#!/usr/bin/env python3
"""Vega checks: one aup spec, three surfaces.

1. CLI and NUI: examples/todo.aup under random adds, moves, toggles, urgent
   marks and removals prints exactly what a reference Python model of the app
   and of Vega's conventions says (lines for pipes, sentences for speech),
   including failed events on an empty list.
2. TUI: the same runs drawn at several sizes keep the focused row on screen
   with the least scrolling, show the rows around it in order, right-align
   badges by display width (Hangul, CJK and emoji take two cells, combining
   marks none), and evaluate only the cells on screen: a frame costs the
   title, the field, the focus and three cells per visible row, however long
   the list is.
3. Tables: examples/scores.aup aligns its columns by display width and marks
   row tones.
4. Every aup example runs on every surface under random keys without a crash.
5. Stored: surfaces take turns on one store and each continues the list; an
   interactive session's entries are there in the next one.
"""
import argparse
import json
import os
import random
import subprocess
import sys
import tempfile
import unicodedata
from pathlib import Path

HERE = Path(__file__).resolve().parent
ROOT = HERE.parent


def run(*args, stdin='', env=None):
    return subprocess.run([str(a) for a in args], input=stdin, capture_output=True, text=True, timeout=120,
                          env=env)


def width(text):
    total = 0
    for ch in text:
        if unicodedata.combining(ch) or ch in '‍️':
            continue
        total += 2 if unicodedata.east_asian_width(ch) in 'WF' else 1
    return total


def pictures(text):
    """Control characters as Vega shows them."""
    return ''.join(chr(0x2400 + ord(c)) if ord(c) < 0x20 else '␡' if c == '\x7f' else c for c in text)


class Todo:
    """examples/todo.aup and Vega's reading of it."""

    def __init__(self):
        self.tasks, self.at = [], 0

    def event(self, name, text=None):
        """Returns False when the event fails (a missing item)."""
        if name == 'add':
            self.tasks.append({'title': text, 'done': 0, 'urgent': 0})
            self.at = len(self.tasks) - 1
            return True
        last = max(len(self.tasks) - 1, 0)
        if name in ('toggle', 'urgent', 'drop') and not self.tasks:
            return False
        if name == 'up': self.at = max(self.at - 1, 0)
        elif name == 'down': self.at = min(self.at + 1, last)
        elif name == 'toggle': self.tasks[self.at]['done'] = int(not self.tasks[self.at]['done'])
        elif name == 'urgent': self.tasks[self.at]['urgent'] = int(not self.tasks[self.at]['urgent'])
        elif name == 'drop':
            del self.tasks[self.at]
            self.at = min(self.at, max(len(self.tasks) - 1, 0))
        return True

    @staticmethod
    def badge(task):
        return 'done' if task['done'] else 'urgent' if task['urgent'] else ''

    @staticmethod
    def tone(task):
        return 'muted' if task['done'] else 'danger' if task['urgent'] else 'normal'

    def cli(self):
        lines = ['To do', f'left: {len(self.tasks)} tasks', f'tasks_list ({len(self.tasks)})']
        for i, task in enumerate(self.tasks):
            line = ('> ' if i == self.at else '  ') + pictures(task['title'])
            if self.badge(task):
                line += f' [{self.badge(task)}]'
            if self.tone(task) != 'normal':
                line += f' ({self.tone(task)})'
            lines.append(line)
        return lines

    @staticmethod
    def spoken(text):
        text = text.rstrip(''.join(chr(c) for c in range(0x21)))
        return ''.join(' ' if ord(c) < 0x20 else c for c in text)

    def focus(self):
        if not self.tasks:
            return 'tasks_list is empty.'
        task = self.tasks[self.at]
        words = [self.spoken(task['title'])] + ([self.badge(task)] if self.badge(task) else [])
        tone = 'danger, ' if self.tone(task) == 'danger' else ''
        return f'Item {self.at + 1} of {len(self.tasks)}: {tone}' + ', '.join(words) + '.'

    def say(self):
        n = len(self.tasks)
        lines = ['To do.', f'left: {n} tasks.', f'tasks_list, {n} item{"" if n == 1 else "s"}.']
        return lines + ([self.focus()] if n else [])


