altoslib: Switch distance from m/ft to km/miles for large values

This adds lots of infrastructure to deal with making the unit used
depend on the value itself, and then uses it only for distances.

Signed-off-by: Keith Packard <keithp@keithp.com>

5 files changed, 239 insertions, 44 deletions

diff --git a/altoslib/AltosDistance.java b/altoslib/AltosDistance.java
index b68a4525..1ec39f8d 100644
--- a/altoslib/AltosDistance.java
+++ b/altoslib/AltosDistance.java
@@ -54,4 +54,58 @@ public class AltosDistance extends AltosUnits {
 			return 1;
 		return 0;
 	}
-}
\ No newline at end of file
+
+	public AltosDistance() {
+		range_metric = new AltosUnitsRange[2];
+
+		range_metric[0] = new AltosUnitsRange(0, "m", "meters") {
+				double value(double v) {
+					return v;
+				}
+				int show_fraction(int width) {
+					return width / 9;
+				}
+				int say_fraction() {
+					return 0;
+				}
+			};
+		range_metric[1] = new AltosUnitsRange(2000, "km", "kilometers") {
+				double value(double v) {
+					return v / 1000;
+				}
+				int show_fraction(int width) {
+					return width / 5;
+				}
+				int say_fraction() {
+					return 1;
+				}
+			};
+
+		range_imperial = new AltosUnitsRange[2];
+
+		range_imperial[0] = new AltosUnitsRange(0, "ft", "feet") {
+				double value(double v) {
+					return AltosConvert.meters_to_feet(v);
+				}
+				int show_fraction(int width) {
+					return width / 9;
+				}
+				int say_fraction() {
+					return 0;
+				}
+			};
+
+		range_imperial[1] = new AltosUnitsRange(AltosConvert.feet_to_meters(5280),
+							"mi", "miles") {
+				double value(double v) {
+					return AltosConvert.meters_to_miles(v);
+				}
+				int show_fraction(int width) {
+					return width / 5;
+				}
+				int say_fraction() {
+					return 1;
+				}
+			};
+	}
+}
diff --git a/altoslib/AltosPyro.java b/altoslib/AltosPyro.java
index 28e65bc2..3afd03e0 100644
--- a/altoslib/AltosPyro.java
+++ b/altoslib/AltosPyro.java
@@ -138,7 +138,7 @@ public class AltosPyro {
 			units = pyro_to_units.get(flag);
 		if (units == null)
 			return name;
-		return String.format ("%s (%s)", name, units.show_units());
+		return String.format ("%s (%s)", name, units.parse_units());
 	}
 
 	public static AltosUnits pyro_to_units(int flag) {
diff --git a/altoslib/AltosUnits.java b/altoslib/AltosUnits.java
index 13b9dbe6..bc53d4a0 100644
--- a/altoslib/AltosUnits.java
+++ b/altoslib/AltosUnits.java
@@ -21,6 +21,21 @@ import java.text.*;
 
 public abstract class AltosUnits {
 
+	AltosUnitsRange[]	range_metric, range_imperial;
+
+	private AltosUnitsRange range(double v, boolean imperial_units) {
+		AltosUnitsRange[]	ranges = imperial_units ? range_imperial : range_metric;
+
+		for (int i = ranges.length - 1; i > 0; i--)
+			if (v >= ranges[i].lower_limit)
+				return ranges[i];
+		return ranges[0];
+	}
+
+	private AltosUnitsRange first_range(boolean imperial_units) {
+		return imperial_units ? range_imperial[0] : range_metric[0];
+	}
+
 	public abstract double value(double v, boolean imperial_units);
 
 	public abstract double inverse(double v, boolean imperial_units);
@@ -31,89 +46,168 @@ public abstract class AltosUnits {
 
 	public abstract int show_fraction(int width, boolean imperial_units);
 
-	public double parse_locale(String s, boolean imperial_units) throws ParseException {
-		double v = AltosParse.parse_double_locale(s);
-		return inverse(v, imperial_units);
+	private double value(double v) {
+		return value(v, AltosConvert.imperial_units);
 	}
 
