#!/usr/bin/env python3
##
## This file is part of the sigrok-test project.
##
## Copyright (C) 2013 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 re
from getopt import getopt
from tempfile import mkstemp
from subprocess import Popen, PIPE
from difflib import Differ
from hashlib import md5
from shutil import copy

DEBUG = 0
VERBOSE = False


class E_syntax(Exception):
    pass
class E_badline(Exception):
    pass

def INFO(msg, end='\n'):
    if VERBOSE:
        print(msg, end=end)
        sys.stdout.flush()


def DBG(msg):
    if DEBUG:
        print(msg)


def ERR(msg):
    print(msg, file=sys.stderr)


def usage(msg=None):
    if msg:
        print(msg.strip() + '\n')
    print("""Usage: testpd [-dvalsrfcR] [<test1> <test2> ...]
  -d  Turn on debugging
  -v  Verbose
  -a  All tests
  -l  List test(s)
  -s  Show test(s)
  -r  Run test(s)
  -f  Fix failed test(s) / create initial output for new test(s)
  -c  Report decoder code coverage
  -R <directory>  Save test reports to <directory>
  <test>  Protocol decoder name ("i2c") and optionally test name ("i2c/rtc")""")
    sys.exit()


def check_tclist(tc):
    if 'pdlist' not in tc or not tc['pdlist']:
        return("No protocol decoders")
    if 'input' not in tc or not tc['input']:
        return("No input")
    if 'output' not in tc or not tc['output']:
        return("No output")
    for op in tc['output']:
        if 'match' not in op:
            return("No match in output")

    return None


def parse_testfile(path, pd, tc, op_type, op_class):
    DBG("Opening '%s'" % path)
    tclist = []
    for line in open(path).read().split('\n'):
        try:
            line = line.strip()
            if len(line) == 0 or line[0] == "#":
                continue
            f = line.split()
            if not tclist and f[0] != "test":
                # That can't be good.
                raise E_badline
            key = f.pop(0)
            if key == 'test':
                if len(f) != 1:
                    raise E_syntax
                # new testcase
                tclist.append({
                    'pd': pd,
                    'name': f[0],
                    'pdlist': [],
                    'output': [],
                })
            elif key == 'protocol-decoder':
                if len(f) < 1:
                    raise E_syntax
                pd_spec = {
                    'name': f.pop(0),
                    'channels': [],
                    'options': [],
                    'initial_pins': [],
                }
                while len(f):
                    if len(f) == 1:
                        # Always needs <key> <value>
                        raise E_syntax
                    a, b = f[:2]
                    f = f[2:]
                    if '=' not in b:
                        raise E_syntax
                    opt, val = b.split('=')
                    if a == 'channel':
                        try:
                            val = int(val)
                        except:
                            raise E_syntax
                        pd_spec['channels'].append([opt, val])
                    elif a == 'option':
                        pd_spec['options'].append([opt, val])
                    elif a == 'initial_pin':
                        try:
                            val = int(val)
                        except:
                            raise E_syntax
                        pd_spec['initial_pins'].append([opt, val])
                    else:
                        raise E_syntax
                tclist[-1]['pdlist'].append(pd_spec)
            elif key == 'stack':
                if len(f) < 2:
                    raise E_syntax
                tclist[-1]['stack'] = f
            elif key == 'input':
                if len(f) != 1:
                    raise E_syntax
                tclist[-1]['input'] = f[0]
            elif key == 'output':
                op_spec = {
                    'pd': f.pop(0),
                    'type': f.pop(0),
                }
                while len(f):
                    if len(f) == 1:
                        # Always needs <key> <value>
                        raise E_syntax
                    a, b = f[:2]
                    f = f[2:]
                    if a == 'class':
                        op_spec['class'] = b
                    elif a == 'match':
                        op_spec['match'] = b
                    else:
                        raise E_syntax
                tclist[-1]['output'].append(op_spec)
            else:
                raise E_badline
        except E_badline as e:
            ERR("Invalid syntax in %s: line '%s'" % (path, line))
            return []
        except E_syntax as e:
            ERR("Unable to parse %s: unknown line '%s'" % (path, line))
            return []