KEYS = {'up': 'ArrowUp', 'down': 'ArrowDown', 'toggle': 'Space', 'urgent': 'KeyU', 'drop': 'Delete'}
WORDS = ['milk', '우유 사기', 'call 엄마', '日本語', '😀 party', 'café', 'tab\there', 'x' * 60, '', 'a\nb',
         'ok']


def cli_and_say(vega, module, seeds, steps=300):
    compared = failures = 0
    for seed in seeds:
        rng = random.Random(seed)
        model, script, expected_cli, expected_say = Todo(), [], [], []
        for _ in range(steps):
            if rng.random() < 0.25:
                word = rng.choice(WORDS)
                script.append('text ' + (word.encode().hex() or '-'))
                ok, name = model.event('add', word), 'add'
            else:
                name = rng.choice(list(KEYS) + ['drop'])
                script.append(f'key {KEYS[name]}')
                ok = model.event(name)
            expected_say.append(model.focus() if ok else f'Could not {name}.')
            failures += not ok
            if rng.random() < 0.2:
                script.append('show')
                expected_cli += model.cli()
                expected_say += model.say()
        text = '\n'.join(script) + '\n'
        cli = run(vega, 'cli', module, stdin=text)
        assert cli.returncode == 0 and cli.stdout.splitlines() == expected_cli, \
            (seed, [(a, b) for a, b in zip(cli.stdout.splitlines(), expected_cli) if a != b][:3])
        say = run(vega, 'say', module, stdin=text)
        assert say.returncode == 0 and say.stdout.splitlines() == expected_say, \
            (seed, [(a, b) for a, b in zip(say.stdout.splitlines(), expected_say) if a != b][:3])
        compared += len(expected_cli) + len(expected_say)
    return compared, failures


def stored_surfaces(vega, module, work, seeds, steps=240):
    """One store, several surfaces in turn: each run continues the list where
    the last one left it, and prints or says what the model says."""
    compared = 0
    for seed in seeds:
        rng = random.Random(seed + 500)
        model, store = Todo(), work / f'store-{seed}'
        cuts = sorted(rng.sample(range(1, steps), 6))
        for number, (start, end) in enumerate(zip([0] + cuts, cuts + [steps])):
            surface = ['cli', 'say'][number % 2]
            script, expected = [], []
            for _ in range(start, end):
                if rng.random() < 0.3:
                    word = rng.choice(WORDS)
                    script.append('text ' + (word.encode().hex() or '-'))
                    ok, name = model.event('add', word), 'add'
                else:
                    name = rng.choice(list(KEYS) + ['drop'])
                    script.append(f'key {KEYS[name]}')
                    ok = model.event(name)
                if surface == 'say':
                    expected.append(model.focus() if ok else f'Could not {name}.')
            script.append('show')
            expected += model.cli() if surface == 'cli' else model.say()
            out = run(vega, surface, module, '--store', store, stdin='\n'.join(script) + '\n')
            assert out.returncode == 0 and out.stdout.splitlines() == expected, \
                (seed, number, [(a, b) for a, b in zip(out.stdout.splitlines(), expected) if a != b][:3])
            compared += len(expected)
        frame = run(vega, 'tui', module, '--store', store, '--dump', '40x12', stdin='show\n').stdout.splitlines()
        assert frame[2].startswith(f'|tasks_list ({len(model.tasks)})'), frame
    return compared


def frames(output, height):
    lines = output.splitlines()
    for start in range(0, len(lines), height + 1):
        frame, cells = lines[start:start + height], lines[start + height]
        assert len(frame) == height and cells.startswith('cells '), lines[start:start + height + 1]
        yield frame, int(cells.split()[1])