-	public double parse_net(String s, boolean imperial_units) throws ParseException {
-		double v = AltosParse.parse_double_net(s);
-		return inverse(v, imperial_units);
+	private double inverse(double v) {
+		return inverse(v, AltosConvert.imperial_units);
 	}
 
-	public double parse_locale(String s) throws ParseException {
-		return parse_locale(s, AltosConvert.imperial_units);
+	private String show_units() {
+		return show_units(AltosConvert.imperial_units);
 	}
 
-	public double parse_net(String s) throws ParseException {
-		return parse_net(s, AltosConvert.imperial_units);
+	private String say_units() {
+		return say_units(AltosConvert.imperial_units);
 	}
 
-	public double value(double v) {
-		return value(v, AltosConvert.imperial_units);
+	private int show_fraction(int width) {
+		return show_fraction(width, AltosConvert.imperial_units);
 	}
 
-	public double inverse(double v) {
-		return inverse(v, AltosConvert.imperial_units);
+	private int say_fraction(boolean imperial_units) {
+		return 0;
 	}
 
-	public String show_units() {
-		return show_units(AltosConvert.imperial_units);
+	private String show_format(AltosUnitsRange range, int width) {
+		return String.format("%%%d.%df %s", width, range.show_fraction(width), range.show_units);
 	}
 
-	public String say_units() {
-		return say_units(AltosConvert.imperial_units);
+	private String say_format(AltosUnitsRange range) {
+		return String.format("%%1.%df", range.say_fraction());
 	}
 
-	public int show_fraction(int width) {
-		return show_fraction(width, AltosConvert.imperial_units);
+	private String say_units_format(AltosUnitsRange range)  {
+		return String.format("%%1.%df %s", range.say_fraction(), range.say_units);
 	}
 
-	int say_fraction(boolean imperial_units) {
-		return 0;
+	public String show(int width, double v, boolean imperial_units) {
+		AltosUnitsRange range = range(v, imperial_units);
+
+		return String.format(show_format(range, width), range.value(v));
+	}
+
+	public String say(double v, boolean imperial_units) {
+		AltosUnitsRange range = range(v, imperial_units);
+
+		return String.format(say_format(range), range.value(v));
+	}
+
+	public String say_units(double v, boolean imperial_units) {
+		AltosUnitsRange range = range(v, imperial_units);
+
+		return String.format(say_units_format(range), range.value(v));
+	}
+
+	public String show(int width, double v) {
+		return show(width, v, AltosConvert.imperial_units);
+	}
+
+	public String say(double v) {
+		return say(v, AltosConvert.imperial_units);
+	}
+
+	public String say_units(double v) {
+		return say_units(v, AltosConvert.imperial_units);
+	}
+
+	/* Parsing functions. Use the first range of the type */
+	public String parse_units(boolean imperial_units) {
+		return first_range(imperial_units).show_units;
+	}
+
+	public String parse_units() {
+		return parse_units(AltosConvert.imperial_units);
+	}
+
+	public double parse_value(double v, boolean imperial_units) {
+		return first_range(imperial_units).value(v);
+	}
+
+	public double parse_value(double v) {
+		return parse_value(v, AltosConvert.imperial_units);
 	}
 
-	private String show_format(int width, boolean imperial_units) {
-		return String.format("%%%d.%df %s", width, show_fraction(width, imperial_units), show_units(imperial_units));
+	/* Graphing functions. Use the first range of the type */
+	public String graph_units(boolean imperial_units) {
+		return first_range(imperial_units).show_units;
 	}
 
-	private String say_format(boolean imperial_units) {
-		return String.format("%%1.%df", say_fraction(imperial_units));
+	public String graph_units() {
+		return graph_units(AltosConvert.imperial_units);
 	}
 
-	private String say_units_format(boolean imperial_units) {
-		return String.format("%%1.%df %s", say_fraction(imperial_units), say_units(imperial_units));
+	public double graph_value(double v, boolean imperial_units) {
+		return first_range(imperial_units).value(v);
+	}
+
+	public double graph_value(double v) {
+		return graph_value(v, AltosConvert.imperial_units);
+	}
+
+	private String graph_format(AltosUnitsRange range, int width) {
+		return String.format(String.format("%%%d.%df", width, range.show_fraction(width)), 0.0);
 	}
 
 	public String graph_format(int width, boolean imperial_units) {
-		return String.format(String.format("%%%d.%df", width, show_fraction(width, imperial_units)), 0.0);
+		return graph_format(first_range(imperial_units), width);
 	}
 
 	public String graph_format(int width) {
 		return graph_format(width, AltosConvert.imperial_units);
 	}
 
