_t horizon; /* maximal number of bytes to consider for syntax highlighting
 	                 * before the visible area */
 	bool need_update;   /* whether view has been redrawn */
 	bool large_file;    /* optimize for displaying large files */
 	int colorcolumn;
+	ViewEvent *events;
 };
 
 static const SyntaxSymbol symbols_none[] = {
@@ -124,178 +122,6 @@ static void view_cursors_free(Cursor *c);
 /* set/move current cursor position to a given (line, column) pair */
 static size_t cursor_set(Cursor *cursor, Line *line, int col);
 
-#if !CONFIG_LUA
-
-static void view_syntax_color(View *view) { }
-bool view_syntax_set(View *view, const char *name) { return false; }
-
-#else
-
-static void view_syntax_color(View *view) {
-	lua_State *L = view->lua;
-	if (!L || !view->lexer_name)
-		return;
-	lua_getglobal(L, "vis");
-	lua_getfield(L, -1, "lexers");
-	if (lua_isnil(L, -1))
-		return;
-
-	/* absolute position to start syntax highlighting */
-	const size_t lexer_start = view->start >= view->horizon ?
-		view->start - view->horizon : 0;
-	/* number of bytes used for syntax highlighting before visible are */
-	size_t lexer_before = view->start - lexer_start;
-	/* number of bytes to read in one go */
-	const size_t text_size = lexer_before + (view->end - view->start);
-	/* current buffer to work with */
-	char text[text_size+1];
-	/* bytes to process */
-	const size_t text_len = text_bytes_get(view->text, lexer_start, text_size, text);
-	/* NUL terminate text section */
-	text[text_len] = '\0';
-	if (text_len < lexer_before)
-		lexer_before = text_len;
-
-	lua_getfield(L, -1, "load");
-	lua_pushstring(L, view->lexer_name);
-	lua_pcall(L, 1, 1, 0);
-
-	lua_getfield(L, -1, "_TOKENSTYLES");
-	lua_getfield(L, -2, "lex");
-
-	lua_pushvalue(L, -3); /* lexer obj */
-
-	const char *lex_text = text;
-	if (lexer_start > 0) {
-		/* try to start lexing at a line boundry */
-		/* TODO: start at known state, handle nested lexers */
-		const char *newline = memchr(text, '\n', lexer_before);
-		if (newline)
-			lex_text = newline;
-	}
-
-	lua_pushlstring(L, lex_text, text_len - (lex_text - text));
-	lua_pushinteger(L, 1 /* inital style: whitespace */);
-
-	int token_count;
-
-	if (lua_isfunction(L, -4) &&  !lua_pcall(L, 3, 1, 0) && lua_istable(L, -1) &&
-	   (token_count = lua_objlen(L, -1)) > 0) {
-
-		size_t pos = lexer_before - (lex_text - text);
-		Line *line = view->topline;
-		int col = 0;
-
-		for (int i = 1; i < token_count; i += 2) {
-			lua_rawgeti(L, -1, i);
-			//const char *name = lua_tostring(L, -1);
-			lua_gettable(L, -3); /* _TOKENSTYLES[token] */
-			size_t token_style = lua_tointeger(L, -1);
-			lua_pop(L, 1); /* style */
-			lua_rawgeti(L, -1, i + 1);
-			size_t token_end = lua_tointeger(L, -1) - 1;
-			lua_pop(L, 1); /* pos */
-
-			for (bool token_next = false; line; line = line->next, col = 0) {
-				for (; col < line->width; col++) {
-					if (pos < token_end) {
-						line->cells[col].style = token_style;
-						pos += line->cells[col].len;
-					} else {
-						token_next = true;
-						break;
-					}
-				}
-				if (token_next)
-					break;
-			}
-		}
-		lua_pop(L, 1);
-	}
-
-	lua_pop(L, 3); /* _TOKENSTYLES, language specific lexer, lexers global */
-}
-
-bool view_syntax_set(View *view, const char *name) {
-	lua_State *L = view->lua;
-	if (!L)
-		return name == NULL;
-
-	lua_getglobal(L, "vis");
-	lua_getfield(L, -1, "lexers");
-
-	static const struct {
-		enum UiStyle id;
-		const char *name;
-	} styles[] = {
-		{ UI_STYLE_DEFAULT,        "STYLE_DEFAULT"        },
-		{ UI_STYLE_CURSOR,         "STYLE_CURSOR"         },
-		{ UI_STYLE_CURSOR_PRIMARY, "STYLE_CURSOR_PRIMARY" },
-		{ UI_STYLE_CURSOR_LINE,    "STYLE_CURSOR_LINE"    },
-		{ UI_STYLE_SELECTION,      "STYLE_SELECTION"      },
-		{ UI_STYLE_LINENUMBER,     "STYLE_LINENUMBER"     },
-		{ UI_STYLE_COLOR_COLUMN,   "STYLE_COLOR_COLUMN"   },
-	};
-
-	for (size_t i = 0; i < LENGTH(styles); i++) {
-		lua_getfield(L, -1, styles[i].name);
-		view->ui->syntax_style(view->ui, styles[i].id, lua_tostring(L, -1));
-		lua_pop(L, 1);
-	}
-
-	if (!name) {
-		free(view->lexer_name);
-		view->lexer_name = NULL;
-		return true;
-	}
-
-	/* Try to load the specified lexer and parse its token styles.
-	 * Roughly equivalent to the following lua code:
-	 *
-	 * lang = vis.lexers.load(name)
-	 * for token_name, id in pairs(lang._TOKENSTYLES) do
-	 * 	ui->syntax_style(id, vis.lexers:get_style(lang, token_name);
-	 */
-	lua_getfield(L, -1, "load");
-	lua_pushstring(L, name);
-
-	if (lua_pcall(L, 1, 1, 0))
-		return false;
-
-	if (!lua_istable(L, -1)) {
-		lua_pop(L, 2);
-		return false;
-	}
-
-	view->lexer_name = strdup(name);
-	/* loop through all _TOKENSTYLES and parse them */
-	lua_getfield(L, -1, "_TOKENSTYLES");
-	lua_pushnil(L); /* first key */
-
-	while (lua_next(L, -2)) {
-		size_t id = lua_tointeger(L, -1);
-		//const char *name = lua_tostring(L, -2);
-		lua_pop(L, 1); /* remove value (=id), keep key (=name) */
-		lua_getfield(L, -4, "get_style");
-		lua_pushvalue(L, -5); /* lexer */
-		lua_pushvalue(L, -5); /* lang */
-		lua_pushvalue(L, -4); /* token_name */
-		if (lua_pcall(L, 3, 1, 0))
-			return false;
-		const char *style = lua_tostring(L, -1);
-		//printf("%s\t%d\t%s\n", name, id, style);
-		view->ui->syntax_style(view->ui, id, style);
-		lua_pop(L, 1); /* style */
-	}
-
-	lua_pop(L, 4); /* _TOKENSTYLES, grammar, lexers, vis */
-
-	return true;
-}
-
-#endif
-
-
 void view_tabwidth_set(View *view, int tabwidth) {
 	view->tabwidth = tabwidth;
 	view_draw(view);
@@ -615,7 +441,8 @@ void view_update(View *view) {
 	if (!view->need_update)
 		return;
 
