From 5fc413c46d83a05778c03dda937b9880c82af32f Mon Sep 17 00:00:00 2001
From: Martin Preuss <martin@aquamaniac.de>
Date: Thu, 23 May 2024 13:34:23 +0200
Subject: [PATCH] reuse code.

---
 src/lib/aqdiagram/draw/context_cairo.c | 405 ++++++++++---------------
 1 file changed, 157 insertions(+), 248 deletions(-)

diff --git a/src/lib/aqdiagram/draw/context_cairo.c b/src/lib/aqdiagram/draw/context_cairo.c
index 8b860cd..73b9faf 100644
--- a/src/lib/aqdiagram/draw/context_cairo.c
+++ b/src/lib/aqdiagram/draw/context_cairo.c
@@ -41,6 +41,13 @@ static int _getTextWidth(AQDG_DRAW_CONTEXT *g, int fontId, const char *text);
 static int _getTextHeight(AQDG_DRAW_CONTEXT *g, int fontId, const char *text);
 static int _finish(AQDG_DRAW_CONTEXT *g);
 
+static AQDG_DRAW_CONTEXT_CAIRO *_ensureFullCairoContext(const AQDG_DRAW_CONTEXT *g);
+static AQDG_DRAW_CONTEXT_CAIRO *_ensureCairoSurface(const AQDG_DRAW_CONTEXT *g);
+
+static void _setColourAndWidthFromPen(cairo_t *cr, const AQDG_DRAW_PEN *pen);
+static void _setDashType(cairo_t *cr, int dashType);
+static void _setFont(cairo_t *cr, AQDG_DRAW_FONT *font);
+
 
 
 /* ------------------------------------------------------------------------------------------------
@@ -238,12 +245,9 @@ int _penCreate(AQDG_DRAW_CONTEXT *g, uint32_t frontColour, int lineWidth, int da
   AQDG_DRAW_CONTEXT_CAIRO *xg;
   AQDG_DRAW_PEN *pen;
 
-  assert(g);
-  xg=GWEN_INHERIT_GETDATA(AQDG_DRAW_CONTEXT, AQDG_DRAW_CONTEXT_CAIRO, g);
-  assert(xg);
-
-  if (xg->surface==NULL) {
-    DBG_ERROR(0, "No surface created");
+  xg=_ensureCairoSurface(g);
+  if (xg==NULL) {
+    DBG_INFO(NULL, "here");
     return GWEN_ERROR_INVALID;
   }
 
@@ -264,12 +268,9 @@ int _penRelease(AQDG_DRAW_CONTEXT *g, int penId)
   AQDG_DRAW_CONTEXT_CAIRO *xg;
   AQDG_DRAW_PEN *pen;
 
-  assert(g);
-  xg=GWEN_INHERIT_GETDATA(AQDG_DRAW_CONTEXT, AQDG_DRAW_CONTEXT_CAIRO, g);
-  assert(xg);
-
-  if (xg->surface==NULL) {
-    DBG_ERROR(0, "No surface created");
+  xg=_ensureCairoSurface(g);
+  if (xg==NULL) {
+    DBG_INFO(NULL, "here");
     return GWEN_ERROR_INVALID;
   }
 
@@ -290,22 +291,10 @@ int _drawLine(AQDG_DRAW_CONTEXT *g, int penId, int xStart, int yStart, int xEnd,
 {
   AQDG_DRAW_CONTEXT_CAIRO *xg;
   AQDG_DRAW_PEN *pen;
-  uint32_t fgCol;
-  double red, green, blue;
-  int i;
-  int dashType;
 
-  assert(g);
-  xg=GWEN_INHERIT_GETDATA(AQDG_DRAW_CONTEXT, AQDG_DRAW_CONTEXT_CAIRO, g);
-  assert(xg);
-
-  if (xg->surface==NULL) {
-    DBG_ERROR(0, "No surface created");
-    return GWEN_ERROR_INVALID;
-  }
-
-  if (xg->cr==NULL) {
-    DBG_ERROR(0, "Graphics context not active, call \"AQDG_Draw_Context_BeginDraw()\" before");
+  xg=_ensureFullCairoContext(g);
+  if (xg==NULL) {
+    DBG_INFO(NULL, "here");
     return GWEN_ERROR_INVALID;
   }
 
