[recipes] Break out unit parser as a separate file

[Matthias Clasen <matthiasc src gnome org>]

commit 98599a8102988290d1913488cd2a5d9d18694bac
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Dec 24 09:41:21 2016 -0500

    Break out unit parser as a separate file
    
    This will make it easy to write tests, and also helps
    with adding new functionality later.
    While we are at it, add some more units to the list.

 src/Makefile.am |    2 +
 src/gr-unit.c   |  152 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/gr-unit.h   |   33 ++++++++++++
 3 files changed, 187 insertions(+), 0 deletions(-)
---
diff --git a/src/Makefile.am b/src/Makefile.am
index 0c39143..3d8c4da 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -95,6 +95,8 @@ recipes_SOURCES = \
        gr-timer-widget.c       \
        gr-toggle-button.h      \
        gr-toggle-button.c      \
+       gr-unit.h               \
+       gr-unit.c               \
        gr-utils.h              \
        gr-utils.c              \
        gr-window.h             \
diff --git a/src/gr-unit.c b/src/gr-unit.c
new file mode 100644
index 0000000..be4d0b0
--- /dev/null
+++ b/src/gr-unit.c
@@ -0,0 +1,152 @@
+/* gr-unit.c
+ *
+ * Copyright (C) 2016 Matthias Clasen <mclasen redhat com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include <glib/gi18n.h>
+#include <gio/gio.h>
+
+#include "gr-unit.h"
+
+static const char * const names[] = {
+        "gram",
+        "kilogram",
+        "liter",
+        "deciliter",
+        "milliliter",
+        "pound",
+        "box",
+        "tablespoon",
+        "teaspoon",
+        "cup",
+        NULL
+};
+
+typedef struct {
+        const char *unit;
+        const char *abbreviation;
+        const char *display_name;
+        const char *plural;
+} GrUnit;
+
+static GrUnit units[] = {
+        { "g",  NC_("unit", "g"), NC_("unit", "gram"), NC_("unit", "grams") },
+        { "kg", NC_("unit", "kg"), NC_("unit", "kilogram"), NC_("unit", "kilograms") },
+        { "lb", NC_("unit", "lb"), NC_("unit", "pound"), NC_("unit", "pounds") },
+        { "oz", NC_("unit", "oz"), NC_("unit", "ounce"), NC_("unit", "ounces") },
+        { "l",  NC_("unit", "l"), NC_("unit", "liter"), NC_("unit", "liters") },
+        { "dl", NC_("unit", "dl"), NC_("unit", "deciliter"), NC_("unit", "deciliters") },
+        { "ml", NC_("unit", "ml"), NC_("unit", "milliliter"), NC_("unit", "milliliters") },
+        { "fl oz", NC_("unit", "fl oz"), NC_("unit", "fluid ounce"), NC_("unit", "fluid ounces") },
+        { "pt", NC_("unit", "pt"), NC_("unit", "pint"), NC_("unit", "pints") },
+        { "qt", NC_("unit", "qt"), NC_("unit", "quart"), NC_("unit", "quarts") },
+        { "gal", NC_("unit", "gal"), NC_("unit", "gallon"), NC_("unit", "gallons") },
+        { "cup", NC_("unit", "cup"), NC_("unit", "cup"), NC_("unit", "cups") },
+        { "tbsp", NC_("unit", "tbsp"), NC_("unit", "tablespoon"), NC_("unit", "tablespoons") },
+        { "tsp", NC_("unit", "tsp"), NC_("unit", "teaspoon"), NC_("unit", "teaspoons") },
+        { "box", NC_("unit", "box"), NC_("unit", "box"), NC_("unit", "boxes") },
+        { "package", NC_("unit", "pkg"), NC_("unit", "package"), NC_("unit", "packages") },
+};
+
+const char **
+gr_unit_get_names (void)
+{
+        return (const char **)names;
+}
+
+static GrUnit *
+find_unit (const char *name)
+{
+        int i;
+        for (i = 0; i < G_N_ELEMENTS (units); i++) {
+                if (strcmp (units[i].unit, name) == 0)
+                        return &(units[i]);
+        }
+        return NULL;
+}
+
+const char *
+gr_unit_get_display_name (const char *name)
+{
+        GrUnit *unit = find_unit (name);
+        if (unit)
+                return g_dpgettext2 (NULL, "unit", unit->display_name);
+        return NULL;
+}
+
+const char *
+gr_unit_get_plural (const char *name)
+{
+        GrUnit *unit = find_unit (name);
+        if (unit)
+                return g_dpgettext2 (NULL, "unit", unit->plural);
+        return NULL;
+}
+
+const char *
+gr_unit_get_abbreviation (const char *name)
+{
+        GrUnit *unit = find_unit (name);
+        if (unit)
+                return g_dpgettext2 (NULL, "unit", unit->abbreviation);
+        return NULL;
+}
+
+static gboolean
+space_or_nul (char p)
+{
+        return (p == '\0' || g_ascii_isspace (p));
+}
+
+const char *
+gr_unit_parse (char   **input,
+               GError **error)
+{
+        int i;
+        const char *nu;
+
+        for (i = 0; i < G_N_ELEMENTS (units); i++) {
+                nu = g_dpgettext2 (NULL, "unit", units[i].plural);
+                if (g_str_has_prefix (*input, nu) && space_or_nul ((*input)[strlen (nu)])) {
+                        *input += strlen (nu);
+                        return units[i].unit;
+                }
+        }
+
+        for (i = 0; i < G_N_ELEMENTS (units); i++) {
+                nu = g_dpgettext2 (NULL, "unit", units[i].display_name);
+                if (g_str_has_prefix (*input, nu) && space_or_nul ((*input)[strlen (nu)])) {
+                        *input += strlen (nu);
+                        return units[i].unit;
+                }
+        }
+
+        for (i = 0; i < G_N_ELEMENTS (units); i++) {
+                nu = g_dpgettext2 (NULL, "unit", units[i].abbreviation);
+                if (g_str_has_prefix (*input, nu) && space_or_nul ((*input)[strlen (nu)])) {
+                        *input += strlen (nu);
+                        return units[i].unit;
+                }
+        }
+
+        g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
+                     _("I don’t know this unit: %s"), *input);
+
+        return NULL;
+}
+
diff --git a/src/gr-unit.h b/src/gr-unit.h
new file mode 100644
index 0000000..9698367
--- /dev/null
+++ b/src/gr-unit.h
@@ -0,0 +1,33 @@
+/* gr-unit.h
+ *
+ * Copyright (C) 2016 Matthias Clasen <mclasen redhat com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <glib.h>
+
+G_BEGIN_DECLS
+
+const char *gr_unit_parse (char   **string,
+                           GError **error);
+
+const char **gr_unit_get_names (void);
+const char  *gr_unit_get_abbreviation (const char *name);
+const char  *gr_unit_get_display_name (const char *name);
+const char  *gr_unit_get_plural       (const char *name);
+
+G_END_DECLS