"""Stable roles for Chrome's otherwise indistinguishable top-level windows."""

from classroom_sway import matches


CHROME_PATTERNS = (
    r"google-chrome",
    r"chrome",
    r"chrome-.*",
    r"google-chrome-.*",
)


def chrome_windows(current):
    """Chrome containers in Sway tree order, without using page titles."""
    return [window for window in current if matches(window, CHROME_PATTERNS)]


class ChromeRoles:
    """Remember the first Chrome container and classify every later one."""

    def __init__(self):
        self.primary = None
        self.secondary = []

    def update(self, current):
        identifiers = [window["id"] for window in chrome_windows(current)]
        previous_primary = self.primary
        previous_secondary = list(self.secondary)

        promoted = None

        if self.primary not in identifiers:
            self.primary = identifiers[0] if identifiers else None

            if self.primary is not None and previous_primary is not None:
                promoted = self.primary

        self.secondary = [
            identifier
            for identifier in previous_secondary
            if identifier in identifiers and identifier != self.primary
        ]

        new_secondary = []

        for identifier in identifiers:
            if identifier == self.primary or identifier in self.secondary:
                continue

            self.secondary.append(identifier)
            new_secondary.append(identifier)

        removed = [
            identifier
            for identifier in previous_secondary
            if identifier not in identifiers
        ]

        return {
            "primary": self.primary,
            "promoted": promoted,
            "new_secondary": new_secondary,
            "removed": removed,
            "active_secondary": self.secondary[-1] if self.secondary else None,
        }