@@ -315,40 +304,8 @@ int _drawLine(AQDG_DRAW_CONTEXT *g, int penId, int xStart, int yStart, int xEnd,
     return GWEN_ERROR_NOT_FOUND;
   }
 
-  /*  set foreground color */;
-  fgCol=AQDG_Draw_Pen_GetFrontColour(pen);
-  red=(double)((fgCol>>24) & 0xff)/255.0;
-  green=(double)((fgCol>>16) & 0xff)/255.0;
-  blue=(double)((fgCol>>8) & 0xff)/255.0;
-  cairo_set_source_rgb(xg->cr, red, green, blue);
-
-  /* set line width */
-  i=AQDG_Draw_Pen_GetLineWidth(pen);
-  cairo_set_line_width(xg->cr, i);
-
-  dashType=AQDG_Draw_Pen_GetDashType(pen);
-
-  switch (dashType) {
-  default:
-  case 0:
-    cairo_set_dash(xg->cr, NULL, 0, 0.0);
-    break;
-  case 1:
-    cairo_set_dash(xg->cr, AQDG_Draw_ContextCairo_DashPattern1, 2, 0.0);
-    break;
-  case 2:
-    cairo_set_dash(xg->cr, AQDG_Draw_ContextCairo_DashPattern2, 2, 0.0);
-    break;
-  case 3:
-    cairo_set_dash(xg->cr, AQDG_Draw_ContextCairo_DashPattern3, 2, 0.0);
-    break;
-  case 4:
-    cairo_set_dash(xg->cr, AQDG_Draw_ContextCairo_DashPattern4, 2, 0.0);
-    break;
-  case 5:
-    cairo_set_dash(xg->cr, AQDG_Draw_ContextCairo_DashPattern5, 2, 0.0);
-    break;
-  }
+  _setColourAndWidthFromPen(xg->cr, pen);
+  _setDashType(xg->cr, AQDG_Draw_Pen_GetDashType(pen));
 
   /* draw line from start to end position */
   cairo_move_to(xg->cr, xStart, yStart);
@@ -364,21 +321,10 @@ int _drawRect(AQDG_DRAW_CONTEXT *g, int penId, int x, int y, int w, int h)
 {
   AQDG_DRAW_CONTEXT_CAIRO *xg;
   AQDG_DRAW_PEN *pen;
-  uint32_t fgCol;
-  double red, green, blue;
-  int i;
 
-  assert(g);
-  xg=GWEN_INHERIT_GETDATA(AQDG_DRAW_CONTEXT, AQDG_DRAW_CONTEXT_CAIRO, g);
-  assert(xg);
-
-  if (xg->surface==NULL) {
-    DBG_ERROR(0, "No surface created");
-    return GWEN_ERROR_INVALID;
-  }
-
-  if (xg->cr==NULL) {
-    DBG_INFO(0, "Graphics context not active, call \"AQDG_Draw_Context_BeginDraw()\" before");
+  xg=_ensureFullCairoContext(g);
+  if (xg==NULL) {
+    DBG_INFO(NULL, "here");
     return GWEN_ERROR_INVALID;
   }
 
@@ -388,16 +334,7 @@ int _drawRect(AQDG_DRAW_CONTEXT *g, int penId, int x, int y, int w, int h)
     return GWEN_ERROR_NOT_FOUND;
   }
 
-  /*  set foreground color */;
-  fgCol=AQDG_Draw_Pen_GetFrontColour(pen);
-  red=(double)((fgCol>>24) & 0xff)/255.0;
-  green=(double)((fgCol>>16) & 0xff)/255.0;
-  blue=(double)((fgCol>>8) & 0xff)/255.0;
-  cairo_set_source_rgb(xg->cr, red, green, blue);
-
-  /* set line width */
-  i=AQDG_Draw_Pen_GetLineWidth(pen);
-  cairo_set_line_width(xg->cr, i);
+  _setColourAndWidthFromPen(xg->cr, pen);
 
   cairo_set_dash(xg->cr, NULL, 0, 0.0);
 
