#!/usr/bin/env python3
"""Validate game-start scripts (p3-14) against their schema + semantic rules.

Scripts:   public/resources/start_scripts/*.json  (excluding the schema)
Schema:    public/resources/start_scripts/start_scripts.schema.json
Catalogs:  public/resources/units/*.json (unit ids), vocabulary.json (banner keys)

Mirrors the Rust load-path validator (mc_turn::start_script::validate) and adds
the catalog checks (unit_id exists, banner_key exists) that need the game pack.
Errors name the script id + phase id + op index so a scenario author can jump
straight to the line.

Usage:
    python3 tools/validate-start-scripts.py [--root /path/to/project]

Exit code 0 = all pass, 1 = failures found.
"""

import argparse
import json
import sys
from pathlib import Path

try:
    from jsonschema import Draft202012Validator
    HAS_JSONSCHEMA = True
except ImportError:
    HAS_JSONSCHEMA = False

# Op → the arg keys that reference a declared actor tag / a declared param.
ACTOR_REF_KEYS = {
    "place_spawn_box": ["actor"],
    "roll_actor_directions": ["actor"],
    "step_actors": ["actor"],
    "converge_actors": ["actor", "produce"],
    "set_unit_actions": ["actor"],
    "found_city": ["from"],
}
PARAM_REF_KEYS = {
    "place_spawn_box": ["count_ref", "mode_ref", "radius_ref"],
    "roll_actor_directions": ["mode_ref", "bias_ref"],
    "converge_actors": ["radius_ref", "min_count_ref", "mode_ref", "cap_ref"],
    "found_city": ["mode_ref", "cap_ref"],
}


def load_json(path: Path):
    try:
        return json.loads(path.read_text(encoding="utf-8")), None
    except (OSError, json.JSONDecodeError) as e:
        return None, str(e)


def unit_ids(root: Path) -> set:
    out = set()
    udir = root / "public/resources/units"
    for fp in sorted(udir.glob("*.json")):
        data, _ = load_json(fp)
        if data is None:
            continue
        for entry in data if isinstance(data, list) else [data]:
            if isinstance(entry, dict) and "id" in entry:
                out.add(str(entry["id"]))
    return out


def vocab_keys(root: Path) -> set:
    data, _ = load_json(root / "public/games/age-of-dwarves/vocabulary.json")
    return set(data.keys()) if isinstance(data, dict) else set()


def semantic_errors(script: dict, units: set, vocab: set) -> list:
    sid = script.get("id", "<no-id>")
    errs = []

    def err(loc, msg):
        errs.append(f"start_script '{sid}' {loc}: {msg}")

    actors = {a["tag"]: a for a in script.get("actors", []) if isinstance(a, dict) and "tag" in a}
    params = set(script.get("params", {}).keys())

    # unit_id of each actor must exist in the catalog.
    for tag, a in actors.items():
        uid = a.get("unit_id", "")
        if units and uid not in units:
            err("actors", f"actor '{tag}' unit_id '{uid}' not in unit catalog")

    phases = script.get("phases", [])
    if not any(p.get("kind") == "normal" for p in phases if isinstance(p, dict)):
        err("phases", "no phase of kind 'normal' — the script never hands off to normal play")

    seen_phase = set()
    for p in phases:
        if not isinstance(p, dict):
            continue
        pid = p.get("id", "<no-id>")
        if pid in seen_phase:
            err("phases", f"duplicate phase id '{pid}'")
        seen_phase.add(pid)

        # banner_key must exist in vocabulary.
        bkey = p.get("banner_key")
        if bkey and vocab and bkey not in vocab:
            err(f"phase '{pid}'", f"banner_key '{bkey}' not in vocabulary.json")

        for list_name in ("on_enter", "on_resolve"):
            for i, op in enumerate(p.get(list_name, [])):
                if not isinstance(op, dict):
                    continue
                name = op.get("op", "")
                loc = f"phase '{pid}' {list_name} op[{i}]"
                for k in ACTOR_REF_KEYS.get(name, []):
                    ref = op.get(k)
                    if ref is not None and ref not in actors:
                        err(loc, f"unknown actor '{ref}' in '{k}' (declared: {sorted(actors)})")
                for k in PARAM_REF_KEYS.get(name, []):
                    ref = op.get(k)
                    if ref is not None and ref not in params:
                        err(loc, f"unknown param '{ref}' in '{k}' (declared: {sorted(params)})")
    return errs


def main() -> int:
    ap = argparse.ArgumentParser()
    ap.add_argument("--root", default=str(Path(__file__).resolve().parents[1]))
    args = ap.parse_args()
    root = Path(args.root)

    sdir = root / "public/resources/start_scripts"
    schema_path = sdir / "start_scripts.schema.json"
    if not sdir.is_dir():
        print(f"  no start_scripts dir at {sdir} — nothing to validate")
        return 0

    schema, serr = load_json(schema_path)
    if schema is None:
        print(f"FAIL: cannot load schema {schema_path}: {serr}")
        return 1
    validator = Draft202012Validator(schema) if HAS_JSONSCHEMA else None
    if validator is None:
        print("  WARNING: jsonschema not installed — schema checks skipped (semantic checks still run)")

    units = unit_ids(root)
    vocab = vocab_keys(root)

    passed = 0
    failures = []
    scripts = [p for p in sorted(sdir.glob("*.json")) if p.name != "start_scripts.schema.json"]
    for fp in scripts:
        data, jerr = load_json(fp)
        if data is None:
            failures.append(f"{fp.name}: invalid JSON: {jerr}")
            continue
        file_errs = []
        if validator is not None:
            for e in validator.iter_errors(data):
                loc = "/".join(str(x) for x in e.absolute_path) or "<root>"
                file_errs.append(f"{fp.name} [{loc}]: {e.message}")
        file_errs.extend(semantic_errors(data, units, vocab))
        if file_errs:
            failures.extend(file_errs)
        else:
            passed += 1

    print("=" * 60)
    if failures:
        for f in failures:
            print(f"  FAIL  {f}")
        print("=" * 60)
        print(f"  start-scripts: {passed} passed, {len(failures)} failure(s)")
        return 1
    print(f"  start-scripts: {passed} passed, 0 failures ({len(scripts)} script(s))")
    print("=" * 60)
    return 0


if __name__ == "__main__":
    sys.exit(main())