miniphlow.py

from typing import Callable


class MiniPhlowView:
    name = str
    priority = int

    def render(self):
        print(f"\n--- {self.name} ---")


class MiniPhlowListView(MiniPhlowView):
    items = Callable[[], object]
    show = Callable[[object], str]
    send = Callable[[int], object]

    def render(self):
        super().render()
        items = self.items()
        for i, item in enumerate(items):
            print(f"  {i + 1}. {self.show(item)}")
        return items


class MiniPhlowColumnedListView(MiniPhlowListView):
    items = Callable[[], object]
    columns = dict[str, Callable[[object], str]]
    send = Callable[[int], object]

    def column(self, name, f):
        self.columns[name] = f

    def render(self):
        MiniPhlowView.render(self)
        items = self.items()
        cols = list(self.columns.keys())
        rows = [[f(item) for _, f in self.columns.items()] for item in items]
        widths = [max(len(c), *(len(r[i]) for r in rows)) for i, c in enumerate(cols)]
        header = " | ".join(c.ljust(w) for c, w in zip(cols, widths))
        print(f"  {header}")
        print(f"  {'-+-'.join('-' * w for w in widths)}")
        for i, row in enumerate(rows):
            print(f"  {' | '.join(v.ljust(w) for v, w in zip(row, widths))}")
        return items


def view(func):
    setattr(func, "miniphlow", True)
    return func


def _collect_views(obj):
    views = []
    for name in dir(obj):
        attr = getattr(obj, name)
        if callable(attr) and getattr(attr, "miniphlow", False):
            views.append(attr)
    views.sort(key=lambda v: getattr(v(), "priority", 0))
    return views


def inspect(obj):
    history = []

    while True:
        views = _collect_views(obj)
        if not views:
            print(f"No views for {obj!r}")
            if history:
                obj = history.pop()
                continue
            return

        view_instances = [v() for v in views]
        print(f"\n--- Inspecting: {obj!r} ---")
        print("Views:")
        for i, v in enumerate(view_instances):
            print(f"  [{i + 1}] {v.name}")

        try:
            raw = input("\n> ").strip()
        except (EOFError, KeyboardInterrupt):
            print()
            return

        if raw in ("q", "quit", "exit"):
            return

        if raw in ("b", "back"):
            if history:
                obj = history.pop()
            else:
                print("Nothing to go back to.")
            continue

        parts = raw.split(None, 1)
        if not parts:
            continue

        # select a view
        try:
            view_idx = int(parts[0]) - 1
        except ValueError:
            print("Enter a view number, 'b' to go back, or 'q' to quit.")
            continue

        if view_idx < 0 or view_idx >= len(view_instances):
            print(f"View number out of range (1-{len(view_instances)}).")
            continue

        selected = view_instances[view_idx]
        selected.render()

        while True:
            try:
                raw = input("\nitem> ").strip()
            except (EOFError, KeyboardInterrupt):
                print()
                return

            if raw in ("b", "back", ""):
                break
            if raw in ("q", "quit", "exit"):
                return

            try:
                item_idx = int(raw) - 1
            except ValueError:
                print("Enter an item number or 'b' to go back.")
                continue

            next_obj = selected.send(item_idx)
            history.append(obj)
            obj = next_obj
            break