@@ -414,21 +351,10 @@ int _drawFilledRect(AQDG_DRAW_CONTEXT *g, int penId, int x, int y, int w, int h)
 {
   AQDG_DRAW_CONTEXT_CAIRO *xg;
   AQDG_DRAW_PEN *pen;
-  uint32_t fgCol;
-  double red, green, blue;
-  int i;
 
-  assert(g);
-  xg=GWEN_INHERIT_GETDATA(AQDG_DRAW_CONTEXT, AQDG_DRAW_CONTEXT_CAIRO, g);
-  assert(xg);
-
-  if (xg->surface==NULL) {
-    DBG_ERROR(0, "No surface created");
-    return GWEN_ERROR_INVALID;
-  }
-
-  if (xg->cr==NULL) {
-    DBG_INFO(0, "Graphics context not active, call \"AQDG_Draw_Context_BeginDraw()\" before");
+  xg=_ensureFullCairoContext(g);
+  if (xg==NULL) {
+    DBG_INFO(NULL, "here");
     return GWEN_ERROR_INVALID;
   }
 
@@ -438,16 +364,7 @@ int _drawFilledRect(AQDG_DRAW_CONTEXT *g, int penId, int x, int y, int w, int h)
     return GWEN_ERROR_NOT_FOUND;
   }
 
-  /*  set foreground color */;
-  fgCol=AQDG_Draw_Pen_GetFrontColour(pen);
-  red=(double)((fgCol>>24) & 0xff)/255.0;
-  green=(double)((fgCol>>16) & 0xff)/255.0;
-  blue=(double)((fgCol>>8) & 0xff)/255.0;
-  cairo_set_source_rgb(xg->cr, red, green, blue);
-
-  /* set line width */
-  i=AQDG_Draw_Pen_GetLineWidth(pen);
-  cairo_set_line_width(xg->cr, i);
+  _setColourAndWidthFromPen(xg->cr, pen);
 
   cairo_set_dash(xg->cr, NULL, 0, 0.0);
 
@@ -466,12 +383,9 @@ int _fontCreate(AQDG_DRAW_CONTEXT *g, const char *face, int fontSize, int fontSl
   AQDG_DRAW_CONTEXT_CAIRO *xg;
   AQDG_DRAW_FONT *font;
 
-  assert(g);
-  xg=GWEN_INHERIT_GETDATA(AQDG_DRAW_CONTEXT, AQDG_DRAW_CONTEXT_CAIRO, g);
-  assert(xg);
-
-  if (xg->surface==NULL) {
-    DBG_ERROR(0, "No surface created");
+  xg=_ensureCairoSurface(g);
+  if (xg==NULL) {
+    DBG_INFO(NULL, "here");
     return GWEN_ERROR_INVALID;
   }
 
@@ -494,12 +408,9 @@ int _fontRelease(AQDG_DRAW_CONTEXT *g, int fontId)
   AQDG_DRAW_CONTEXT_CAIRO *xg;
   AQDG_DRAW_FONT *font;
 
-  assert(g);
-  xg=GWEN_INHERIT_GETDATA(AQDG_DRAW_CONTEXT, AQDG_DRAW_CONTEXT_CAIRO, g);
-  assert(xg);
-
-  if (xg->surface==NULL) {
-    DBG_ERROR(0, "No surface created");
+  xg=_ensureCairoSurface(g);
+  if (xg==NULL) {
+    DBG_INFO(NULL, "here");
     return GWEN_ERROR_INVALID;
   }
 
@@ -520,25 +431,12 @@ int _drawText(AQDG_DRAW_CONTEXT *g, int penId, int fontId, int direction, int x,
 {
   AQDG_DRAW_CONTEXT_CAIRO *xg;
   AQDG_DRAW_FONT *font;
-  int crSlant;
-  int crWeight;
   AQDG_DRAW_PEN *pen;
-  uint32_t fgCol;
-  double red, green, blue;
-  int i;
   cairo_font_extents_t extents;
 
