#!/bin/sh

str=$(cat $1 | perl -pe 's|\[G\^(.*?)_(.*?)\]|G\2|' |\
	perl -pe 's|\[alpha_s/pi\]|1/pi|' |\
	perl -pe 's|NF|N_c|g' |\
	perl -pe 's|\[ln\((.*?)\)\]|Log[\1]|g' |\
	perl -pe 's|Log\[\(v(\d+).n\)\^2\/n\^2\]|log(nu\1)|g' |\
	perl -pe 's|v(\d+).v(\d+)|v\1\2|g' |\
	perl -pe 's|\[L_beta_(.*?)\]|L_beta_\1|g' |\
	perl -pe 's|Log\[(.*?)\]|log(\1)|g' |\
	perl -pe 's|;|"""|'| perl -pe 's|   ||' |\
	perl -pe 's|=\n?|="""|' \
)

vars=$(echo "$str" | grep -o ".*=")
add_vars=$(echo "$vars" | perl -pe 's|(.*?)=|var.append((\1,"\1"))|')

echo "import sympy as sy" > simp.py
echo "import re" >> simp.py
echo "import subprocess" >> simp.py
cat <<EOF >>simp.py
def runFORM(expr):
    expr = str(expr)
    expr = re.sub('L_beta_',r"Lbeta",expr)
    expr = re.sub('N_c',r"Nc",expr)
    expr = re.sub('I',r"i_",expr)
    code = '''\
#-
off stats;

S Nc, pi, s, MT;
Auto S Lbeta;
Auto S nu, v;
CF log;

L expr = {0};

.sort
AB Nc;
Print;
.end
'''.format(expr)

    form_file_name = '/tmp/FORM_Code.frm'
    with open(form_file_name,'w') as f:
        f.write(code)

    form_res = subprocess.run(["form","-f",form_file_name],capture_output=True,text=True).stdout
    form_res=form_res.replace('\n','')
    form_res=form_res.replace(' ','')
    form_res=form_res.replace(';','')
    form_res=form_res.replace('expr=','')
    form_res=form_res.replace('Nc','N_c')
    form_res=form_res.replace('Lbeta','L_beta')
    form_res=form_res.replace('i_','I')
    form_res=form_res.replace('MT',r"m_t")
    return form_res
EOF
echo "$str" >> simp.py
cat <<EOF >> simp.py
var = list()
pi = sy.pi
a = sy.Symbol('alpha_s')
Nc = sy.Symbol('N_c')
EOF
echo "$add_vars" >> simp.py
cat <<EOF >> simp.py
res = list()
for v in var:
    #expr = sy.fraction(sy.sympify(v[0]).simplify())
    expr = (sy.sympify(v[0]).expand()*2*pi).simplify()
    #expr = sy.fraction(2*sy.sympify(v[0]).collect(pi))
    expr = sy.sympify(runFORM(expr)).simplify()
    expr = sy.fraction(expr)
    num = expr[0]
    for i in range(10):
        num=sy.collect(num,Nc**2-i)
        num=sy.collect(num,Nc-i)
        num=sy.collect(num,Nc+i)
    num=sy.collect(num,-Nc*(Nc-1)+2)
    num=sy.collect(num,Nc*(Nc+1)-2)
    if(len(num.args)==2):
        pre = sy.latex(num.args[0]/expr[1])
        num = num.args[1]
    elif(expr[1] != 1):
        pre = sy.latex(1/expr[1])
    else:
        pre = ''
    g=re.sub('G(\d+)x(\d+)',r"\\\\Gamma^{(1)}_{\1,\2}",v[1])
    prefact = sy.latex(a/(2*pi))
    prefact = ''
    if(pre!=''):
	    rhs =  prefact+pre+'\\\\breaktowidth{0.9\\\\linewidth}{\\\\delimiterswithbreaks{[}{]}{'
    else:
        rhs =  '\\\\breaktowidth{0.9\\\\linewidth}{'
    #rhs += re.sub(r"\\\\left\\((.*)\\\\right\\)",r"\\\\delimiterswithbreaks{(}{)}{\1}",sy.latex(num))
    rhs += sy.latex(num)
    if(pre!=''):
        rhs += '}}'
    else:
        rhs += '}'
    if num == 0:
        rhs = 0

    print("{0}=&{1}\\\\nonumber \\\\\\\\".format(g,rhs))
EOF

ipython simp.py > result.txt