// $Id$
// From Philippe Le Hegaret (Philippe.Le_Hegaret@sophia.inria.fr)
//
// (c) COPYRIGHT MIT, ERCIM and Keio University, 2011
// Please first read the full copyright statement in file COPYRIGHT.html
package org.w3c.css.values;

import org.w3c.css.properties.css.CssProperty;
import org.w3c.css.util.ApplContext;
import org.w3c.css.util.CssVersion;
import org.w3c.css.util.InvalidParamException;

import java.math.BigDecimal;

/**
 * A CSS number.
 *
 * @version $Revision$
 */
public class CssNumber extends CssCheckableValue implements CssValueFloat {

    public static final int type = CssTypes.CSS_NUMBER;

    public final int getType() {
        return type;
    }

    ApplContext ac;
    BigDecimal value;
    boolean isInt = false;
    String _strval = null;

    /**
     * Create a new CssNumber
     */
    public CssNumber() {
    }

    /**
     * Create a new CssNumber
     */
    public CssNumber(ApplContext ac, float value) {
        this.ac = ac;
        this.value = new BigDecimal(value);
    }

    public CssNumber(float value) {
        this.value = new BigDecimal(value);
    }

    /**
     * Set the value of this frequency.
     *
     * @param s  the string representation of the frequency.
     * @param ac For errors and warnings reports.
     */
    public void set(String s, ApplContext ac)
            throws InvalidParamException {
        boolean negate = false;
        String val;
        if (ac.getCssVersion().compareTo(CssVersion.CSS3) < 0) {
            // check for scientific notation in CSS < 3
            if (s.indexOf('e') >= 0 || s.indexOf('E') >= 0) {
                throw new InvalidParamException("value", "number", s, ac);
            }
        }
        if (s.startsWith("-")) {
            negate = true;
            val = s.substring(1);
        } else if (s.startsWith("+")) {
            val = s.substring(1);
        } else {
            val = s;
        }

        if (val.equalsIgnoreCase("pi")) {
            value = BigDecimal.valueOf(Math.PI);
            isInt = false;
            _strval = "pi";
        } else if (val.equalsIgnoreCase("e")) {
            value = BigDecimal.valueOf(Math.E);
            isInt = false;
            _strval = "e";
        } else {
            value = new BigDecimal(val);
            isInt = (val.indexOf('.') < 0);
/*		CSS integers are not value-based integers.
        try {
			value.toBigIntegerExact();
			isInt = true;
		} catch (ArithmeticException e) {
			isInt = false;
		} */
        }
        if (negate) {
            value = value.negate();
            if (_strval != null) {
                _strval = '-' + _strval;
            }
        }
        this.ac = ac;
    }

    /**
     * set the native value
     */
    public void setValue(BigDecimal v) {
        value = v;
        try {
            v.toBigIntegerExact();
            isInt = true;
        } catch (ArithmeticException e) {
            isInt = false;
        }
    }

    /**
     * Set the value explicitly
     */
    public void setIntValue(int v) {
        isInt = true;
        value = new BigDecimal(v);

    }

    /**
     * Set the value explicitly
     */
    public void setFloatValue(float v) {
        isInt = false;
        value = new BigDecimal(v);
    }

    /**
     * Returns the value
     */
    public Object get() {
        return value;
    }

    /**
     * Return the float value
     */
    public float getValue() {
        return value.floatValue();
    }

    public BigDecimal getBigDecimalValue() {
        return value;
    }

    public int getInt() throws InvalidParamException {
        if (isInt) {
            try {
                return value.intValueExact();
            } catch (ArithmeticException aex) {
                throw new InvalidParamException("out-of-range", ac);
            }
        }
        // FIXME ???
        throw new InvalidParamException("invalid-color", ac);
    }

    public boolean isInteger() {
        return isInt;
    }

    /**
     * Returns true is the value is positive of null
     *
     * @return a boolean
     */
    public boolean isPositive() {
        return (value.signum() >= 0);
    }

    /**
     * Returns true is the value is positive of null
     *
     * @return a boolean
     */
    public boolean isStrictlyPositive() {
        return (value.signum() == 1);
    }

    /**
     * Returns true is the value is zero
     *
     * @return a boolean
     */
    public boolean isZero() {
        return (BigDecimal.ZERO.compareTo(value) == 0);
    }

    /**
     * Returns a length.
     * Only zero can be a length.
     *
     * @throws InvalidParamException The value is not zero
     */
    public CssLength getLength() throws InvalidParamException {
        if (value.compareTo(BigDecimal.ZERO) == 0) {
            return new CssLength();
        }
        throw new InvalidParamException("zero", "length", ac);
    }