-  assert(g);
-  xg=GWEN_INHERIT_GETDATA(AQDG_DRAW_CONTEXT, AQDG_DRAW_CONTEXT_CAIRO, g);
-  assert(xg);
-
-  if (xg->surface==NULL) {
-    DBG_ERROR(0, "No surface created");
-    return GWEN_ERROR_INVALID;
-  }
-
-  if (xg->cr==NULL) {
-    DBG_INFO(0, "Graphics context not active, call \"AQDG_Draw_Context_BeginDraw()\" before");
+  xg=_ensureFullCairoContext(g);
+  if (xg==NULL) {
+    DBG_INFO(NULL, "here");
     return GWEN_ERROR_INVALID;
   }
 
@@ -549,16 +447,7 @@ int _drawText(AQDG_DRAW_CONTEXT *g, int penId, int fontId, int direction, int x,
     return GWEN_ERROR_NOT_FOUND;
   }
 
-  /*  set foreground color */;
-  fgCol=AQDG_Draw_Pen_GetFrontColour(pen);
-  red=(double)((fgCol>>24) & 0xff)/255.0;
-  green=(double)((fgCol>>16) & 0xff)/255.0;
-  blue=(double)((fgCol>>8) & 0xff)/255.0;
-  cairo_set_source_rgb(xg->cr, red, green, blue);
-
-  /* set line width */
-  i=AQDG_Draw_Pen_GetLineWidth(pen);
-  cairo_set_line_width(xg->cr, i);
+  _setColourAndWidthFromPen(xg->cr, pen);
 
   /* get and handle font */
   font=AQDG_Draw_Font_List_GetById(xg->fontList, fontId);
@@ -566,28 +455,7 @@ int _drawText(AQDG_DRAW_CONTEXT *g, int penId, int fontId, int direction, int x,
     DBG_INFO(0, "Font %d not found", fontId);
     return GWEN_ERROR_NOT_FOUND;
   }
-
-  switch (AQDG_Draw_Font_GetFontSlant(font)) {
-  default:
-  case AQDG_Slant_None:
-    crSlant=CAIRO_FONT_SLANT_NORMAL;
-    break;
-  case AQDG_Slant_Italic:
-    crSlant=CAIRO_FONT_SLANT_ITALIC;
-    break;
-  }
-
-  switch (AQDG_Draw_Font_GetFontWeight(font)) {
-  default:
-  case AQDG_Weight_None:
-    crWeight=CAIRO_FONT_WEIGHT_NORMAL;
-    break;
-  case AQDG_Weight_Bold:
-    crWeight=CAIRO_FONT_WEIGHT_BOLD;
-    break;
-  }
-  cairo_select_font_face(xg->cr, AQDG_Draw_Font_GetFontName(font), crSlant, crWeight);
-  cairo_set_font_size(xg->cr, AQDG_Draw_Font_GetFontSize(font));
+  _setFont(xg->cr, font);
 
   cairo_font_extents(xg->cr, &extents);
 
@@ -604,21 +472,11 @@ int _getTextWidth(AQDG_DRAW_CONTEXT *g, int fontId, const char *text)
 {
   AQDG_DRAW_CONTEXT_CAIRO *xg;
   AQDG_DRAW_FONT *font;
-  int crSlant;
-  int crWeight;
   cairo_text_extents_t extents;
 
-  assert(g);
-  xg=GWEN_INHERIT_GETDATA(AQDG_DRAW_CONTEXT, AQDG_DRAW_CONTEXT_CAIRO, g);
-  assert(xg);
-
-  if (xg->surface==NULL) {
-    DBG_ERROR(0, "No surface created");
-    return GWEN_ERROR_INVALID;
-  }
-
-  if (xg->cr==NULL) {
-    DBG_INFO(0, "Graphics context not active, call \"AQDG_Draw_Context_BeginDraw()\" before");
+  xg=_ensureFullCairoContext(g);
+  if (xg==NULL) {
+    DBG_INFO(NULL, "here");
     return GWEN_ERROR_INVALID;
   }
 
@@ -629,27 +487,7 @@ int _getTextWidth(AQDG_DRAW_CONTEXT *g, int fontId, const char *text)
     return GWEN_ERROR_NOT_FOUND;
   }
 
