#!/usr/bin/env python3
"""
spr - Soleprint component manager

Manages distributable components from the spr repo into target folders.
Runs from spr/. Consuming projects have no awareness of spr — they just
commit whatever lands in the target folder.

Usage:
    python ctrl/spr.py list
    python ctrl/spr.py sync soleprint-ui ~/wdir/unt/ui/framework
    python ctrl/spr.py watch soleprint-ui ~/wdir/unt/ui/framework   # ctrl+c to stop
    python ctrl/spr.py publish soleprint-ui ~/wdir/mpr/ui/framework
    python ctrl/spr.py diff soleprint-ui ~/wdir/mpr/ui/framework
"""

import argparse
import json
import logging
import shutil
import subprocess
import sys
import time
from datetime import datetime, timezone
from pathlib import Path

log = logging.getLogger("spr")

SPR_HOME = Path(__file__).resolve().parent.parent
REGISTRY_PATH = SPR_HOME / "registry.json"

EXCLUDE = {
    "node_modules",
    "__pycache__",
    ".venv",
    "dist",
    ".git",
    "*.egg-info",
    ".spr",
    "pnpm-lock.yaml",
}


def load_registry():
    if not REGISTRY_PATH.exists():
        log.error("registry not found: %s", REGISTRY_PATH)
        sys.exit(1)
    return json.loads(REGISTRY_PATH.read_text())


def resolve_component(registry, name):
    if name not in registry:
        log.error("unknown component: %s", name)
        log.info("available: %s", ", ".join(registry.keys()))
        sys.exit(1)

    entry = registry[name]
    source = SPR_HOME / entry["path"]
    if not source.is_dir():
        log.error("source not found: %s", source)
        sys.exit(1)

    return entry["type"], source


def get_version(comp_type, source):
    try:
        if comp_type == "npm":
            pkg = json.loads((source / "package.json").read_text())
            return pkg.get("version", "?")
        elif comp_type == "pip":
            for line in (source / "pyproject.toml").read_text().splitlines():
                if line.strip().startswith("version"):
                    return line.split('"')[1]
    except FileNotFoundError:
        pass
    return "?"


def get_sha():
    try:
        result = subprocess.run(
            ["git", "rev-parse", "--short", "HEAD"],
            cwd=SPR_HOME,
            capture_output=True,
            text=True,
        )
        return result.stdout.strip() if result.returncode == 0 else "unknown"
    except FileNotFoundError:
        return "unknown"


def should_exclude(path, base):
    """Check if a path should be excluded from sync."""
    rel = path.relative_to(base)
    for part in rel.parts:
        if part in EXCLUDE:
            return True
        for pattern in EXCLUDE:
            if "*" in pattern and part.endswith(pattern.replace("*", "")):
                return True
    return False


def copy_tree(src, dst):
    """Copy src to dst, excluding build artifacts. Returns count of files copied."""
    count = 0
    dst.mkdir(parents=True, exist_ok=True)

    for item in src.iterdir():
        if should_exclude(item, src.parent):
            continue

        target = dst / item.name
        if item.is_dir():
            count += copy_tree(item, target)
        else:
            target.parent.mkdir(parents=True, exist_ok=True)
            shutil.copy2(item, target)
            count += 1

    return count


def sync_tree(src, dst):
    """Bidirectional sync — newest file wins. Returns (fwd, rev) counts."""
    fwd = _sync_one_way(src, dst)
    rev = _sync_one_way(dst, src)
    return fwd, rev


def _sync_one_way(src, dst):
    """Copy files from src to dst only if src is newer."""
    count = 0
    if not src.is_dir():
        return count

    dst.mkdir(parents=True, exist_ok=True)

    for item in src.iterdir():
        if should_exclude(item, src.parent):
            continue

        target = dst / item.name
        if item.is_dir():
            count += _sync_one_way(item, target)
        else:
            if not target.exists() or item.stat().st_mtime > target.stat().st_mtime:
                target.parent.mkdir(parents=True, exist_ok=True)
                shutil.copy2(item, target)
                count += 1

    # Remove files in dst that don't exist in src
    if dst.is_dir():
        for item in dst.iterdir():
            if should_exclude(item, dst.parent):
                continue
            counterpart = src / item.name
            if not counterpart.exists():
                if item.is_dir():
                    shutil.rmtree(item)
                else:
                    item.unlink()
                count += 1

    return count


def write_stamp(dest, name, comp_type, source, mode):
    version = get_version(comp_type, source)
    sha = get_sha()
    stamp = dest / ".spr"
    stamp.write_text(
        f"name={name}\n"
        f"version={version}\n"
        f"type={comp_type}\n"
        f"sha={sha}\n"
        f"mode={mode}\n"
        f"updated={datetime.now(timezone.utc).strftime('%Y-%m-%dT%H:%M:%SZ')}\n"
        f"source={source}\n"
    )