    # If a specific testcase was requested, keep only that one.
    if tc is not None:
        target_tc = None
        for t in tclist:
            if t['name'] == tc:
                target_tc = t
                break
        # ...and a specific output type
        if op_type is not None:
            target_oplist = []
            for op in target_tc['output']:
                if op['type'] == op_type:
                    # ...and a specific output class
                    if op_class is None or ('class' in op and op['class'] == op_class):
                        target_oplist.append(op)
                        DBG("match on [%s]" % str(op))
            target_tc['output'] = target_oplist
        if target_tc is None:
            tclist = []
        else:
            tclist = [target_tc]
    for t in tclist:
        error = check_tclist(t)
        if error:
            ERR("Error in %s: %s" % (path, error))
            return []

    return tclist


def get_tests(testnames):
    tests = {}
    for testspec in testnames:
        # Optional testspec in the form pd/testcase/type/class
        tc = op_type = op_class = None
        ts = testspec.strip("/").split("/")
        pd = ts.pop(0)
        tests[pd] = []
        if ts:
            tc = ts.pop(0)
        if ts:
            op_type = ts.pop(0)
        if ts:
            op_class = ts.pop(0)
        path = os.path.join(tests_dir, pd)
        if not os.path.isdir(path):
            # User specified non-existent PD
            raise Exception("%s not found." % path)
        path = os.path.join(tests_dir, pd, "test.conf")
        if not os.path.exists(path):
            # PD doesn't have any tests yet
            continue
        tests[pd].append(parse_testfile(path, pd, tc, op_type, op_class))

    return tests


def diff_text(f1, f2):
    t1 = open(f1).readlines()
    t2 = open(f2).readlines()
    diff = []
    d = Differ()
    for line in d.compare(t1, t2):
        if line[:2] in ('- ', '+ '):
            diff.append(line.strip())

    return diff


def compare_binary(f1, f2):
    h1 = md5()
    h1.update(open(f1, 'rb').read())
    h2 = md5()
    h2.update(open(f2, 'rb').read())
    if h1.digest() == h2.digest():
        result = None
    else:
        result = ["Binary output does not match."]

    return result


# runtc's stdout can have lines like:
# coverage: lines=161 missed=2 coverage=99%
def parse_stats(text):
    stats = {}
    for line in text.strip().split('\n'):
        fields = line.split()
        key = fields.pop(0).strip(':')
        if key not in stats:
            stats[key] = []
        stats[key].append({})
        for f in fields:
            k, v = f.split('=')
            stats[key][-1][k] = v

    return stats


# take result set of all tests in a PD, and summarize which lines
# were not covered by any of the tests.
def coverage_sum(cvglist):
    lines = 0
    missed = 0
    missed_lines = {}
    for record in cvglist:
        lines = int(record['lines'])
        missed += int(record['missed'])
        if 'missed_lines' not in record:
            continue
        for linespec in record['missed_lines'].split(','):
            if linespec not in missed_lines:
                missed_lines[linespec] = 1
            else:
                missed_lines[linespec] += 1

    # keep only those lines that didn't show up in every non-summary record
    final_missed = []
    for linespec in missed_lines:
        if missed_lines[linespec] != len(cvglist):
            continue
        final_missed.append(linespec)

