#!/usr/bin/env python3
"""Compare every node's declared outputSchema against what it actually returns.

Why this exists: an outputSchema is what tells a workflow author, and the
WebUI's field-path picker, where a value lives in a node's output. It drifts
silently - a node's execute() changes and nobody remembers to update the
schema next to it - and a wrong schema is worse than no schema, because it
looks authoritative while pointing at the wrong path.

This reuses the existing tests/nodes/*.json fixtures and the same execution
mechanism as scripts/verify-node.py (create a throwaway workflow, run it,
read back each node's real output from the execution record) rather than
adding a second corpus to maintain. For every node type that completed at
least once across the fixtures, it unions the top-level keys of every
observed output and checks each one is covered by that node type's declared
outputSchema - as a plain property, a patternProperties match (for
dynamic-named branches such as switch's case0/case1), or additionalProperties
being explicitly true (for nodes whose real shape is inherently dynamic, such
as set-fields and workflow-input).

A key the schema does not cover is reported as drift. A key the schema
declares but no fixture ever produced is not reported - fixtures are a
sample, not exhaustive, and many declared keys are genuinely conditional
(an error field that only appears on failure, for instance).

Usage:
    ./scripts/check-output-schema-drift.py            # all fixtures
    ./scripts/check-output-schema-drift.py case1 case2 # only these fixtures (by file stem)

Exit 0 if every observed key is covered, 1 if any node type shows drift.
Requires the webserver and a runner to be up (same as run-node-tests.sh).
"""
import importlib.util
import json
import subprocess
import sys
import time
from pathlib import Path

ROOT = Path(__file__).resolve().parent.parent
TESTS_DIR = ROOT / "tests" / "nodes"


def load_verify_node():
    spec = importlib.util.spec_from_file_location("verify_node", ROOT / "scripts" / "verify-node.py")
    mod = importlib.util.module_from_spec(spec)
    spec.loader.exec_module(mod)
    return mod


def load_schemas():
    proc = subprocess.run(
        ["node", str(ROOT / "scripts" / "extract-output-schemas.js")],
        capture_output=True, text=True, cwd=ROOT,
    )
    if proc.returncode != 0:
        raise SystemExit("extract-output-schemas.js failed:\n" + proc.stderr)
    if proc.stderr:
        sys.stderr.write(proc.stderr)
    return json.loads(proc.stdout)


# Added by the engine itself to any node's stored result, regardless of node
# type - not something an individual node's own outputSchema should have to
# declare. See workflow_engine.cpp: applyNodeMarkers (_appliedConfig,
# _ignoredConfigKeys, written whenever a Configurator feeds the node) and the
# loop body runner (_executedInLoop, written to every node that ran inside a
# Loop). A node-specific drift is one the node's own execute() introduced;
# these are not that.
ENGINE_ADDED_KEYS = {"_executedInLoop", "_appliedConfig", "_ignoredConfigKeys"}


def key_covered(key, schema):
    if key in ENGINE_ADDED_KEYS:
        return True
    if key in schema["properties"]:
        return True
    for pattern in schema["patternProperties"]:
        if __import__("re").match(pattern, key):
            return True
    return schema["additionalProperties"] is True


def run_case(vn, case_path, token):
    """Runs one fixture like verify-node.py does, but only to observe outputs -
    assertions in the fixture are ignored here, drift is a separate concern
    from behavioural correctness, and a fixture that intentionally exercises a
    failure path (errorContains, expectMissing) is exactly the kind of case
    that would otherwise make this look like a runner problem."""
    case = json.loads(case_path.read_text())

    if "http" in case:
        # These assert on the raw HTTP response, but the workflow underneath
        # still runs ordinary nodes - run it as a click/manual case instead so
        # the nodes still execute and still get observed.
        pass

    unmet = vn.precondition_unmet(case)
    if unmet:
        return None, f"skipped: {unmet}"

    node_types = {n["id"]: n["type"] for n in case.get("nodes", [])}

    helper_ids = []
    for helper in case.get("helpers", []):
        made = vn.call("POST", "/workflows", token, {
            "name": helper["name"],
            "nodes": helper["nodes"],
            "connections": helper.get("connections", []),
        })
        helper_id = made.get("id") or made.get("_id")
        if not helper_id:
            return None, "no id for helper"
        helper_ids.append(helper_id)
        if helper.get("active", True):
            vn.call("POST", f"/workflows/{helper_id}/activate", token, {})
        case = json.loads(json.dumps(case).replace("{{helper:" + helper["key"] + "}}", helper_id))