-	public String show(int width, double v, boolean imperial_units) {
-		return String.format(show_format(width, imperial_units), value(v, imperial_units));
+	/* Parsing functions. */
+	public double parse_locale(String s, boolean imperial_units) throws ParseException {
+		double v = AltosParse.parse_double_locale(s);
+		return inverse(v, imperial_units);
 	}
 
-	public String show(int width, double v) {
-		return show(width, v, AltosConvert.imperial_units);
+	public double parse_net(String s, boolean imperial_units) throws ParseException {
+		double v = AltosParse.parse_double_net(s);
+		return inverse(v, imperial_units);
 	}
 
-	public String say(double v, boolean imperial_units) {
-		return String.format(say_format(imperial_units), value(v, imperial_units));
+	public double parse_locale(String s) throws ParseException {
+		return parse_locale(s, AltosConvert.imperial_units);
 	}
 
-	public String say(double v) {
-		return say(v, AltosConvert.imperial_units);
+	public double parse_net(String s) throws ParseException {
+		return parse_net(s, AltosConvert.imperial_units);
 	}
 
-	public String say_units(double v, boolean imperial_units) {
-		return String.format(say_units_format(imperial_units), value(v, imperial_units));
-	}
+	public AltosUnits() {
+		range_metric = new AltosUnitsRange[1];
 
-	public String say_units(double v) {
-		return say_units(v, AltosConvert.imperial_units);
+		range_metric[0] = new AltosUnitsRange(this, false) {
+				double value(double v) {
+					return units.value(v, false);
+				}
+
+				int show_fraction(int width) {
+					return units.show_fraction(width, false);
+				}
+
+				int say_fraction() {
+					return units.say_fraction(false);
+				}
+			};
+
+		range_imperial = new AltosUnitsRange[1];
+
+		range_imperial[0] = new AltosUnitsRange(this, true) {
+				double value(double v) {
+					return units.value(v, true);
+				}
+
+				int show_fraction(int width) {
+					return units.show_fraction(width, true);
+				}
+
+				int say_fraction() {
+					return units.say_fraction(true);
+				}
+			};
 	}
 }
diff --git a/altoslib/AltosUnitsRange.java b/altoslib/AltosUnitsRange.java
new file mode 100644
index 00000000..9239481a
--- /dev/null
+++ b/altoslib/AltosUnitsRange.java
@@ -0,0 +1,46 @@
+/*
+ * Copyright © 2016 Keith Packard <keithp@keithp.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; version 2 of the License.
+ *
+ * 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, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+package org.altusmetrum.altoslib_10;
+
+import java.text.*;
+
+public abstract class AltosUnitsRange {
+
+	AltosUnits	units;
+
+	double		lower_limit;
+	String		show_units;
+	String		say_units;
+
+	abstract double	value(double v);
+	abstract int show_fraction(int width);
+	abstract int say_fraction();
+
+	AltosUnitsRange(AltosUnits units, boolean imperial_units) {
+		this.units = units;
+		this.show_units = units.show_units(imperial_units);
+		this.say_units = units.say_units(imperial_units);
+	}
+
+	AltosUnitsRange(double lower_limit, String show_units, String say_units) {
+		this.units = null;
+		this.lower_limit = lower_limit;
+		this.show_units = show_units;
+		this.say_units = say_units;
+	}
+}
diff --git a/altoslib/Makefile.am b/altoslib/Makefile.am
index dc9da8fd..f3219839 100644
--- a/altoslib/Makefile.am
+++ b/altoslib/Makefile.am
@@ -118,6 +118,7 @@ altoslib_JAVA = \
 	AltosIMU.java \
 	AltosMag.java \
 	AltosUnits.java \
+	AltosUnitsRange.java \
 	AltosDistance.java \
 	AltosHeight.java \
 	AltosSpeed.java \