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/*
 * Copyright (C) 2024 Nicolas Schodet
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

/*
 * Convert floating point values to integer, check conversion is right.
 *
 * Actual check is done on the attached computer, see float.expect.
 *
 * When converting a float to an integer, if the integer is not able to
 * represent the value, the behavior is implementation defined.
 *
 * The original firmware source code depends on this implementation defined
 * behavior from the C compiler.
 *
 * The LEGO MINDSTORMS NXT Executable File Specification does not define what
 * is the expected behavior for the firmware because it was released for
 * version 1.03, before float was supported. However it says: "At the scalar
 * level, data type conversions behave identically to type casts in ANSI C.".
 *
 * For NXT Improved firmware, I decided to follow the behavior of the original
 * firmware binary, which is:
 *
 *  - Negative values to unsigned numbers: large positive integer (two's
 *  complement).
 *  - Round to nearest for SETOUT instruction, truncate for other operations.
 *
 * There are so many code paths inside the firmware to do the same thing that
 * I may have missed some other cases. If you find such cases, please update
 * this test.
 */

#include "term.h"

task main()
{
    float a[4] = {-12.9, -12.34, 12.34, 12.9};
    int i;

    Wait(1000);

    /*
     * Test conversion using MOV instruction.
     */
    for (i = 0; i < 4; i++) {
        float af = a[i];
        char ac = af;
        unsigned char auc = af;
        short as = af;
        unsigned short aus = af;
        long al = af;
        unsigned long aul = af;

        TermText("move   "); TermNumNl(af);
        TermText(" char  "); TermNum(ac); TermText(" "); TermNumNl(auc);
        TermText(" short "); TermNum(as); TermText(" "); TermNumNl(aus);
        TermText(" long  "); TermNum(al); TermText(" "); TermNumNl(aul);

        Wait(100);
    }

    /*
     * Test conversion using MOV instruction with an array.
     */
    while (1) {
        char ac[4];
        ac = a;
        unsigned char auc[4];
        auc = a;
        short as[4];
        as = a;
        unsigned short aus[4];
        aus = a;
        long al[4];
        al = a;
        unsigned long aul[4];
        aul = a;
        for (i = 0; i < 4; i++) {
            TermText("move[] "); TermNumNl(a[i]);
            TermText(" char  "); TermNum(ac[i]); TermText(" "); TermNumNl(auc[i]);
            TermText(" short "); TermNum(as[i]); TermText(" "); TermNumNl(aus[i]);
            TermText(" long  "); TermNum(al[i]); TermText(" "); TermNumNl(aul[i]);

            Wait(100);
        }
        break;
    }

    /*
     * Test conversion using NEG instruction.
     */
    for (i = 0; i < 4; i++) {
        float af = a[i];
        char ac = -af;
        unsigned char auc = -af;
        short as = -af;
        unsigned short aus = -af;
        long al = -af;
        unsigned long aul = -af;

        TermText("neg    "); TermNumNl(af);
        TermText(" char  "); TermNum(ac); TermText(" "); TermNumNl(auc);
        TermText(" short "); TermNum(as); TermText(" "); TermNumNl(aus);
        TermText(" long  "); TermNum(al); TermText(" "); TermNumNl(aul);

        Wait(100);
    }

    /*
     * Test conversion using SETOUT/GETOUT instructions.
     */
    for (i = 0; i < 4; i++) {
        float af = a[i];
        SetOutput(OUT_A, PowerField, af, RegPValueField, af);
        char ac = GetOutput(OUT_A, PowerField);
        unsigned char auc = GetOutput(OUT_A, RegPValueField);

        TermText("out    "); TermNumNl(af);
        TermText(" char  "); TermNum(ac); TermText(" "); TermNumNl(auc);

        Wait(100);
    }
}