#!/usr/bin/python3
##
## This file is part of the sigrok-util project.
##
## Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
##
## This program is free software: you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published by
## the Free Software Foundation, either version 3 of the License, or
## (at your option) any later version.
##
## This program is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
## GNU General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with this program.  If not, see <http://www.gnu.org/licenses/>.
##

import os
import sys
import tempfile
from subprocess import Popen, PIPE
import shutil
import re
import socket
import datetime

TMPL_AUTOCONF_DRIVER = "DRIVER([${name}], [${short}])\n"
TMPL_AUTOCONF_DRIVER2 = "DRIVER2([HW_${upper}], [$HW_${upper}], [HAVE_HW_${upper}])\n"

TMPL_HWMAKE_DRIVERLIB = """if HW_${upper}
libsigrok_la_SOURCES += \\
	src/hardware/${short}/protocol.h \\
	src/hardware/${short}/protocol.c \\
	src/hardware/${short}/api.c
endif
"""
TMPL_DRIVERS_EXTERN = """\
#ifdef HAVE_HW_${upper}
extern SR_PRIV struct sr_dev_driver ${lib}_driver_info;
#endif
"""
TMPL_DRIVERS_POINTER = """\
#ifdef HAVE_HW_${upper}
	&${lib}_driver_info,
#endif
"""
FILE_DRV_API = 'drv-api.c'
FILE_DRV_PROTOCOL = 'drv-protocol.c'
FILE_DRV_PROTOCOL_H = 'drv-protocol.h'

def tmpl(template):
    out = re.sub(r'\${([^}]+)}', lambda x: str(names[x.group(1)]), template)

    return out


def tmpl_file(filename):
    template = open(TMPLDIR + '/' + filename).read()

    return tmpl(template)


def new_driver():
    tmp = tempfile.mkdtemp()
    try:
        os.chdir(tmp)
        process = Popen("git clone " + LIBSR, shell=True, stderr=PIPE)
        out, err = process.communicate()
        if process.returncode:
            raise Exception(err.decode())
        gitdir = tmp + '/libsigrok/'
        do_autoconf(gitdir)
        do_drivers(gitdir)
        do_automake(gitdir)
        do_driverskel(gitdir)
        make_patch(gitdir)
    except Exception as e:
        print(e)
    shutil.rmtree(tmp)


# add DRIVER and DRIVER2 entries to configure.ac
def do_autoconf(gitdir):
    cacpath = gitdir + 'configure.ac'
    configure_ac = open(cacpath).read()

    out = ''
    state = 'driver'
    active = False
    for line in configure_ac.split('\n')[:-1]:
        if state == 'driver':
            m = re.match('DRIVER\(\[([^\]]+)', line)
            if m:
                active = True
            if active:
                if (m and m.group(1).upper() > names['name'].upper()) or m is None:
                    out += tmpl(TMPL_AUTOCONF_DRIVER)
                    state = 'automake'
                    active = False
        elif state == 'automake':
            m = re.match('DRIVER2\(\[([^\]]+)', line)
            if m:
                active = True
            else:
                submatch = re.match('DRIVER2\(\[([^\]]+)', line)
                if active and submatch is None:
                    # we're past the DRIVER2 list
                    out += tmpl(TMPL_AUTOCONF_DRIVER2)
                    state = 'done'
            if active:
                if (m and m.group(1) > 'HW_' + names['upper']):
                    out += tmpl(TMPL_AUTOCONF_DRIVER2)
                    state = 'done'
        out += line + '\n'
    if state != 'done':
        raise Exception('No DRIVER entries found in configure.ac')
    open(cacpath, 'w').write(out)


# add HAVE_HW_ extern and pointers to drivers.c
def do_drivers(gitdir):
    path = gitdir + 'src/drivers.c'
    source = open(path).read()
    out = ''
    state = 'extern'
    first_entry = ''
    for line in source.split('\n')[:-1]:
        m = re.match('#ifdef HAVE_HW_(.*)', line)
        if m:
            if not first_entry:
                first_entry = m.group(1)
            elif m.group(1) == first_entry:
                # second time we see this, so we're past the externs
                if state != 'idle':
                    # tack driver on to the end of the list
                    out += tmpl(TMPL_DRIVERS_EXTERN)
                state = 'pointer'
            if state == 'extern':
                if m.group(1) > names['upper']:
                    out += tmpl(TMPL_DRIVERS_EXTERN)
                    state = 'idle'
            elif state == 'pointer':
                if m.group(1) > names['upper']:
                    out += tmpl(TMPL_DRIVERS_POINTER)
                    state = 'done'
        elif state == 'pointer' and not re.match('(\s*&|#endif|$)', line):
            # we passed the last entry
            out += tmpl(TMPL_DRIVERS_POINTER)
            state = 'done'
        out += line + '\n'
    if state != 'done':
        raise Exception('No "HAVE_HW_*" markers found in drivers.c' + state)
    open(path, 'w').write(out)


