"""test_reports_query.py - Unit tests for query report"""
# Copyright © 2021  Brett Smith
# License: AGPLv3-or-later WITH Beancount-Plugin-Additional-Permission-1.0
#
# Full copyright and licensing details can be found at toplevel file
# LICENSE.txt in the repository.

import argparse
import collections
import copy
import csv
import datetime
import io
import itertools
import re

import pytest

from . import testutil

from conservancy_beancount.books import FiscalYear
from conservancy_beancount.reports import query as qmod

from decimal import Decimal

class MockRewriteRuleset:
    def __init__(self, multiplier=2):
        self.multiplier = multiplier

    def rewrite(self, posts):
        for post in posts:
            number, currency = post.units
            number *= self.multiplier
            yield post._replace(units=testutil.Amount(number, currency))


@pytest.fixture(scope='module')
def fy():
    return FiscalYear(3, 1)

def pipe_main(arglist, config):
    stdout = io.StringIO()
    stderr = io.StringIO()
    returncode = qmod.main(arglist, stdout, stderr, config)
    return returncode, stdout, stderr

def query_args(query=None, start_date=None, stop_date=None, join='AND'):
    join = qmod.JoinOperator[join]
    return argparse.Namespace(**locals())

def test_books_loader_empty():
    result = qmod.BooksLoader(None)()
    assert not result.entries
    assert len(result.errors) == 1

def test_books_loader_plain():
    books_path = testutil.test_path(f'books/books/2018.beancount')
    loader = testutil.TestBooksLoader(books_path)
    result = qmod.BooksLoader(loader)()
    assert not result.errors
    assert result.entries
    min_date = datetime.date(2018, 3, 1)
    assert all(ent.date >= min_date for ent in result.entries)

def test_books_loader_rewrites():
    rewrites = [MockRewriteRuleset()]
    books_path = testutil.test_path(f'books/books/2018.beancount')
    loader = testutil.TestBooksLoader(books_path)
    result = qmod.BooksLoader(loader, None, None, rewrites)()
    assert not result.errors
    assert result.entries
    numbers = frozenset(
        abs(post.units.number)
        for entry in result.entries
        for post in getattr(entry, 'postings', ())
    )
    assert numbers
    assert all(abs(number) >= 40 for number in numbers)

@pytest.mark.parametrize('file_s', [None, '', ' \n \n\n'])
def test_build_query_empty(fy, file_s):
    args = query_args()
    if file_s is None:
        query = qmod.build_query(args, fy)
    else:
        with io.StringIO(file_s) as qfile:
            query = qmod.build_query(args, fy, qfile)
    assert query is None

@pytest.mark.parametrize('query_str', [
    'SELECT * WHERE date >= 2018-03-01',
    'select *',
    'JOURNAL "Income:Donations"',
    'journal',
    'BALANCES FROM year=2018',
    'balances',
])
def test_build_query_in_arglist(fy, query_str):
    args = query_args(query_str.split(), testutil.PAST_DATE, testutil.FUTURE_DATE)
    assert qmod.build_query(args, fy) == query_str

@pytest.mark.parametrize('count,join_op', enumerate(qmod.JoinOperator, 1))
def test_build_query_where_arglist_conditions(fy, count, join_op):
    conds = ['account ~ "^Income:"', 'year >= 2018'][:count]
    args = query_args(conds, join=join_op.name)
    query = qmod.build_query(args, fy)
    assert query.startswith('SELECT ')
    cond_index = query.index(' WHERE ') + 7
    assert query[cond_index:] == '({})'.format(join_op.join(conds))

@pytest.mark.parametrize('argname,date_arg', itertools.product(
    ['start_date', 'stop_date'],
    [testutil.FY_START_DATE, testutil.FY_START_DATE.year],
))
def test_build_query_one_date_arg(fy, argname, date_arg):
    query_kwargs = {
        argname: date_arg,
        'query': ['flag = "*"', 'flag = "!"'],
        'join': 'OR',
    }
    args = query_args(**query_kwargs)
    query = qmod.build_query(args, fy)
    assert query.startswith('SELECT ')
    cond_index = query.index(' WHERE ') + 7
    if argname == 'start_date':
        expect_op = '>='
        year_to_date = fy.first_date
    else:
        expect_op = '<'
        year_to_date = fy.next_fy_date
    if not isinstance(date_arg, datetime.date):
        date_arg = year_to_date(date_arg)
    assert query[cond_index:] == '({}) AND date {} {}'.format(
        ' OR '.join(query_kwargs['query']), expect_op, date_arg.isoformat(),
    )

