#include "global.h"

/**
 * Calculates the distances between `a` and `b`
 */
f32 OLib_Vec3fDist(Vec3f* a, Vec3f* b) {
    f32 dx = a->x - b->x;
    f32 dy = a->y - b->y;
    f32 dz = a->z - b->z;

    return sqrtf(SQ(dx) + SQ(dy) + SQ(dz));
}

/**
 * Calculates the distances between `a` and `b`, and outputs the vector
 * created by the difference into `dest`
 */

f32 OLib_Vec3fDistOutDiff(Vec3f* a, Vec3f* b, Vec3f* dest) {
    dest->x = a->x - b->x;
    dest->y = a->y - b->y;
    dest->z = a->z - b->z;

    return sqrtf(SQ(dest->x) + SQ(dest->y) + SQ(dest->z));
}

/**
 * Calculates the distances on the xz plane between `a` and `b`
 */
f32 OLib_Vec3fDistXZ(Vec3f* a, Vec3f* b) {
    return sqrtf(SQ(a->x - b->x) + SQ(a->z - b->z));
}

/**
 * Clamps `val` to a maximum of -`min` as `val` approaches zero, and a minimum of
 * `min` as `val` approaches zero
 */
f32 OLib_ClampMinDist(f32 val, f32 min) {
    return (min <= fabsf(val)) ? val : ((val >= 0) ? min : -min);
}

/**
 * Clamps `val` to a minimum of -`max` as `val` approaches -`max`, and a maximum of `max`
 * as `val` approaches `max`
 */
f32 OLib_ClampMaxDist(f32 val, f32 max) {
    return (fabsf(val) <= max) ? val : ((val >= 0) ? max : -max);
}

/**
 * Takes the difference of points b and a, and creates a normal vector
 */
Vec3f* OLib_Vec3fDistNormalize(Vec3f* dest, Vec3f* a, Vec3f* b) {
    Vec3f v1;
    Vec3f v2;
    f32 dist;

    v1.x = b->x - a->x;
    v1.y = b->y - a->y;
    v1.z = b->z - a->z;

    dist = OLib_ClampMinDist(sqrtf(SQ(v1.x) + SQ(v1.y) + SQ(v1.z)), 0.01f);

    v2.x = v1.x / dist;
    v2.y = v1.y / dist;
    v2.z = v1.z / dist;

    *dest = v2;

    return dest;
}

/**
 * Takes the spherical coordinate `sph`, and converts it into a x,y,z position
 */
Vec3f* OLib_VecSphToVec3f(Vec3f* dest, VecSph* sph) {
    Vec3f v;
    f32 sinPhi;
    f32 cosPhi;
    f32 sinTheta;
    f32 cosTheta;

    cosPhi = Math_Coss(sph->pitch);
    cosTheta = Math_Coss(sph->yaw);
    sinPhi = Math_Sins(sph->pitch);
    sinTheta = Math_Sins(sph->yaw);

    v.x = sph->r * sinPhi * sinTheta;
    v.y = sph->r * cosPhi;
    v.z = sph->r * sinPhi * cosTheta;

    *dest = v;

    return dest;
}

/**
 * Takes the geographic point `sph` and converts it into a x,y,z position
 */
Vec3f* OLib_VecSphGeoToVec3f(Vec3f* dest, VecSph* sph) {
    VecSph geo;

    geo.r = sph->r;
    geo.pitch = 0x3FFF - sph->pitch;
    geo.yaw = sph->yaw;

    return OLib_VecSphToVec3f(dest, &geo);
}

/**
 * Takes the point `vec`, and converts it into a spherical coordinate
 */
VecSph* OLib_Vec3fToVecSph(VecSph* dest, Vec3f* vec) {
    VecSph sph;

    f32 distSquared;
    f32 dist;

    distSquared = SQ(vec->x) + SQ(vec->z);
    dist = sqrtf(distSquared);

    if ((dist == 0.0f) && (vec->y == 0.0f)) {
        sph.pitch = 0;
    } else {
        sph.pitch = DEGF_TO_BINANG(RADF_TO_DEGF(Math_atan2f(dist, vec->y)));
    }

    sph.r = sqrtf(SQ(vec->y) + distSquared);
    if ((vec->x == 0.0f) && (vec->z == 0.0f)) {
        sph.yaw = 0;
    } else {
        sph.yaw = DEGF_TO_BINANG(RADF_TO_DEGF(Math_atan2f(vec->x, vec->z)));
    }

    *dest = sph;

    return dest;
}

/**
 * Takes the point `vec`, and converts it to a geographic coordinate
 */
VecSph* OLib_Vec3fToVecSphGeo(VecSph* dest, Vec3f* vec) {
    VecSph sph;

    OLib_Vec3fToVecSph(&sph, vec);
    sph.pitch = 0x3FFF - sph.pitch;

    *dest = sph;

    return dest;
}

/**
 * Takes the differences of positions `a` and `b`, and converts them to spherical coordinates
 */
VecSph* OLib_Vec3fDiffToVecSph(VecSph* dest, Vec3f* a, Vec3f* b) {
    Vec3f sph;

    sph.x = b->x - a->x;
    sph.y = b->y - a->y;
    sph.z = b->z - a->z;

    return OLib_Vec3fToVecSph(dest, &sph);
}

/**
 * Takes the difference of positions `a` and `b`, and converts them to geographic coordinates
 */
VecSph* OLib_Vec3fDiffToVecSphGeo(VecSph* dest, Vec3f* a, Vec3f* b) {
    Vec3f sph;

    sph.x = b->x - a->x;
    sph.y = b->y - a->y;
    sph.z = b->z - a->z;

    return OLib_Vec3fToVecSphGeo(dest, &sph);
}

/**
 * Gets the pitch/yaw of the vector formed from `b`-`a`, result is in radians
 */
Vec3f* OLib_Vec3fDiffRad(Vec3f* dest, Vec3f* a, Vec3f* b) {
    Vec3f anglesRad;

    anglesRad.x = Math_atan2f(b->z - a->z, b->y - a->y);
    anglesRad.y = Math_atan2f(b->x - a->x, b->z - a->z);
    anglesRad.z = 0;

    *dest = anglesRad;

    return dest;
}

/**
 * Gets the pitch/yaw of the vector formed from `b`-`a`, result is in degrees
 */
Vec3f* OLib_Vec3fDiffDegF(Vec3f* dest, Vec3f* a, Vec3f* b) {
    Vec3f anglesRad;
    Vec3f anglesDegrees;

    OLib_Vec3fDiffRad(&anglesRad, a, b);

    anglesDegrees.x = RADF_TO_DEGF(anglesRad.x);
    anglesDegrees.y = RADF_TO_DEGF(anglesRad.y);
    anglesDegrees.z = 0.0f;

    *dest = anglesDegrees;

    return dest;
}

/**
 * Gets the pitch/yaw of the vector formed from `b`-`a`, result is in binary degrees
 */
Vec3s* OLib_Vec3fDiffBinAng(Vec3s* dest, Vec3f* a, Vec3f* b) {
    Vec3f anglesRad;
    Vec3s anglesBinAng;

    OLib_Vec3fDiffRad(&anglesRad, a, b);

    anglesBinAng.x = DEGF_TO_BINANG(RADF_TO_DEGF(anglesRad.x));
    anglesBinAng.y = DEGF_TO_BINANG(RADF_TO_DEGF(anglesRad.y));
    anglesBinAng.z = 0.0f;

    *dest = anglesBinAng;

    return dest;
}