    /**
     * Returns a percentage.
     * Only zero can be a percentage.
     *
     * @throws InvalidParamException The value is not zero
     */
    public CssPercentage getPercentage() throws InvalidParamException {
        if (value.compareTo(BigDecimal.ZERO) == 0) {
            return new CssPercentage();
        }
        throw new InvalidParamException("zero",
                value.toString(),
                "percentage", ac);
    }

    /**
     * Returns a time.
     * Only zero can be a time.
     *
     * @throws InvalidParamException The value is not zero
     */
    public CssTime getTime() throws InvalidParamException {
        if (value.compareTo(BigDecimal.ZERO) == 0) {
            return new CssTime();
        }
        throw new InvalidParamException("zero", value.toString(),
                "time", ac);
    }

    /**
     * Returns an angle.
     * Only zero can be an angle.
     *
     * @throws InvalidParamException The value is not zero
     */
    public CssAngle getAngle() throws InvalidParamException {
        if (value.compareTo(BigDecimal.ZERO) == 0) {
            return new CssAngle();
        }
        throw new InvalidParamException("zero", value.toString(),
                "angle", ac);
    }

    /**
     * Returns a frequency.
     * Only zero can be a frequency.
     *
     * @throws InvalidParamException The value is not zero
     */
    public CssFrequency getFrequency() throws InvalidParamException {
        if (value.compareTo(BigDecimal.ZERO) == 0) {
            return new CssFrequency();
        }
        throw new InvalidParamException("zero",
                value.toString(), "frequency", ac);
    }

    public CssNumber getNumber() throws InvalidParamException {
        return this;
    }

    /**
     * Returns a string representation of the object.
     */
    public String toString() {
        if (_strval != null) {
            return _strval;
        }
        return value.toPlainString();
    }

    /**
     * Compares two values for equality.
     *
     * @param value The other value.
     */
    public boolean equals(Object value) {
        return (value instanceof CssNumber &&
                this.value.equals(((CssNumber) value).value));
    }

    /**
     * check if the value is lower or equal than...
     *
     * @param ac       the validation context
     * @param property the property the value is defined in
     * @throws InvalidParamException
     */
    public void checkLowerEqualThan(ApplContext ac, double d, CssProperty property)
            throws InvalidParamException {
        BigDecimal other = BigDecimal.valueOf(d);
        if (value.compareTo(other) > 0) {
            throw new InvalidParamException("lowerequal",
                    toString(), other.toPlainString(), ac);
        }
    }

    /**
     * check if the value is lower or equal than...
     *
     * @param ac       the validation context
     * @param property the property the value is defined in
     * @throws InvalidParamException
     */
    public void warnLowerEqualThan(ApplContext ac, double d, CssProperty property) {
        BigDecimal other = BigDecimal.valueOf(d);
        if (value.compareTo(other) > 0) {
            String[] s = new String[2];
            s[0] = toString();
            s[1] = other.toPlainString();
            ac.getFrame().addWarning("lowerequal", s);
        }
    }

    /**
     * check if the value is lower or equal than...
     *
     * @param ac       the validation context
     * @param property the property the value is defined in
     * @throws InvalidParamException
     */
    public void checkGreaterEqualThan(ApplContext ac, double d, CssProperty property)
            throws InvalidParamException {
        BigDecimal other = BigDecimal.valueOf(d);
        if (value.compareTo(other) < 0) {
            throw new InvalidParamException("greaterequal",
                    toString(), other.toPlainString(), ac);
        }
    }

    /**
     * check if the value is lower or equal than...
     *
     * @param ac       the validation context
     * @param property the property the value is defined in
     * @throws InvalidParamException
     */
    public void warnGreaterEqualThan(ApplContext ac, double d, CssProperty property) {
        BigDecimal other = BigDecimal.valueOf(d);
        if (value.compareTo(other) < 0) {
            String[] s = new String[2];
            s[0] = toString();
            s[1] = other.toPlainString();
            ac.getFrame().addWarning("greaterequal", s);
        }
    }


    /**
     * check if the value is equal to zero
     *
     * @param ac         the validation context
     * @param callername the String value of the object it is defined in
     * @throws InvalidParamException
     */
    public void checkEqualsZero(ApplContext ac, String callername)
            throws InvalidParamException {
        checkEqualsZero(ac, new String[]{"unit", toString(), callername});
    }

    /**
     * warn if the value is not zero
     *
     * @param ac         the validation context
     * @param callername the String value of the object it is defined in
     */
    public boolean warnEqualsZero(ApplContext ac, String callername) {
        return warnEqualsZero(ac, new String[]{"unit", callername});
    }

    /**
     * check if the value is an integer
     *
     * @param ac         the validation context
     * @param callername the property the value is defined in
     * @throws InvalidParamException
     */
    public void checkInteger(ApplContext ac, String callername)
            throws InvalidParamException {
        if (!isInteger()) {
            throw new InvalidParamException("integer",
                    new String[]{toString(), callername}, ac);
        }
    }
}