"""Vuelve a correr los comandos que aparecen en los apuntes y en las diapositivas
y comprueba que el código citado existe de verdad en esta carpeta."""
import os
import pathlib
import platform
import re
import subprocess
import unittest

try:
    import pty
except ImportError:
    pty = None

HERE = pathlib.Path(__file__).parent
ROOT = HERE.parent.parent
NOTES = ROOT / "notes" / "week-01.md"
SLIDES = ROOT / "slides" / "week-01.tex"
# Antes de un bloque cuya salida cambia con el sistema. No se compara.
SYSTEM_DEPENDENT = "<!-- depende del sistema -->"
# Antes de un informe del compilador o de un sanitizer. Puede omitir líneas, pero no
# cambiarlas ni reordenarlas. Las direcciones y los números de proceso no se comparan.
REPORT = "<!-- informe recortado -->"
# Los informes se capturaron en esta arquitectura: en otra cambian líneas de las bibliotecas.
REPORT_MACHINE = "aarch64"


def normalize(text):
    # Según el idioma del entorno, g++ usa comillas tipográficas o rectas.
    return text.replace("‘", "'").replace("’", "'")


def run_shell(command):
    done = subprocess.run(
        ["bash", "-c", command], cwd=HERE, text=True, encoding="utf-8",
        stdin=subprocess.DEVNULL, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, timeout=120,
    )
    return normalize(done.stdout)


def run_in_terminal(command):
    """Corre el comando en una terminal de verdad: así se intercala la salida del programa
    con el informe, igual que cuando ustedes lo corren."""
    master, slave = pty.openpty()
    process = subprocess.Popen(
        ["bash", "-c", command], cwd=HERE, stdin=subprocess.DEVNULL, stdout=slave, stderr=slave,
    )
    os.close(slave)
    data = b""
    while True:
        try:
            chunk = os.read(master, 4096)
        except OSError:
            break
        if not chunk:
            break
        data += chunk
    os.close(master)
    process.wait(timeout=120)
    text = data.decode("utf-8", errors="replace").replace("\r", "")
    return normalize(re.sub(r"\x1b\[[0-9;]*[mK]", "", text))


def clean_lines(text):
    return [line.rstrip() for line in text.splitlines()]


def stable(line):
    """Quita de una línea de informe lo que cambia en cada corrida."""
    line = re.sub(r"0x[0-9a-f]+", "ADDR", line.strip())
    return re.sub(r"==\d+==", "==N==", line)


def split_commands(lines):
    """Parte un bloque de terminal en pares (comando, líneas de salida)."""
    pairs = []
    for line in lines:
        if line.startswith("$ "):
            pairs.append((line[2:], []))
        elif pairs:
            pairs[-1][1].append(normalize(line.rstrip()))
    return pairs


def note_blocks(language):
    """Devuelve (líneas, marca) de cada bloque de los apuntes."""
    blocks, current, mark, previous = [], None, "", ""
    for raw in NOTES.read_text(encoding="utf-8").splitlines():
        line = re.sub(r"^> ?", "", raw)
        if current is None:
            if line.strip() == "```" + language:
                current, mark = [], previous.strip()
            elif line.strip():
                previous = line
        elif line.strip() == "```":
            blocks.append((current, mark))
            current = None
        else:
            current.append(line)
    return blocks


def slide_blocks(environments):
    text = SLIDES.read_text(encoding="utf-8")
    pattern = r"\\begin\{(?:%s)\}[^\n]*\n(.*?)\\end\{(?:%s)\}" % (environments, environments)
    return [match.group(1).splitlines() for match in re.finditer(pattern, text, re.S)]


def known_code_lines():
    lines = set()
    sources = []
    for folder in (HERE, HERE / "errors", HERE / "tally_c", HERE / "lab", HERE / "lab" / "c", HERE / "lab" / "tests"):
        for pattern in ("*.cpp", "*.h", "*.c"):
            sources += folder.glob(pattern)
    for source in sources:
        lines.update(line.strip() for line in source.read_text(encoding="utf-8").splitlines())
    return lines


class ReportCheck(unittest.TestCase):
    def assert_in_order(self, command, expected, actual):
        """Las líneas esperadas aparecen en la salida real, en orden. '...' marca un recorte."""
        wanted = [stable(line) for line in expected if line.strip() and line.strip() != "..."]
        real = [stable(line) for line in actual]
        position = 0
        for line in wanted:
            with self.subTest(command=command, line=line):
                found = [i for i in range(position, len(real)) if real[i] == line]
                self.assertTrue(found, f"no aparece en la salida real: {line}")
                if found:
                    position = found[0] + 1


class NotesAreTrue(ReportCheck):
    @unittest.skipUnless(NOTES.exists(), "faltan los apuntes")
    def test_terminal_blocks_in_notes(self):
        checked = 0
        for lines, mark in note_blocks("text"):
            if not lines or not lines[0].startswith("$ ") or mark == REPORT:
                continue
            for command, expected in split_commands(lines):
                actual = clean_lines(run_shell(command))
                checked += 1
                if mark != SYSTEM_DEPENDENT:
                    with self.subTest(command=command):
                        self.assertEqual(actual, expected)
        self.assertGreater(checked, 15)

    @unittest.skipUnless(NOTES.exists(), "faltan los apuntes")
    @unittest.skipUnless(pty and platform.machine() == REPORT_MACHINE, "los informes son de aarch64")
    def test_reports_in_notes(self):
        checked = 0
        for lines, mark in note_blocks("text"):
            if mark != REPORT:
                continue
            for command, expected in split_commands(lines):
                actual = clean_lines(run_in_terminal(command))
                self.assert_in_order(command, expected, actual)
                checked += 1
        self.assertGreater(checked, 8)

    @unittest.skipUnless(NOTES.exists(), "faltan los apuntes")
    def test_code_blocks_in_notes_exist(self):
        known = known_code_lines()
        for language in ("c", "cpp"):
            for lines, _ in note_blocks(language):
                for line in lines:
                    if line.strip() and line.strip() != "...":
                        with self.subTest(line=line):
                            self.assertIn(line.strip(), known)


class SlidesAreTrue(ReportCheck):
    @unittest.skipUnless(SLIDES.exists(), "faltan las diapositivas")
    def test_program_output_in_slides(self):
        for block in slide_blocks("terminal|salida"):
            for command, expected in split_commands(block):
                self.assert_in_order(command, expected, clean_lines(run_shell(command)))

    # Algunos informes usan programas que compiló la prueba de los apuntes, que corre antes.
    @unittest.skipUnless(SLIDES.exists(), "faltan las diapositivas")
    @unittest.skipUnless(pty and platform.machine() == REPORT_MACHINE, "los informes son de aarch64")
    def test_reports_in_slides(self):
        for block in slide_blocks("informe"):
            for command, expected in split_commands(block):
                self.assert_in_order(command, expected, clean_lines(run_in_terminal(command)))

    @unittest.skipUnless(SLIDES.exists(), "faltan las diapositivas")
    def test_code_blocks_in_slides_exist(self):
        known = known_code_lines()
        for block in slide_blocks("codigo|codigochico|codigomini"):
            for line in block:
                if line.strip() and line.strip() != "...":
                    with self.subTest(line=line):
                        self.assertIn(line.strip(), known)


if __name__ == "__main__":
    unittest.main()