# add HW_ entry to Makefile.am
def do_automake(gitdir):
    path = gitdir + 'Makefile.am'
    hwmake = open(path).read()

    out = ''
    state = 'copy'
    for line in hwmake.split('\n')[:-1]:
        if state == 'copy' and re.match('if HW_(.*)$', line):
            state = 'drivers'
        if state == 'drivers':
            m = re.match('if HW_(.*)$', line)
            if m:
                drv_short = m.group(1)
                if drv_short > names['upper']:
                    out += tmpl(TMPL_HWMAKE_DRIVERLIB)
                    state = 'done'
            elif not re.match('(libsigrok_la_SOURCES|\s*src/hardware/|endif)', line):
                print("[%s]" % line.strip())
                # we passed the last entry
                out += tmpl(TMPL_HWMAKE_DRIVERLIB)
                state = 'done'
        out += line + '\n'
    if state != 'done':
        raise Exception('No "if HW_" markers found in Makefile.am')
    open(path, 'w').write(out)


def do_driverskel(gitdir):
    drvdir = gitdir + 'src/hardware/' + names['short']
    os.mkdir(drvdir)
    open(drvdir + '/api.c', 'w').write(tmpl_file(FILE_DRV_API))
    open(drvdir + '/protocol.c', 'w').write(tmpl_file(FILE_DRV_PROTOCOL))
    open(drvdir + '/protocol.h', 'w').write(tmpl_file(FILE_DRV_PROTOCOL_H))


def make_patch(gitdir):
    os.chdir(gitdir)
    command('git add src/hardware/' + names['short'])
    cmd = 'git commit -m "%s: Initial driver skeleton." ' % names['short']
    cmd += 'configure.ac Makefile.am src/drivers.c src/hardware/' + names['short']
    command(cmd)
    cmd = "git format-patch HEAD~1"
    out, err = Popen(cmd, shell=True, stdout=PIPE, stderr=PIPE).communicate()
    if err:
        raise Exception(err.decode())
    patch = out.decode().strip()
    shutil.move(gitdir + '/' + patch, scriptdir + '/' + patch)
    print(patch)


def command(cmd):
    out, err = Popen(cmd, shell=True, stderr=PIPE).communicate()
    if err:
        raise Exception(err.decode())


def parse_gitconfig():
    try:
        author = email = None
        for line in open(os.environ['HOME'] + '/.gitconfig').readlines():
            m = re.match('\s*(\w+)\s*=\s*(.*)\s*$', line)
            if m:
                key, value = m.groups()
                if key == 'name':
                    author = value
                elif key == 'email':
                    email = value
                if author and email:
                    break
    except:
        pass
    if not author or not email:
        print("Please put your name and email in ~/.gitconfig")
        sys.exit()

    return author, email

#
# main
#

scriptdir = os.getcwd()
if scriptdir.split('/')[-2:] != ['sigrok-util', 'source']:
	print("Please call this script from the 'source' directory.")
	sys.exit(1)

LIBSR = 'git://sigrok.org/libsigrok'
TMPLDIR = scriptdir

if len(sys.argv) < 2:
    print("Usage: new-driver <name>")
    sys.exit()

author, email = parse_gitconfig()
name = ' '.join(sys.argv[1:])
names = {
    'name': name,
    'short': re.sub('[^a-z0-9]', '-', name.lower()),
    'lib': re.sub('[^a-z0-9]', '_', name.lower()),
    'upper': re.sub('[^A-Z0-9]', '_', name.upper()),
    'libupper': re.sub('[^A-Z0-9]', '', name.upper()),
    'year': datetime.datetime.now().year,
    'author': author,
    'email': email,
}
new_driver()