[gnumeric] xlsx: fix placement of axes in file.

[Morten Welinder <mortenw src gnome org>]

commit 8a25bf3aa4b0b047f9e5777e96cbefec50320b73
Author: Morten Welinder <terra gnome org>
Date:   Sun Mar 8 15:00:46 2015 -0400

    xlsx: fix placement of axes in file.
    
    All plots, then all axes.  Not interleaved.

 plugins/excel/ChangeLog            |    7 ++++++
 plugins/excel/xlsx-write-drawing.c |   38 ++++++++++++++++++++++++-----------
 2 files changed, 33 insertions(+), 12 deletions(-)
---
diff --git a/plugins/excel/ChangeLog b/plugins/excel/ChangeLog
index a15c3c0..7356636 100644
--- a/plugins/excel/ChangeLog
+++ b/plugins/excel/ChangeLog
@@ -1,3 +1,10 @@
+2015-03-08  Morten Welinder  <terra gnome org>
+
+       * xlsx-write-drawing.c (xlsx_write_one_plot): Don't write axes
+       here; return a list of needed axes instead.
+       (xlsx_write_plots): Write the union of needed axes after all the
+       plots.
+
 2015-03-07  Morten Welinder  <terra gnome org>
 
        * xlsx-write-drawing.c (xlsx_write_plots): Write all plots, not
diff --git a/plugins/excel/xlsx-write-drawing.c b/plugins/excel/xlsx-write-drawing.c
index 4be1f41..0b81b14 100644
--- a/plugins/excel/xlsx-write-drawing.c
+++ b/plugins/excel/xlsx-write-drawing.c
@@ -773,7 +773,7 @@ xlsx_write_axis (XLSXWriteState *state, GsfXMLOut *xml, GogPlot *plot, GogAxis *
 }
 
 
-static void
+static GSList *
 xlsx_write_one_plot (XLSXWriteState *state, GsfXMLOut *xml, GogObject const *chart, GogPlot *plot)
 {
        double explosion = 0.;
@@ -789,6 +789,7 @@ xlsx_write_one_plot (XLSXWriteState *state, GsfXMLOut *xml, GogObject const *cha
        gboolean use_xy = FALSE;
        gboolean set_smooth = FALSE;
        gboolean set_invert = FALSE;
+       GSList *axes = NULL;
 
        g_object_get (G_OBJECT (plot),
                      "vary-style-by-element", &vary_by_element,
@@ -800,7 +801,7 @@ xlsx_write_one_plot (XLSXWriteState *state, GsfXMLOut *xml, GogObject const *cha
        default:
        case XLSX_PT_UNKNOWN:
                g_warning ("unexpected plot type %s", plot_type_name);
-               return;
+               return NULL;
 
        case XLSX_PT_GOGAREAPLOT:
                gsf_xml_out_start_element (xml, "c:areaChart");
@@ -1083,20 +1084,13 @@ xlsx_write_one_plot (XLSXWriteState *state, GsfXMLOut *xml, GogObject const *cha
                if (axis_type[i] != GOG_AXIS_UNKNOWN) {
                        GogAxis *axis = gog_plot_get_axis (GOG_PLOT (plot), axis_type[i]);
                        xlsx_write_chart_uint (xml, "c:axId", xlsx_get_axid (state, axis));
+                       axes = g_slist_append (axes, axis);
                }
        }
 
        gsf_xml_out_end_element (xml);
 
-       /* Write axes */
-       /* first category axis */
-       /* FIXME: might be a date axis? */
-       for (i = 0; i < 3; i++) {
-               if (axis_type[i] != GOG_AXIS_UNKNOWN) {
-                       GogAxis *axis = gog_plot_get_axis (GOG_PLOT (plot), axis_type[i]);
-                       xlsx_write_axis (state, xml, GOG_PLOT (plot), axis);
-               }
-       }
+       return axes;
 }
 
 static void
@@ -1104,13 +1098,33 @@ xlsx_write_plots (XLSXWriteState *state, GsfXMLOut *xml, GogObject const *chart)
 {
        GSList *plots, *l;
        GogObjectRole const *role = gog_object_find_role_by_name (GOG_OBJECT (chart), "Plot");
+       GHashTable *axis_to_plot = g_hash_table_new (NULL, NULL);
+       GSList *axes = NULL;
 
        plots = gog_object_get_children (GOG_OBJECT (chart), role);
        for (l = plots; l; l = l->next) {
                GogPlot *plot = l->data;
-               xlsx_write_one_plot (state, xml, chart, plot);
+               GSList *plot_axes, *al;
+
+               plot_axes = xlsx_write_one_plot (state, xml, chart, plot);
+               for (al = plot_axes; al; al = al->next) {
+                       GogAxis *axis = al->data;
+                       if (!g_hash_table_lookup (axis_to_plot, axis)) {
+                               g_hash_table_insert (axis_to_plot, axis, plot);
+                               axes = g_slist_append (axes, axis);
+                       }
+               }
+               g_slist_free (plot_axes);
        }
        g_slist_free (plots);
+
+       for (l = axes; l; l = l->next) {
+               GogAxis *axis = l->data;
+               GogPlot *plot = g_hash_table_lookup (axis_to_plot, axis);
+               xlsx_write_axis (state, xml, plot, axis);
+       }
+       g_slist_free (axes);
+       g_hash_table_destroy (axis_to_plot);
 }
 
 static void