# ── commands ─────────────────────────────────────────────────


def cmd_list(args):
    registry = load_registry()
    log.info("Components (%s):\n", REGISTRY_PATH)
    for name, entry in registry.items():
        comp_type = entry["type"]
        source = SPR_HOME / entry["path"]
        version = get_version(comp_type, source)
        log.info("  %s %s v%-10s %s", f"{name:<25}", f"{comp_type:<5}", version, entry["path"])


def cmd_publish(args):
    registry = load_registry()
    comp_type, source = resolve_component(registry, args.component)
    dest = Path(args.dest).resolve()

    if dest.exists():
        shutil.rmtree(dest)

    count = copy_tree(source, dest)
    write_stamp(dest, args.component, comp_type, source, "published")

    version = get_version(comp_type, source)
    sha = get_sha()
    log.info("%s v%s (%s) -> %s (%d files)", args.component, version, sha, dest, count)


def cmd_sync(args):
    registry = load_registry()
    comp_type, source = resolve_component(registry, args.component)
    dest = Path(args.dest).resolve()
    dest.mkdir(parents=True, exist_ok=True)

    fwd, rev = sync_tree(source, dest)
    write_stamp(dest, args.component, comp_type, source, "synced")

    log.info("%s synced (%d fwd, %d rev)", args.component, fwd, rev)


def cmd_watch(args):
    registry = load_registry()
    comp_type, source = resolve_component(registry, args.component)
    dest = Path(args.dest).resolve()
    dest.mkdir(parents=True, exist_ok=True)
    interval = args.interval

    # Initial sync
    fwd, rev = sync_tree(source, dest)
    write_stamp(dest, args.component, comp_type, source, "watching")
    log.info("%s initial sync (%d fwd, %d rev)", args.component, fwd, rev)
    log.info("  source: %s", source)
    log.info("  dest:   %s", dest)
    log.info("  watching every %ds — ctrl+c to stop", interval)

    try:
        while True:
            time.sleep(interval)
            fwd, rev = sync_tree(source, dest)
            if fwd or rev:
                log.info("synced (%d fwd, %d rev)", fwd, rev)
    except KeyboardInterrupt:
        # Final sync
        fwd, rev = sync_tree(source, dest)
        if fwd or rev:
            log.info("final sync (%d fwd, %d rev)", fwd, rev)
        log.info("stopped")


def cmd_diff(args):
    registry = load_registry()
    _, source = resolve_component(registry, args.component)
    dest = Path(args.dest).resolve()

    if not dest.exists():
        log.error("%s not found at %s", args.component, dest)
        sys.exit(1)

    result = subprocess.run(
        [
            "diff",
            "-rq",
            "--exclude=node_modules",
            "--exclude=__pycache__",
            "--exclude=.venv",
            "--exclude=dist",
            "--exclude=*.egg-info",
            "--exclude=.git",
            "--exclude=.spr",
            "--exclude=pnpm-lock.yaml",
            str(source),
            str(dest),
        ],
        capture_output=True,
        text=True,
    )
    if result.stdout:
        log.info("\n%s", result.stdout.rstrip())
    else:
        log.info("%s is in sync", args.component)


# ── main ─────────────────────────────────────────────────────


def main():
    logging.basicConfig(
        level=logging.DEBUG if "--debug" in sys.argv else logging.INFO,
        format="%(levelname)s %(message)s" if "--debug" in sys.argv else ":: %(message)s",
    )
    sys.argv = [a for a in sys.argv if a != "--debug"]

    parser = argparse.ArgumentParser(
        prog="spr",
        description="Soleprint component manager",
    )
    sub = parser.add_subparsers(dest="command")

    sub.add_parser("list", help="show available components")

    for cmd in ("publish", "sync", "diff"):
        p = sub.add_parser(cmd)
        p.add_argument("component", help="component name")
        p.add_argument("dest", help="target folder path")

    p = sub.add_parser("watch", help="continuous two-way sync (foreground, ctrl+c to stop)")
    p.add_argument("component", help="component name")
    p.add_argument("dest", help="target folder path")
    p.add_argument("-i", "--interval", type=int, default=2, help="poll interval in seconds (default: 2)")

    args = parser.parse_args()
    if not args.command:
        parser.print_help()
        sys.exit(0)

    {
        "list": cmd_list,
        "publish": cmd_publish,
        "sync": cmd_sync,
        "watch": cmd_watch,
        "diff": cmd_diff,
    }[args.command](args)


if __name__ == "__main__":
    main()