-  switch (AQDG_Draw_Font_GetFontSlant(font)) {
-  default:
-  case AQDG_Slant_None:
-    crSlant=CAIRO_FONT_SLANT_NORMAL;
-    break;
-  case AQDG_Slant_Italic:
-    crSlant=CAIRO_FONT_SLANT_ITALIC;
-    break;
-  }
-
-  switch (AQDG_Draw_Font_GetFontWeight(font)) {
-  default:
-  case AQDG_Weight_None:
-    crWeight=CAIRO_FONT_WEIGHT_NORMAL;
-    break;
-  case AQDG_Weight_Bold:
-    crWeight=CAIRO_FONT_WEIGHT_BOLD;
-    break;
-  }
-  cairo_select_font_face(xg->cr, AQDG_Draw_Font_GetFontName(font), crSlant, crWeight);
-  cairo_set_font_size(xg->cr, AQDG_Draw_Font_GetFontSize(font));
+  _setFont(xg->cr, font);
 
   cairo_text_extents(xg->cr, text, &extents);
 
@@ -662,21 +500,11 @@ int _getTextHeight(AQDG_DRAW_CONTEXT *g, int fontId, const char *text)
 {
   AQDG_DRAW_CONTEXT_CAIRO *xg;
   AQDG_DRAW_FONT *font;
-  int crSlant;
-  int crWeight;
   cairo_text_extents_t extents;
 
-  assert(g);
-  xg=GWEN_INHERIT_GETDATA(AQDG_DRAW_CONTEXT, AQDG_DRAW_CONTEXT_CAIRO, g);
-  assert(xg);
-
-  if (xg->surface==NULL) {
-    DBG_ERROR(0, "No surface created");
-    return GWEN_ERROR_INVALID;
-  }
-
-  if (xg->cr==NULL) {
-    DBG_INFO(0, "Graphics context not active, call \"AQDG_Draw_Context_BeginDraw()\" before");
+  xg=_ensureFullCairoContext(g);
+  if (xg==NULL) {
+    DBG_INFO(NULL, "here");
     return GWEN_ERROR_INVALID;
   }
 
@@ -687,27 +515,7 @@ int _getTextHeight(AQDG_DRAW_CONTEXT *g, int fontId, const char *text)
     return GWEN_ERROR_NOT_FOUND;
   }
 
-  switch (AQDG_Draw_Font_GetFontSlant(font)) {
-  default:
-  case AQDG_Slant_None:
-    crSlant=CAIRO_FONT_SLANT_NORMAL;
-    break;
-  case AQDG_Slant_Italic:
-    crSlant=CAIRO_FONT_SLANT_ITALIC;
-    break;
-  }
-
-  switch (AQDG_Draw_Font_GetFontWeight(font)) {
-  default:
-  case AQDG_Weight_None:
-    crWeight=CAIRO_FONT_WEIGHT_NORMAL;
-    break;
-  case AQDG_Weight_Bold:
-    crWeight=CAIRO_FONT_WEIGHT_BOLD;
-    break;
-  }
-  cairo_select_font_face(xg->cr, AQDG_Draw_Font_GetFontName(font), crSlant, crWeight);
-  cairo_set_font_size(xg->cr, AQDG_Draw_Font_GetFontSize(font));
+  _setFont(xg->cr, font);
 
   cairo_text_extents(xg->cr, text, &extents);
 
@@ -720,17 +528,9 @@ int _finish(AQDG_DRAW_CONTEXT *g)
 {
   AQDG_DRAW_CONTEXT_CAIRO *xg;
 
-  assert(g);
-  xg=GWEN_INHERIT_GETDATA(AQDG_DRAW_CONTEXT, AQDG_DRAW_CONTEXT_CAIRO, g);
-  assert(xg);
-
-  if (xg->surface==NULL) {
-    DBG_ERROR(0, "No surface created");
-    return GWEN_ERROR_INVALID;
-  }
-
-  if (xg->cr==NULL) {
-    DBG_INFO(0, "Graphics context not active, call \"AQDG_Draw_Context_BeginDraw()\" before");
+  xg=_ensureFullCairoContext(g);
+  if (xg==NULL) {
+    DBG_INFO(NULL, "here");
     return GWEN_ERROR_INVALID;
   }
 