def tui(vega, module, seeds, sizes, steps=300):
    """Each frame against the model: which rows show, which one is focused,
    where badges end, and how many cells were evaluated."""
    checked = 0
    for columns, rows in sizes:
        area = rows - 5  # title, field, list header, key bar, input line
        for seed in seeds:
            rng = random.Random(seed * 7 + columns)
            model, script, states = Todo(), [], []
            for _ in range(steps):
                if rng.random() < 0.3:
                    word = rng.choice(WORDS)
                    script.append('text ' + (word.encode().hex() or '-'))
                    model.event('add', word)
                else:
                    name = rng.choice(list(KEYS))
                    script.append(f'key {KEYS[name]}')
                    model.event(name)
                script.append('show')
                states.append(([dict(t) for t in model.tasks], model.at))
            result = run(vega, 'tui', module, '--dump', f'{columns}x{rows}', stdin='\n'.join(script) + '\n')
            assert result.returncode == 0, result.stderr
            first = 0
            for (frame, cells), (tasks, at) in zip(frames(result.stdout, rows), states):
                n = len(tasks)
                assert frame[0] == '|To do' and frame[2].startswith(f'|tasks_list ({n})'), frame[:3]
                if at < first: first = at
                if at >= first + area: first = at - area + 1
                if first + area > n: first = max(n - area, 0)
                shown = frame[3:3 + area]
                visible = tasks[first:first + area]
                for i, line in enumerate(shown):
                    if i >= len(visible):
                        assert line == '|', (seed, line)
                        continue
                    task, focused = visible[i], first + i == at
                    body = (line[1:].split('\t')[0] + '  ')[:max(2, len(line[1:].split('\t')[0]))]  # trailing spaces are trimmed
                    assert line[0] == ('>' if focused else '|') and body.startswith('> ' if focused else '  '), (seed, i, line)
                    label = pictures(task['title'])
                    badge = Todo.badge(task)
                    if badge:  # the badge ends at the last column
                        assert body.endswith(badge) and width(body) == columns, (seed, body, width(body))
                    if width(label) + 2 + (len(badge) + 2 if badge else 0) <= columns:
                        assert body[2:].startswith(label), (seed, body, label)
                    else:
                        assert '…' in body, (seed, body)
                    tone = Todo.tone(task)
                    assert (line.split('\t')[1] if '\t' in line else 'normal') == tone, (seed, line, tone)
                assert cells == 2 + (2 + 3 * len(visible) if n else 0), (seed, cells, len(visible))
                checked += 1
    # A long list costs what its screen shows: 2,000 tasks, 7 visible rows.
    script = ['text ' + f'task {i}'.encode().hex() for i in range(2000)] + ['key ArrowUp'] * 3 + ['show']
    frame, cells = next(frames(run(vega, 'tui', module, '--dump', '40x12', stdin='\n'.join(script) + '\n').stdout, 12))
    assert cells == 2 + 2 + 3 * 7 and frame[9] == '>> task 1996' and frame[3] == '|  task 1990', (cells, frame)
    return checked


def scores(vega, module):
    joins = ['ann', '범수', 'Zoë']
    script = [f'text {name.encode().hex()}' for name in joins]
    script += ['key ArrowUp', 'key KeyW', 'key KeyW', 'key KeyW', 'key ArrowUp', 'key KeyL', 'show']
    out = run(vega, 'cli', module, stdin='\n'.join(script) + '\n').stdout.splitlines()
    assert out == ['Scores', 'board (3)',
                   '  name  score  rank',
                   '> ann   -1     - (danger)',
                   '  범수  3      gold (good)',
                   '  Zoë   0      -'], out
    tui = run(vega, 'tui', module, '--dump', '30x8', stdin='\n'.join(script) + '\n').stdout.splitlines()
    assert tui[1:5] == ['|board (3)', '|  name  score  rank\tmuted', '>> ann   -1     -\tdanger',
                        '|  범수  3      gold\tgood'], tui
    say = run(vega, 'say', module, stdin='show\n' + '\n'.join(script) + '\n').stdout.splitlines()
    assert 'Item 1 of 3: danger, name ann, score -1, rank -.' in say, say
    return len(out)


def interactive(vega, module, store=None):
    """The terminal surface on a real pseudo-terminal: typed text commits
    with Enter, arrow keys and letters reach the app after Tab, Ctrl-C leaves
    and restores the terminal."""
    import fcntl, pty, select, struct, termios, time
    pid, fd = pty.fork()
    if pid == 0:
        os.execv(str(vega), [str(vega), 'tui', str(module)] + (['--store', str(store)] if store else []))
    fcntl.ioctl(fd, termios.TIOCSWINSZ, struct.pack('HHHH', 10, 40, 0, 0))
    os.kill(pid, 28)  # SIGWINCH: take the size

    def read_for(seconds):
        data, end = b'', time.time() + seconds
        while time.time() < end:
            ready, _, _ = select.select([fd], [], [], 0.05)
            if ready:
                try:
                    data += os.read(fd, 65536)
                except OSError:
                    break
        return data