    return lines, final_missed


def run_tests(tests, fix=False):
    errors = 0
    results = []
    cmd = [os.path.join(runtc_dir, 'runtc')]
    if opt_coverage:
        fd, coverage = mkstemp()
        os.close(fd)
        cmd.extend(['-c', coverage])
    else:
        coverage = None
    for pd in sorted(tests.keys()):
        pd_cvg = []
        for tclist in tests[pd]:
            for tc in tclist:
                args = cmd[:]
                if DEBUG > 1:
                    args.append('-d')
                # Set up PD stack for this test.
                for spd in tc['pdlist']:
                    args.extend(['-P', spd['name']])
                    for label, channel in spd['channels']:
                        args.extend(['-p', "%s=%d" % (label, channel)])
                    for option, value in spd['options']:
                        args.extend(['-o', "%s=%s" % (option, value)])
                    for label, initial_pin in spd['initial_pins']:
                        args.extend(['-N', "%s=%d" % (label, initial_pin)])
                args.extend(['-i', os.path.join(dumps_dir, tc['input'])])
                for op in tc['output']:
                    name = "%s/%s/%s" % (pd, tc['name'], op['type'])
                    opargs = ['-O', "%s:%s" % (op['pd'], op['type'])]
                    if 'class' in op:
                        opargs[-1] += ":%s" % op['class']
                        name += "/%s" % op['class']
                    if VERBOSE:
                        dots = '.' * (77 - len(name) - 2)
                        INFO("%s %s " % (name, dots), end='')
                    results.append({
                        'testcase': name,
                    })
                    try:
                        fd, outfile = mkstemp()
                        os.close(fd)
                        opargs.extend(['-f', outfile])
                        DBG("Running %s" % (' '.join(args + opargs)))
                        p = Popen(args + opargs, stdout=PIPE, stderr=PIPE)
                        stdout, stderr = p.communicate()
                        if stdout:
                            # statistics and coverage data on stdout
                            results[-1].update(parse_stats(stdout.decode('utf-8')))
                        if stderr:
                            results[-1]['error'] = stderr.decode('utf-8').strip()
                            errors += 1
                        elif p.returncode != 0:
                            # runtc indicated an error, but didn't output a
                            # message on stderr about it
                            results[-1]['error'] = "Unknown error: runtc %d" % p.returncode
                        if 'error' not in results[-1]:
                            matchfile = os.path.join(tests_dir, op['pd'], op['match'])
                            DBG("Comparing with %s" % matchfile)
                            try:
                                diff = diff_error = None
                                if op['type'] in ('annotation', 'python'):
                                    diff = diff_text(matchfile, outfile)
                                elif op['type'] == 'binary':
                                    diff = compare_binary(matchfile, outfile)
                                else:
                                    diff = ["Unsupported output type '%s'." % op['type']]
                            except Exception as e:
                                diff_error = e
                            if fix:
                                if diff or diff_error:
                                    copy(outfile, matchfile)
                                    DBG("Wrote %s" % matchfile)
                            else:
                                if diff:
                                    results[-1]['diff'] = diff
                                elif diff_error is not None:
                                    raise diff_error
                    except Exception as e:
                        results[-1]['error'] = str(e)
                    finally:
                        if coverage:
                            results[-1]['coverage_report'] = coverage
                        os.unlink(outfile)
                    if op['type'] == 'exception' and 'error' in results[-1]:
                        # filter out the exception we were looking for
                        reg = "^Error: srd: %s:" % op['match']
                        if re.match(reg, results[-1]['error']):
                            # found it, not an error
                            results[-1].pop('error')
                            errors -= 1
                    if VERBOSE:
                        if 'diff' in results[-1]:
                            INFO("Output mismatch")
                        elif 'error' in results[-1]:
                            error = results[-1]['error']
                            if len(error) > 20:
                                error = error[:17] + '...'
                            INFO(error)
                        elif 'coverage' in results[-1]:
                            # report coverage of this PD
                            for record in results[-1]['coverage']:
                                # but not others used in the stack
                                # as part of the test.
                                if record['scope'] == pd:
                                    INFO(record['coverage'])
                                    break
                        else:
                            INFO("OK")
                    gen_report(results[-1])
                    if coverage:
                        os.unlink(coverage)
                        # only keep track of coverage records for this PD,
                        # not others in the stack just used for testing.
                        for cvg in results[-1]['coverage']:
                            if cvg['scope'] == pd:
                                pd_cvg.append(cvg)
        if opt_coverage and len(pd_cvg) > 1:
            # report total coverage of this PD, across all the tests
            # that were done on it.
            total_lines, missed_lines = coverage_sum(pd_cvg)
            pd_coverage = 100 - (float(len(missed_lines)) / total_lines * 100)
            if VERBOSE:
                dots = '.' * (54 - len(pd) - 2)
                INFO("%s total %s %d%%" % (pd, dots, pd_coverage))
            if report_dir:
                # generate a missing lines list across all the files in
                # the PD
                files = {}
                for entry in missed_lines:
                    filename, line = entry.split(':')
                    if filename not in files:
                        files[filename] = []
                    files[filename].append(line)
                text = ''
                for filename in sorted(files.keys()):
                    line_list = ','.join(sorted(files[filename], key=int))
                    text += "%s: %s\n" % (filename, line_list)
                open(os.path.join(report_dir, pd + "_total"), 'w').write(text)


    return results, errors

def get_run_tests_error_diff_counts(results):
    """Get error and diff counters from run_tests() results."""
    errs = 0
    diffs = 0
    for result in results:
        if 'error' in result:
            errs += 1
        if 'diff' in result:
            diffs += 1
    return errs, diffs


