#! /usr/bin/python3
import os.path
import sys
import shlex
import re

from headerutils import *


tabstop = 2
padding = "                                                                  "
seen = { }
output = list()
summary = list()
sawcore = False

# list of headers to emphasize
highlight = list ()

bld_dir = ""
# search path for headers
incl_dirs = ["../include", "../libcpp/include", "common", "c-family", "c", "cp", "config" ]
# extra search paths to look in *after* the directory the source file is in. 

# append (1) to the end of the first line which includes INC in list INC.
def append_1 (output, inc):
  for n,t in enumerate (output):
    idx = t.find(inc)
    if idx != -1:
      eos = idx + len (inc)
      t = t[:eos] + "  (1)" + t[eos+1:]
      output[n] = t
      return

# These headers show up as duplicates in rtl.h due to conditional code arund the includes
rtl_core = [ "machmode.h" , "signop.h" , "wide-int.h" , "double-int.h" , "real.h" , "fixed-value.h" , "statistics.h" , "vec.h" , "hash-table.h" , "hash-set.h" , "input.h" , "is-a.h" ]

def find_include_data (inc):
  global sawcore
  for x in incl_dirs:
    nm = x+"/"+inc
    if os.path.exists (nm):
      info = find_unique_include_list (nm)
      # rtl.h mimics coretypes for GENERATOR FILES, remove if coretypes.h seen.
      if inc == "coretypes.h":
        sawcore = True
      elif inc  == "rtl.h" and sawcore:
        for i in rtl_core:
          if i in info:
            info.remove (i)
      return info
  return list()

def process_include (inc, indent):
  if inc[-2:] != ".h":
    return
  bname  = os.path.basename (inc)
  if bname in highlight:
    arrow = "                <<-------"
    if bname not in summary:
      summary.append (bname)
  else:
    arrow = ""
  if seen.get(inc) == None:
    seen[inc] = 1
    output.append (padding[:indent*tabstop] + bname + arrow)
    info = find_include_data (inc)
    for y in info:
      process_include (y, indent+1)
  else:
    seen[inc] += 1
    if (seen[inc] == 2):
      append_1(output, inc)
    output.append (padding[:indent*tabstop] + bname + "  ("+str(seen[inc])+")" + arrow)

    

extradir = list()
usage = False
src = list()

for x in sys.argv[1:]:
  if x[0:2] == "-i":
    bld = x[2:]
    extradir.append (bld)
  elif x[0:2] == "-s":
    highlight.append (os.path.basename (x[2:]))
  elif x[0:2] == "-h":
    usage = True
  else:
    src.append (x)

if len(src) != 1:
  usage = True
elif not os.path.exists (src[0]):
  print (src[0] + ": Requested source file does not exist.\n")
  usage = True

if usage:
  print ("show-headers [-idir] [-sfilen] file1 ")
  print (" ")
  print (" Show a hierarchical visual format how many times each header file")
  print (" is included in a source file.  Should be run from the source directory")
  print (" files from find-include-depends")
  print ("      -s : search for a header, and point it out.")
  print ("      -i : Specifies additonal directories to search for includes.")
  sys.exit(0)



if extradir:
  incl_dirs = extradir + incl_dirs;

blddir = find_gcc_bld_dir ("../..")

if blddir:
  print ("Using build directory: " + blddir)
  incl_dirs.insert (0, blddir)
else:
  print ("Could not find a build directory, better results if you specify one with -i")

# search path is now ".", blddir, extradirs_from_-i, built_in_incl_dirs
incl_dirs.insert (0, ".")

# if source is in a subdirectory, prepend the subdirectory to the search list
x = src[0]
srcpath = os.path.dirname(x)
if srcpath:
  incl_dirs.insert (0, srcpath)

output = list()
sawcore = False

data = open (x).read().splitlines()
for line in data:
  d = find_pound_include (line, True, True)
  if d and d[-2:] == ".h":
    process_include (d, 1)

print ("\n" + x)
for line in output:
  print (line)

if highlight:
  print (" ")
  for h in summary:
    print (h + " is included by source file.")
  for h in highlight:
    if h not in summary:
      print (h + " is not included by source file.")