    screen = read_for(0.3)
    for keys in (b'milk\r', 'b\u00e9ton\r'.encode(), b'\t', b'\x1b[A', b' ', b'u'):
        os.write(fd, keys)
        screen += read_for(0.2)
    os.write(fd, b'\x03')
    screen += read_for(0.3)
    _, status = os.waitpid(pid, 0)
    os.close(fd)
    text = screen.decode(errors='replace')
    assert os.WIFEXITED(status) and os.WEXITSTATUS(status) == 0, status
    assert '\x1b[?1049h' in text and text.rstrip().endswith('\x1b[?1049l'), text[-80:]
    assert 'milk' in text and 'béton' in text and '(2)' in text and 'done' in text, text[-400:]
    if store:  # what was typed is still there in the next session
        again = run(vega, 'cli', module, '--store', store, stdin='show\n').stdout.splitlines()
        assert again == ['To do', 'left: 2 tasks', 'tasks_list (2)', '> milk [done] (muted)', '  béton'], again
    return 1


def robustness(vega, aup, work, rounds):
    """Every aup example, every surface, random keys and text: never a crash."""
    examples = sorted((ROOT.parent / 'aup' / 'examples').glob('*.aup')) + sorted((ROOT / 'examples').glob('*.aup'))
    keys = ['ArrowUp', 'ArrowDown', 'ArrowLeft', 'ArrowRight', 'Space', 'Enter', 'Delete', 'Backspace', 'Home',
            'End', 'KeyD', 'KeyS', 'KeyU', 'KeyW', 'KeyL', 'KeyM']
    env = dict(os.environ, AUP_PATH=str(ROOT / 'lib'))
    runs = 0
    for path in examples:
        module = work / (path.stem + '.pmod')
        built = run(aup, 'build', path, '-o', module, env=env)
        assert built.returncode == 0, (path, built.stderr)
        rng = random.Random(path.stem)
        for _ in range(rounds):
            script = []
            for _ in range(60):
                roll = rng.random()
                if roll < 0.2: script.append('text ' + rng.choice(WORDS).encode().hex())
                elif roll < 0.3: script.append('show')
                elif roll < 0.35: script.append('frame 3')
                elif roll < 0.4: script.append(rng.choice(['type 61', 'enter', 'tab']))
                else: script.append('key ' + rng.choice(keys))
            text = '\n'.join(script) + '\nshow\n'
            for surface in (['cli'], ['say'], ['tui', '--dump', rng.choice(['80x24', '12x5', '1x1', '200x3'])]):
                result = run(vega, surface[0], module, *surface[1:], stdin=text)
                assert result.returncode == 0, (path, surface, result.stderr[-400:])
                runs += 1
    return len(examples), runs


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument('--vega', type=Path, required=True)
    parser.add_argument('--aup', type=Path, required=True)
    parser.add_argument('--seeds', type=int, default=8)
    parser.add_argument('--rounds', type=int, default=3)
    args = parser.parse_args()
    vega, aup = args.vega.resolve(), args.aup.resolve()
    report = {}
    with tempfile.TemporaryDirectory(prefix='vega-check-') as directory:
        work = Path(directory)
        env = dict(os.environ, AUP_PATH=str(ROOT / 'lib'))
        modules = {}
        for name in ('todo', 'scores'):
            modules[name] = work / f'{name}.pmod'
            built = run(aup, 'build', ROOT / 'examples' / f'{name}.aup', '-o', modules[name], env=env)
            assert built.returncode == 0, built.stderr
        report['cli_and_say_lines'], report['failed_events_spoken'] = \
            cli_and_say(vega, modules['todo'], range(args.seeds))
        report['tui_frames'] = tui(vega, modules['todo'], range(args.seeds), [(40, 12), (24, 9), (80, 30), (16, 6)])
        report['table_lines'] = scores(vega, modules['scores'])
        report['interactive_sessions'] = interactive(vega, modules['todo']) + \
            interactive(vega, modules['todo'], work / 'interactive-store')
        report['stored_surface_lines'] = stored_surfaces(vega, modules['todo'], work, range(args.seeds))
        report['examples'], report['robustness_runs'] = robustness(vega, aup, work, args.rounds)
    print(json.dumps(report))


if __name__ == '__main__':
    sys.exit(main())