#!/usr/bin/python

import os,sys,re,string

def die(s):
    sys.stderr.write(s)
    sys.exit(1)
def run(s):
    sys.stderr.write("# "+s+"\n")
    return os.system(s)
def tick(s):
    return os.popen(s,"r").read()

file = sys.argv[-1]
rest = sys.argv[1:-1]

temp = "___temp___.cc"
tempo = "___temp___.o"

def clean():
    try: os.remove(temp)
    except: pass
    try: os.remove(tempo)
    except: pass

run("cp %s %s"%(file,temp))
if run("gcc %s -c %s"%(string.join(rest),temp))!=0:
    die("simple compile fails")
checksum = tick("md5sum %s"%tempo)

lines = open(file,"r").readlines()

includes = []
for i in range(len(lines)):
    if re.search(r'^\s*#\s*include',lines[i]):
        includes.append(i)

def write_skipping(file,lines,skips,soft=0):
    stream = open(file,"w")
    for i in range(len(lines)):
        line = lines[i]
        if i in skips:
            if not soft:
                stream.write("// "+line)
            else:
                stream.write(line+" // NOT NEEDED")
        else:
            stream.write(line)
    stream.close()

skips = []
for k in range(len(includes)):
    clean()
    testcase = []
    write_skipping("___temp___.cc",lines,skips+[includes[k]])
    if run("gcc %s -c %s"%(string.join(rest),temp))==0:
        nchecksum = tick("md5sum %s"%tempo)
        if checksum!=nchecksum:
            print "WARNING checksum changed for ",lines[includes[k]][:-1]
        else:
            print "REMOVING",lines[includes[k]][:-1]
            skips.append(includes[k])

clean()

if skips!=[]:
    write_skipping(file+".new",lines,skips,os.getenv("fixstyle")=="soft")
    if os.getenv("fixincludes")=="modify":
        os.rename(file,file+".before-fix-includes") 
        os.rename(file+".new",file)