@pytest.mark.parametrize('start_date,stop_date', itertools.product(
    [testutil.PAST_DATE, testutil.PAST_DATE.year],
    [testutil.FUTURE_DATE, testutil.FUTURE_DATE.year],
))
def test_build_query_two_date_args(fy, start_date, stop_date):
    args = query_args(['account ~ "^Equity:"'], start_date, stop_date, 'AND')
    query = qmod.build_query(args, fy)
    assert query.startswith('SELECT ')
    cond_index = query.index(' WHERE ') + 7
    if isinstance(start_date, int):
        start_date = fy.first_date(start_date)
    if isinstance(stop_date, int):
        stop_date = fy.next_fy_date(stop_date)
    assert query[cond_index:] == '({}) AND date >= {} AND date < {}'.format(
        args.query[0], start_date.isoformat(), stop_date.isoformat(),
    )

def test_build_query_plain_from_file(fy):
    with io.StringIO("SELECT *\n WHERE account ~ '^Assets:';\n") as qfile:
        query = qmod.build_query(query_args(), fy, qfile)
    assert re.fullmatch(r"SELECT \*\s+WHERE account ~ '\^Assets:';\s*", query)

def test_build_query_from_file_where_clauses(fy):
    conds = ["account ~ '^Income:'", "account ~ '^Expenses:'"]
    args = query_args(None, testutil.PAST_DATE, testutil.FUTURE_DATE, 'OR')
    with io.StringIO(''.join(f'{s}\n' for s in conds)) as qfile:
        query = qmod.build_query(args, fy, qfile)
    assert query.startswith('SELECT ')
    cond_index = query.index(' WHERE ') + 7
    assert query[cond_index:] == '({}) AND date >= {} AND date < {}'.format(
        ' OR '.join(conds),
        testutil.PAST_DATE.isoformat(),
        testutil.FUTURE_DATE.isoformat(),
    )

@pytest.mark.parametrize('arglist,fy', testutil.combine_values(
    [['--report-type', 'text'], ['--format=text'], ['-f', 'txt']],
    range(2018, 2021),
))
def test_text_query(arglist, fy):
    books_path = testutil.test_path(f'books/books/{fy}.beancount')
    config = testutil.TestConfig(books_path=books_path)
    arglist += ['select', 'date,', 'narration,', 'account,', 'position']
    returncode, stdout, stderr = pipe_main(arglist, config)
    assert returncode == 0
    stdout.seek(0)
    lines = iter(stdout)
    next(lines); next(lines)  # Skip header
    for count, line in enumerate(lines, 1):
        assert re.match(rf'^{fy}-\d\d-\d\d\s+{fy} donation\b', line)
    assert count >= 2

@pytest.mark.parametrize('arglist,fy', testutil.combine_values(
    [['--format=csv'], ['-f', 'csv'], ['-t', 'csv']],
    range(2018, 2021),
))
def test_csv_query(arglist, fy):
    books_path = testutil.test_path(f'books/books/{fy}.beancount')
    config = testutil.TestConfig(books_path=books_path)
    arglist += ['select', 'date,', 'narration,', 'account,', 'position']
    returncode, stdout, stderr = pipe_main(arglist, config)
    assert returncode == 0
    stdout.seek(0)
    for count, row in enumerate(csv.DictReader(stdout), 1):
        assert re.fullmatch(rf'{fy}-\d\d-\d\d', row['date'])
        assert row['narration'] == f'{fy} donation'
    assert count >= 2

@pytest.mark.parametrize('end_index', range(3))
def test_rewrite_query(end_index):
    books_path = testutil.test_path(f'books/books/2018.beancount')
    config = testutil.TestConfig(books_path=books_path)
    accounts = ['Assets', 'Income']
    expected = frozenset(accounts[:end_index])
    rewrite_paths = [
        testutil.test_path(f'userconfig/Rewrite{s}.yml')
        for s in expected
    ]
    arglist = [f'--rewrite-rules={path}' for path in rewrite_paths]
    arglist.append('--format=txt')
    arglist.append('select any_meta("root") as root')
    returncode, stdout, stderr = pipe_main(arglist, config)
    assert returncode == 0
    stdout.seek(0)
    actual = frozenset(line.rstrip('\n') for line in stdout)
    assert expected.issubset(actual)
    assert frozenset(accounts).difference(expected).isdisjoint(actual)