    created = vn.call("POST", "/workflows", token, {
        "name": case["name"],
        "nodes": case["nodes"],
        "connections": case["connections"],
        "settings": case.get("settings", {}),
    })
    workflow_id = created.get("id") or created.get("_id")
    if not workflow_id:
        return None, "no workflow id"

    observed = {}
    try:
        if "http" in case:
            vn.call("POST", f"/workflows/{workflow_id}/activate", token, {})
            try:
                vn.run_http_case(case, token, workflow_id)
            except SystemExit:
                pass
            # The webhook call already ran the workflow; find its execution.
            execs = vn.call("GET", f"/executions?pageSize=1&workflowId={workflow_id}", token)
            executions = execs.get("executions", [])
            if not executions:
                return {}, None
            execution_id = executions[0]["_id"]
        else:
            started = vn.call("POST", f"/workflows/{workflow_id}/execute", token, {})
            execution_id = started["executionId"]
            if "resume" in case:
                try:
                    vn.run_resume_case(case, token, execution_id)
                except SystemExit as e:
                    return None, f"resume setup failed: {e}"

        execution = None
        for _ in range(60):
            time.sleep(0.5)
            execution = vn.call("GET", f"/executions/{execution_id}", token)
            if execution.get("status") in ("completed", "failed", "cancelled", "waiting"):
                break
        else:
            return None, "execution did not finish"

        for node_exec in execution.get("nodeExecutions", []):
            if node_exec.get("status") != "completed":
                continue
            node_type = node_types.get(node_exec.get("nodeId"))
            if not node_type:
                continue
            output = node_exec.get("output")
            if not isinstance(output, dict):
                continue
            observed.setdefault(node_type, set()).update(output.keys())

        return observed, None
    finally:
        vn.call("DELETE", f"/workflows/{workflow_id}", token)
        for helper_id in helper_ids:
            vn.call("DELETE", f"/workflows/{helper_id}", token)


def main():
    vn = load_verify_node()
    schemas = load_schemas()

    wanted = sys.argv[1:]
    cases = sorted(TESTS_DIR.glob("*.json"))
    if wanted:
        cases = [c for c in cases if c.stem in wanted]
        if not cases:
            raise SystemExit(f"no fixtures matched {wanted}")

    token = vn.login()
    vn.call("POST", "/nodes/migrate", token, {"nodesPath": "./nodes"})

    observed_by_type = {}
    skipped = []
    errors = []

    for case_path in cases:
        try:
            observed, note = run_case(vn, case_path, token)
        except Exception as exc:  # a broken fixture should not abort the whole scan
            errors.append(f"{case_path.stem}: {exc}")
            continue
        if note and observed is None:
            skipped.append(f"{case_path.stem}: {note}")
            continue
        for node_type, keys in (observed or {}).items():
            observed_by_type.setdefault(node_type, set()).update(keys)

    drift = {}
    for node_type, keys in sorted(observed_by_type.items()):
        schema = schemas.get(node_type)
        if schema is None:
            drift[node_type] = {"error": "no outputSchema found for this node type", "keys": sorted(keys)}
            continue
        uncovered = sorted(k for k in keys if not key_covered(k, schema))
        if uncovered:
            drift[node_type] = {"uncovered": uncovered, "declared": schema["properties"], "file": schema["file"]}

    all_types = set(schemas.keys()) - {"utils-test"}
    covered_types = set(observed_by_type.keys())
    uncovered_types = sorted(all_types - covered_types)

    print(f"observed {len(covered_types)}/{len(all_types)} node types across {len(cases) - len(skipped) - len(errors)} fixtures "
          f"({len(skipped)} skipped, {len(errors)} errored)")
    if uncovered_types:
        print("\nno completed execution observed for (not necessarily a problem - just not checked this run):")
        for t in uncovered_types:
            print(f"  {t}")

    if errors:
        print("\nfixtures that errored out (investigate separately, not counted as drift):")
        for e in errors:
            print(f"  {e}")

    if not drift:
        print("\nno drift: every observed output key is covered by its node's outputSchema")
        return 0

    print(f"\nDRIFT in {len(drift)} node type(s):")
    for node_type, info in drift.items():
        if "error" in info:
            print(f"  {node_type}: {info['error']} (keys seen: {', '.join(info['keys'])})")
            continue
        print(f"  {node_type} ({info['file']}):")
        print(f"    schema declares: {', '.join(info['declared']) or '(none)'}")
        print(f"    undeclared keys actually returned: {', '.join(info['uncovered'])}")
    return 1


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