-	view_syntax_color(view);
+	if (view->events->highlight)
+		view->events->highlight(view->events->data);
 
 	if (view->colorcolumn > 0) {
 		size_t lineno = 0;
@@ -719,7 +546,6 @@ void view_free(View *view) {
 	while (view->selections)
 		view_selections_free(view->selections);
 	free(view->lines);
-	free(view->lexer_name);
 	free(view);
 }
 
@@ -729,7 +555,7 @@ void view_reload(View *view, Text *text) {
 	view_cursor_to(view, 0);
 }
 
-View *view_new(Text *text, lua_State *lua) {
+View *view_new(Text *text, ViewEvent *events) {
 	if (!text)
 		return NULL;
 	View *view = calloc(1, sizeof(View));
@@ -741,7 +567,6 @@ View *view_new(Text *text, lua_State *lua) {
 	}
 
 	view->text = text;
-	view->lua = lua;
 	view->tabwidth = 8;
 	view->horizon = 1 << 15;
 	view_options_set(view, 0);
@@ -752,6 +577,7 @@ View *view_new(Text *text, lua_State *lua) {
 	}
 
 	view_cursor_to(view, 0);
+	view->events = events;
 
 	return view;
 }
@@ -1003,10 +829,6 @@ void view_scroll_to(View *view, size_t pos) {
 	view_cursors_scroll_to(view->cursor, pos);
 }
 
-const char *view_syntax_get(View *view) {
-	return view->lexer_name;
-}
-
 void view_options_set(View *view, enum UiOption options) {
 	const int mapping[] = {
 		[SYNTAX_SYMBOL_SPACE]    = UI_OPTION_SYMBOL_SPACE,