@@ -764,6 +564,115 @@ int _finish(AQDG_DRAW_CONTEXT *g)
 
 
 
+AQDG_DRAW_CONTEXT_CAIRO *_ensureFullCairoContext(const AQDG_DRAW_CONTEXT *g)
+{
+  if (g) {
+    AQDG_DRAW_CONTEXT_CAIRO *xg;
+
+    xg=_ensureCairoSurface(g);
+    if (xg) {
+      if (xg->cr==NULL) {
+        DBG_INFO(0, "Graphics context not active, call \"AQDG_Draw_Context_BeginDraw()\" first");
+        return NULL;
+      }
+      return xg;
+    }
+  }
+  return NULL;
+}
+
+
+
+AQDG_DRAW_CONTEXT_CAIRO *_ensureCairoSurface(const AQDG_DRAW_CONTEXT *g)
+{
+  if (g) {
+    AQDG_DRAW_CONTEXT_CAIRO *xg;
+
+    xg=GWEN_INHERIT_GETDATA(AQDG_DRAW_CONTEXT, AQDG_DRAW_CONTEXT_CAIRO, g);
+    if (xg) {
+      if (xg->surface==NULL) {
+        DBG_ERROR(0, "No surface created");
+        return NULL;
+      }
+    }
+    return xg;
+  }
+  return NULL;
+}
+
+
+
+void _setColourAndWidthFromPen(cairo_t *cr, const AQDG_DRAW_PEN *pen)
+{
+  uint32_t fgCol;
+  double red, green, blue;
+
+  /*  set foreground color */;
+  fgCol=AQDG_Draw_Pen_GetFrontColour(pen);
+  red=(double)((fgCol>>24) & 0xff)/255.0;
+  green=(double)((fgCol>>16) & 0xff)/255.0;
+  blue=(double)((fgCol>>8) & 0xff)/255.0;
+  cairo_set_source_rgb(cr, red, green, blue);
+
+  /* set line width */
+  cairo_set_line_width(cr, AQDG_Draw_Pen_GetLineWidth(pen));
+}
+
+
+
+void _setDashType(cairo_t *cr, int dashType)
+{
+  switch (dashType) {
+  default:
+  case 0:
+    cairo_set_dash(cr, NULL, 0, 0.0);
+    break;
+  case 1:
+    cairo_set_dash(cr, AQDG_Draw_ContextCairo_DashPattern1, 2, 0.0);
+    break;
+  case 2:
+    cairo_set_dash(cr, AQDG_Draw_ContextCairo_DashPattern2, 2, 0.0);
+    break;
+  case 3:
+    cairo_set_dash(cr, AQDG_Draw_ContextCairo_DashPattern3, 2, 0.0);
+    break;
+  case 4:
+    cairo_set_dash(cr, AQDG_Draw_ContextCairo_DashPattern4, 2, 0.0);
+    break;
+  case 5:
+    cairo_set_dash(cr, AQDG_Draw_ContextCairo_DashPattern5, 2, 0.0);
+    break;
+  }
+}
+
+
+void _setFont(cairo_t *cr, AQDG_DRAW_FONT *font)
+{
+  int crSlant;
+  int crWeight;
+
+  switch (AQDG_Draw_Font_GetFontSlant(font)) {
+  default:
+  case AQDG_Slant_None:
+    crSlant=CAIRO_FONT_SLANT_NORMAL;
+    break;
+  case AQDG_Slant_Italic:
+    crSlant=CAIRO_FONT_SLANT_ITALIC;
+    break;
+  }
+
+  switch (AQDG_Draw_Font_GetFontWeight(font)) {
+  default:
+  case AQDG_Weight_None:
+    crWeight=CAIRO_FONT_WEIGHT_NORMAL;
+    break;
+  case AQDG_Weight_Bold:
+    crWeight=CAIRO_FONT_WEIGHT_BOLD;
+    break;
+  }
+  cairo_select_font_face(cr, AQDG_Draw_Font_GetFontName(font), crSlant, crWeight);
+  cairo_set_font_size(cr, AQDG_Draw_Font_GetFontSize(font));
+}