#!/usr/bin/env python3
"""Small Ralph/prd.json progress dashboard for local project tasks.

Usage:
  python scripts/ralph_progress.py
  python scripts/ralph_progress.py .scratch/distributed-inference-network/prd.json
"""

from __future__ import annotations

import json
import shutil
import sys
from pathlib import Path
from textwrap import shorten


REPO_ROOT = Path(__file__).resolve().parents[1]
DEFAULT_PRD = REPO_ROOT / ".scratch/distributed-inference-network/prd.json"
USAGE = "Usage: ralph_progress.py [path/to/prd.json]"


def _status_symbol(passes: bool, blocked: bool) -> str:
    if passes:
        return "✓"
    if blocked:
        return "•"
    return "→"


def _bar(done: int, total: int, width: int = 28) -> str:
    if total <= 0:
        return "[" + "-" * width + "]"
    filled = round(width * done / total)
    return "[" + "#" * filled + "-" * (width - filled) + "]"


def _load_prd(path: Path) -> dict:
    try:
        return json.loads(path.read_text(encoding="utf-8"))
    except FileNotFoundError:
        raise SystemExit(f"PRD not found: {path}")
    except json.JSONDecodeError as exc:
        raise SystemExit(f"Invalid JSON in {path}: {exc}")


def _deps_done(story: dict, story_by_id: dict[str, dict]) -> bool:
    return all(story_by_id.get(dep, {}).get("passes") for dep in story.get("dependsOn", []))


def main(argv: list[str]) -> int:
    if any(arg in {"-h", "--help"} for arg in argv[1:]):
        print(USAGE)
        return 0
    if len(argv) > 2:
        raise SystemExit(USAGE)
    path = Path(argv[1]) if len(argv) == 2 else DEFAULT_PRD
    data = _load_prd(path)
    stories = data.get("userStories", [])
    story_by_id = {story.get("id", ""): story for story in stories}
    total = len(stories)
    done = sum(1 for story in stories if story.get("passes"))
    ready = [story for story in stories if not story.get("passes") and _deps_done(story, story_by_id)]
    blocked = [story for story in stories if not story.get("passes") and not _deps_done(story, story_by_id)]

    columns = shutil.get_terminal_size((100, 24)).columns
    title = data.get("name", path.stem)
    percent = int(done * 100 / total) if total else 0

    print(f"Ralph progress: {title}")
    print(f"PRD: {path}")
    print(f"{_bar(done, total)} {done}/{total} complete ({percent}%)")
    print(f"Ready: {len(ready)}   Blocked: {len(blocked)}")
    print()

    for story in stories:
        story_id = story.get("id", "?")
        title = story.get("title", "(untitled)")
        passes = bool(story.get("passes"))
        deps_ok = _deps_done(story, story_by_id)
        symbol = _status_symbol(passes, blocked=not deps_ok)
        dep_text = ""
        if not passes and story.get("dependsOn"):
            unmet = [dep for dep in story["dependsOn"] if not story_by_id.get(dep, {}).get("passes")]
            if unmet:
                dep_text = f"  waits: {', '.join(unmet)}"
        line = f"{symbol} {story_id:<6} {title}{dep_text}"
        print(shorten(line, width=columns, placeholder="…"))

    if ready:
        next_story = sorted(ready, key=lambda item: item.get("priority", 9999))[0]
        print()
        print(f"Next ready task: {next_story.get('id')} — {next_story.get('title')}")
        notes = next_story.get("notes")
        if notes:
            print(notes)
    return 0


if __name__ == "__main__":
    raise SystemExit(main(sys.argv))