#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include <math.h>
#include <complex.h>
#include <string.h>

#include "../numeric/SU21-numeric.h"
#include "../numeric/SU21-numeric-base.c"

#define GOODPREFIX "C18/C18-0"

/* Square root of 6 */
#define sq6 (2.449489742783178098197284074706)
/* 3rd root of unity */
#define z3 (-0.5+.866025403784438646763723170753*I)
#define om z3

// The original generators act unitarily with respect to the
// form $\diag(1,1,-(\sqrt{6}-2))=\diag(1,1,-R_0^2)$.

// R0 =$\sqrt(\sqrt(6)-2))$
#define R0 (0.6704399621018858226912370073194)

typedef struct {
  char Nam[MaxGenNameLength+1]; // Generator name
  char InvNam[MaxGenNameLength+1]; // Inverse generator name
  int Len; // ``Length'' of Generator
  Mtx_t Mtx; // matrix for generator
} Gen_t;

#define MaxNoGens 3
#define ActualNoGens 3
#define KSiz 1

void SetupGens(Elt_t GenElts[],int *NoGenElts_p);
void SetupK(Elt_t KElts[]);

int main(int argc,char *(argv[])) {
  // The generators as group elements
  Elt_t GenElts[2*ActualNoGens],KElts[KSiz];

  char *Prefix_p,FileNam[MAX_FILENAME_LEN]="../";
  int GenIx,GenEltIx,NoGenElts;
  size_t NamLen;
  Mtx_t MtxInv;

  FILE *GensFile;
  FILE *KFile;

  // Check that the prefix is right
  Prefix_p=getenv("PREFIX");
  assert(Prefix_p != NULL);
  assert(strncmp(Prefix_p,GOODPREFIX,50) == 0);

  // Open the output files
  {
    size_t len=strlen(Prefix_p);
    assert(3+len+5<MAX_FILENAME_LEN);
    strcpy(&FileNam[3],Prefix_p);
    strcpy(&FileNam[3]+len,"-Gens");
    printf("%s\n",FileNam);
    GensFile=fopen(FileNam,"w");
    assert(GensFile != NULL);
    strcpy(&FileNam[3]+len,"-K");
    printf("%s\n",FileNam);
    KFile=fopen(FileNam,"w");
    assert(KFile != NULL);
  }

  // Prepare the generators and write the generator file
  SetupGens(GenElts,&NoGenElts);
  fprintf(GensFile,"NoGenElts=%i\n",NoGenElts);
  for(GenEltIx=0;GenEltIx<NoGenElts;GenEltIx++)
    OutputElt(GensFile,GenElts[GenEltIx]);

  // Prepare K (the finite group) and write the K file
  SetupK(KElts);
  fprintf(KFile,"KSiz=%i\n",KSiz);
  for(GenEltIx=0;GenEltIx<KSiz;GenEltIx++)
    OutputElt(KFile,KElts[GenEltIx]);
}

// Prepare the generating elements
//
void SetupGens(Elt_t GenElts[],int *NoGenElts_p) {
  // The form with respect to which the original, given matrices are
  // unitary:
  Mtx_t FF0=
    {{ 1, 0,    0  },
     { 0, 1,    0  },
     { 0, 0, -R0*R0}};

  // Matrix by which to conjugate them to make them unitary with
  // respect to $\diag{1,1,-1}$
  Mtx_t ConjMtxInv, ConjMtx={
    { 1, 0,  0},
    { 0, 1,  0},
    { 0, 0, R0}};

  // The generators
  Gen_t Gens[MaxNoGens]={
    {"U","u",2,
     {{ sq6*(om-1)/6, sq6*(om-1)/6, 0}, 
      {-sq6*(om-1)/6, sq6*(om-1)/6, 0}, 
      {          0,          0, 1}}
    },

    {"V","v",200,
     {{1,  0, 0}, 
      {0, -1, 0}, 
      {0,  0, 1}}
    },

    {"A","a",1000,
     {{1/3.0*sq6*om+1/3.0*(2*sq6+3),0,-1/3.0*sq6*om+1/3.0*sq6},
      {0,1,0},
      {1/3.0*(-2*sq6-6)*om+1/3.0*(-sq6-3),0,1/3.0*(-sq6-3)*om+1/3.0*(-2*sq6-3)}
     }
    }
  };

  int GenIx,GenEltIx;
  size_t NamLen;
  Mtx_t MtxInv;

  // Calculate the inverse of ConjMtx
  InvMtx(ConjMtxInv,ConjMtx);
  
  GenEltIx=0;
  for(GenIx=0;GenIx<ActualNoGens;GenIx++) {
    // Check that the matrix is unitary with respect to FF0
    // printf("Checking GenIx=%i\n",GenIx);
    assert(CheckUnitary(Gens[GenIx].Mtx,FF0));
    // Calculate the conjugated matrix
    ConjugateMtx(GenElts[GenEltIx].Mtx,Gens[GenIx].Mtx,ConjMtx,ConjMtxInv);
    // and check that that is unitary relative to FF1
    assert(CheckUnitary(GenElts[GenEltIx].Mtx,FF1));
    InvMtx(MtxInv,GenElts[GenEltIx].Mtx);
    // Set up the generator name
    NamLen=strlen(Gens[GenIx].Nam);
    assert(NamLen>0 && NamLen<MaxGenNameLength);
    strcpy(GenElts[GenEltIx].Word,Gens[GenIx].Nam);
    // and ``length''
    GenElts[GenEltIx].Len=Gens[GenIx].Len;
    // and KIx and KStart
    GenElts[GenEltIx].KIx = -1;
    GenElts[GenEltIx].KStart = 0;
    
    FixUpElt(&GenElts[GenEltIx]);
    GenEltIx++;

    // Now do the inverse generator.  If the inverse name is empty, we
    // skip this.
    NamLen=strlen(Gens[GenIx].InvNam);
    if(NamLen>0) {
      // The matrix
      memcpy(&GenElts[GenEltIx].Mtx,MtxInv,sizeof(Mtx_t));
      assert(CheckUnitary(GenElts[GenEltIx].Mtx,FF1));
      // the inverse generator name
      assert(NamLen<MaxGenNameLength);
      strcpy(GenElts[GenEltIx].Word,Gens[GenIx].InvNam);
      // the length
      GenElts[GenEltIx].Len=Gens[GenIx].Len;
      // and KIx and KStart
      GenElts[GenEltIx].KIx = -1;
      GenElts[GenEltIx].KStart = 0;

      FixUpElt(&GenElts[GenEltIx]);
      GenEltIx++;
    }
  }
  *NoGenElts_p=GenEltIx;
}

// Set up the (trivial) finite group, K
//
void SetupK(Elt_t KElts[]) {
  // The identity element
  Gen_t IGen=
    {"1","",0,{{1,0,0},{0,1,0},0,0,1}};
  Elt_t *KElt_p;

  KElt_p=&KElts[0];

  // Set up the matrix
  memcpy(KElt_p->Mtx,IGen.Mtx,sizeof(Mtx_t));
  // the generator name
  assert(strlen(IGen.Nam)<MaxGenNameLength);
  strcpy(KElt_p->Word,IGen.Nam);
  // the ``length''
  KElt_p->Len = IGen.Len;
  // and KIx and KStart
  KElt_p->KIx = 0;
  KElt_p->KStart = 0;

  FixUpElt(KElt_p);
}