def gen_report(result):
    out = []
    if 'error' in result:
        out.append("Error:")
        out.append(result['error'])
        out.append('')
    if 'diff' in result:
        out.append("Test output mismatch:")
        out.extend(result['diff'])
        out.append('')
    if 'coverage_report' in result:
        out.append(open(result['coverage_report'], 'r').read())
        out.append('')

    if out:
        text = "Testcase: %s\n" % result['testcase']
        text += '\n'.join(out)
    else:
        return

    if report_dir:
        filename = result['testcase'].replace('/', '_')
        open(os.path.join(report_dir, filename), 'w').write(text)
    else:
        print(text)


def show_tests(tests):
    for pd in sorted(tests.keys()):
        for tclist in tests[pd]:
            for tc in tclist:
                print("Testcase: %s/%s" % (tc['pd'], tc['name']))
                for pd in tc['pdlist']:
                    print("  Protocol decoder: %s" % pd['name'])
                    for label, channel in pd['channels']:
                        print("    Channel %s=%d" % (label, channel))
                    for option, value in pd['options']:
                        print("    Option %s=%s" % (option, value))
                    for label, initial_pin in pd['initial_pins']:
                        print("    Initial pin %s=%d" % (label, initial_pin))
                if 'stack' in tc:
                    print("  Stack: %s" % ' '.join(tc['stack']))
                print("  Input: %s" % tc['input'])
                for op in tc['output']:
                    print("  Output:\n    Protocol decoder: %s" % op['pd'])
                    print("    Type: %s" % op['type'])
                    if 'class' in op:
                        print("    Class: %s" % op['class'])
                    print("    Match: %s" % op['match'])
            print()


def list_tests(tests):
    for pd in sorted(tests.keys()):
        for tclist in tests[pd]:
            for tc in tclist:
                for op in tc['output']:
                    line = "%s/%s/%s" % (tc['pd'], tc['name'], op['type'])
                    if 'class' in op:
                        line += "/%s" % op['class']
                    print(line)


#
# main
#

# project root
runtc_dir = os.path.abspath(os.path.dirname(sys.argv[0]))
base_dir = os.path.abspath(os.path.join(os.curdir, runtc_dir, os.path.pardir))
dumps_dir = os.path.abspath(os.path.join(base_dir, os.path.pardir, 'sigrok-dumps'))
tests_dir = os.path.abspath(os.path.join(runtc_dir, 'test'))

if len(sys.argv) == 1:
    usage()

opt_all = opt_run = opt_show = opt_list = opt_fix = opt_coverage = False
report_dir = None
try:
    opts, args = getopt(sys.argv[1:], "dvarslfcR:S:")
except Exception as e:
    usage('error while parsing command line arguments: {}'.format(e))
for opt, arg in opts:
    if opt == '-d':
        DEBUG += 1
    if opt == '-v':
        VERBOSE = True
    elif opt == '-a':
        opt_all = True
    elif opt == '-r':
        opt_run = True
    elif opt == '-s':
        opt_show = True
    elif opt == '-l':
        opt_list = True
    elif opt == '-f':
        opt_fix = True
    elif opt == '-c':
        opt_coverage = True
    elif opt == '-R':
        report_dir = arg
    elif opt == '-S':
        dumps_dir = arg

if opt_run and opt_show:
    usage("Use either -s or -r, not both.")
if args and opt_all:
    usage("Specify either -a or tests, not both.")
if report_dir is not None and not os.path.isdir(report_dir):
    usage("%s is not a directory" % report_dir)

ret = 0
try:
    if args:
        testlist = get_tests(args)
    elif opt_all or opt_list:
        testlist = get_tests(os.listdir(tests_dir))
    else:
        usage("Specify either -a or tests.")

    if opt_run:
        if not os.path.isdir(dumps_dir):
            ERR("Could not find sigrok-dumps repository at %s" % dumps_dir)
            sys.exit(1)
        results, errors = run_tests(testlist, fix=opt_fix)
        ret = 0
        errs, diffs = get_run_tests_error_diff_counts(results)
        if errs:
            ret = 1
        elif diffs:
            ret = 2
    elif opt_show:
        show_tests(testlist)
    elif opt_list:
        list_tests(testlist)
    elif opt_fix:
        run_tests(testlist, fix=True)
    else:
        usage()
except Exception as e:
    print("Error: %s" % str(e))
    if DEBUG:
        raise

sys.exit(ret)