#!/usr/bin/env python3
"""Validate the persistent continuous-execution checkpoint.

This is intentionally read-only. It cannot start a model/agent turn; it gives
an external scheduler or the next resumed turn a deterministic continuation
decision without changing task state.
"""
from __future__ import annotations

import argparse
import json
from pathlib import Path


ROOT = Path(__file__).resolve().parents[1]
CHECKPOINT = ROOT / "docs/current/continuation-state.json"
TASK_STATE = ROOT / "docs/current/task-state.json"
MODULE_BATCH = ROOT / "docs/current/module-batch-manifest.json"


def main() -> int:
    parser = argparse.ArgumentParser()
    parser.add_argument("--quiet", action="store_true")
    parser.add_argument("--json", action="store_true", help="emit a machine-readable result")
    args = parser.parse_args()
    checkpoint = json.loads(CHECKPOINT.read_text(encoding="utf-8"))
    task_state = json.loads(TASK_STATE.read_text(encoding="utf-8"))
    active = task_state.get("active_task")
    counts = task_state.get("counts", {})
    errors: list[str] = []
    if checkpoint.get("mode") != "continuous":
        errors.append("continuation mode is not continuous")
    if checkpoint.get("scope") != "full-project":
        errors.append("continuation scope is not full-project")
    allowed_scopes = {"all-task-cards-all-modules-all-required-y-gates"}
    if checkpoint.get("implementationStrategy", {}).get("mode") == "feature-first-deferred-validation":
        allowed_scopes.add("all-business-workflows-and-feature-routes")
    if checkpoint.get("completionScope") not in allowed_scopes:
        errors.append("completion scope is not the full project")
    if checkpoint.get("noPartialCompletion") is not True:
        errors.append("noPartialCompletion is not true")
    if checkpoint.get("autoAdvance") is not True:
        errors.append("autoAdvance is not true")
    if checkpoint.get("mustContinue") is not True:
        errors.append("mustContinue is not true")
    if checkpoint.get("noFinalBeforeTerminate") is not True:
        errors.append("noFinalBeforeTerminate is not true")
    if checkpoint.get("phaseTransitionPolicy") != "immediate":
        errors.append("phase transition policy is not immediate")
    if checkpoint.get("confirmationPolicy") != "never_for_in_scope":
        errors.append("confirmation policy is not never_for_in_scope")
    if checkpoint.get("pausePolicy") != "never_between_phases":
        errors.append("pause policy allows a phase pause")
    if checkpoint.get("waitingAllowed") is not False:
        errors.append("waitingAllowed must be false")
    if checkpoint.get("awaitConfirmation") is not False:
        errors.append("awaitConfirmation must be false")
    if not isinstance(checkpoint.get("automaticActions"), list) or not checkpoint.get("automaticActions"):
        errors.append("automaticActions is empty")
    required_actions = {"source edits", "native builds", "asset sync", "context rotation", "ledger sync", "task claim", "single retry after timeout", "recovery-card creation"}
    if not required_actions.issubset(set(checkpoint.get("automaticActions", []))):
        errors.append("automaticActions is missing required in-scope actions")
    allowed_pauses = {"missing credentials", "irreversible destructive action outside the requested repository scope", "new architecture decision that cannot be inferred from source"}
    if set(checkpoint.get("pauseOnlyFor", [])) != allowed_pauses:
        errors.append("pauseOnlyFor does not match the declared exception boundary")
    if not checkpoint.get("termination"):
        errors.append("termination policy is empty")
    batch_policy = checkpoint.get("batchPolicy")
    if not isinstance(batch_policy, dict):
        errors.append("batchPolicy is missing")
    else:
        if batch_policy.get("mode") != "module+tier+family":
            errors.append("batchPolicy mode is not module+tier+family")
        if int(batch_policy.get("minRecords", 0)) < 2:
            errors.append("batchPolicy minRecords must be at least 2")
        if int(batch_policy.get("defaultRecords", 0)) < int(batch_policy.get("minRecords", 0)):
            errors.append("batchPolicy defaultRecords is below minRecords")
        if int(batch_policy.get("maxRecords", 0)) < int(batch_policy.get("defaultRecords", 0)):
            errors.append("batchPolicy maxRecords is below defaultRecords")
        if batch_policy.get("manifest") != "docs/current/module-batch-manifest.json":
            errors.append("batchPolicy manifest is not the canonical module batch manifest")
    if checkpoint.get("batchManifest") != "docs/current/module-batch-manifest.json":
        errors.append("batchManifest is not the canonical module batch manifest")
    if active and not MODULE_BATCH.exists():
        errors.append("module-batch-manifest.json is missing for active task")
    elif active and MODULE_BATCH.exists():
        try:
            batch = json.loads(MODULE_BATCH.read_text(encoding="utf-8"))
            if batch.get("taskId") not in (None, active):
                errors.append("module batch manifest taskId does not match active task")
            if batch.get("status") == "ready":
                selected = batch.get("selected") if isinstance(batch.get("selected"), dict) else {}
                min_records = int(batch_policy.get("minRecords", 2)) if isinstance(batch_policy, dict) else 2
                if int(selected.get("recordCount", 0)) < min_records:
                    if batch.get("singletonFallback") is not True:
                        errors.append("module batch manifest has fewer records than batchPolicy minRecords without singletonFallback")
                if checkpoint.get("batchId") not in (None, batch.get("batchId")):
                    errors.append("continuation batchId does not match module batch manifest")
        except (OSError, json.JSONDecodeError, TypeError, ValueError):
            errors.append("module-batch-manifest.json is invalid")
    if checkpoint.get("activeTask") != active:
        errors.append(f"active task mismatch: checkpoint={checkpoint.get('activeTask')} ledger={active}")
    if counts.get("in_progress", 0) != 1:
        errors.append(f"expected exactly one in_progress task, got {counts.get('in_progress', 0)}")
    phases = {"LOAD_STATE", "VALIDATE", "PREPARE_CONTEXT", "READ_MANIFEST", "IMPLEMENT_BATCH", "RECORD_RESULT", "ROTATE_CONTEXT", "SYNC_STATE", "PREPARE_NEXT", "CONTINUE"}
    if checkpoint.get("phase") not in phases:
        errors.append(f"invalid continuation phase: {checkpoint.get('phase')}")
    if errors:
        if args.json:
            print(json.dumps({"schema": "freecad-web-continuation-check/v1", "ok": False, "activeTask": active, "errors": errors}, ensure_ascii=False))
            return 1
        if not args.quiet:
            for error in errors:
                print(f"CONTINUATION_STATE_INVALID: {error}")
        return 1
    if args.json:
        print(json.dumps({"schema": "freecad-web-continuation-check/v1", "ok": True, "activeTask": active, "phase": checkpoint.get("phase"), "mustContinue": True, "noFinalBeforeTerminate": True, "resumeCommand": checkpoint.get("resumeCommand", "")}, ensure_ascii=False))
    elif not args.quiet:
        print(f"CONTINUATION_STATE_READY: active={active} phase={checkpoint.get('phase')} mustContinue=true noFinalBeforeTerminate=true")
        print(f"RESUME_COMMAND: {checkpoint.get('resumeCommand', '')}")
    return 0


if __name__ == "__main__":
    raise SystemExit(main())