from __future__ import annotations

import argparse
import json
import sys
from collections.abc import Callable
from pathlib import Path
from typing import Any

from .api import serve
from .service import (
    CanonServiceError,
    alignment_template,
    artifact_graph,
    generate_agent_briefs,
    generate_indexes,
    generate_tree,
    inspect_canon,
    list_artifacts,
    list_models,
    list_standards,
    list_views,
    profile_graph,
    profile_inspect,
    profile_validate,
    read_view,
    review_capability_record,
    review_kit,
    validate_canon,
    write_validation_report,
)


Command = Callable[[argparse.Namespace], dict[str, Any]]


def build_parser() -> argparse.ArgumentParser:
    parser = argparse.ArgumentParser(prog="info-tech-canon")
    parser.add_argument(
        "--root",
        default="",
        help="Infospace root. Defaults to ./infospace from the repository root.",
    )
    sub = parser.add_subparsers(dest="command", required=True)

    inspect = sub.add_parser("inspect", help="Inspect the canon infospace")
    inspect.set_defaults(handler=_inspect)

    artifacts = sub.add_parser("artifacts", help="List canon artifacts")
    artifacts.add_argument("--kind", default="")
    artifacts.set_defaults(handler=_artifacts)

    models = sub.add_parser("models", help="List canon model artifacts")
    models.set_defaults(handler=_models)

    standards = sub.add_parser("standards", help="List canon standard artifacts")
    standards.set_defaults(handler=_standards)

    review_kit_cmd = sub.add_parser(
        "review-kit",
        help="Read the consumer repository alignment review kit",
    )
    review_kit_cmd.set_defaults(handler=_review_kit)

    alignment_template_cmd = sub.add_parser(
        "alignment-template",
        help="Read the consumer alignment workplan template",
    )
    alignment_template_cmd.set_defaults(handler=_alignment_template)

    validate = sub.add_parser("validate", help="Validate the canon infospace")
    validate.add_argument(
        "--write",
        default="",
        help="Write the JSON validation payload to this path.",
    )
    validate.set_defaults(handler=_validate)

    index = sub.add_parser("index", help="Refresh generated indexes and views")
    index.set_defaults(handler=_index)

    tree = sub.add_parser("tree", help="Refresh the generated infospace tree")
    tree.set_defaults(handler=_tree)

    agent_briefs = sub.add_parser("agent-briefs", help="Refresh generated agent briefs")
    agent_briefs.set_defaults(handler=_agent_briefs)

    views = sub.add_parser("views", help="List or read generated views")
    views.add_argument("name", nargs="?", default="")
    views.set_defaults(handler=_views)

    graph = sub.add_parser("graph", help="Export the canon artifact graph")
    graph.add_argument("--format", choices=["json", "mermaid"], default="json")
    graph.set_defaults(handler=_graph)

    profile = sub.add_parser("profile", help="Inspect canon profiles")
    profile_sub = profile.add_subparsers(dest="profile_command", required=True)
    profile_inspect_cmd = profile_sub.add_parser("inspect", help="Inspect a profile")
    profile_inspect_cmd.add_argument("profile")
    profile_inspect_cmd.set_defaults(handler=_profile_inspect)
    profile_validate_cmd = profile_sub.add_parser("validate", help="Validate a profile")
    profile_validate_cmd.add_argument("profile")
    profile_validate_cmd.set_defaults(handler=_profile_validate)
    profile_graph_cmd = profile_sub.add_parser("graph", help="Export a profile graph")
    profile_graph_cmd.add_argument("profile")
    profile_graph_cmd.add_argument("--format", choices=["json", "mermaid"], default="json")
    profile_graph_cmd.set_defaults(handler=_profile_graph)

    capability_review = sub.add_parser(
        "capability-review",
        help="Review a consumer capability record against the live catalog",
    )
    capability_review.add_argument("record")
    capability_review.set_defaults(handler=_capability_review)

    emission = sub.add_parser("emission-review", help="Validate a source-owned YAML/JSON cadence declaration")
    emission.add_argument("record")
    emission.set_defaults(handler=_emission_review)
    coverage = sub.add_parser("validation-coverage", help="List implemented checks and explicit limits")
    coverage.set_defaults(handler=_coverage)
    freshness = sub.add_parser("check-generated", help="Check projections without changing source files")
    freshness.set_defaults(handler=_check_generated)
    inventory = sub.add_parser("scope-inventory", help="Derive scope counts from the artifact registry")
    inventory.set_defaults(handler=_scope_inventory)
    bundle = sub.add_parser("export-emission-contract", help="Export a content-addressed contract tar")
    bundle.add_argument("destination")
    bundle.set_defaults(handler=_export_emission)
    benchmark = sub.add_parser("benchmark-reads", help="Measure ten uncached inspect calls")
    benchmark.set_defaults(handler=_benchmark_reads)

    api = sub.add_parser("api", help="Run the read-only local API")
    api.add_argument("--host", default="127.0.0.1")
    api.add_argument("--port", type=int, default=8765)
    api.set_defaults(handler=_api)

    return parser


def main(argv: list[str] | None = None) -> int:
    parser = build_parser()
    args = parser.parse_args(argv)
    handler: Command = args.handler
    try:
        result = handler(args)
    except CanonServiceError as exc:
        _print_json(exc.to_dict())
        return 2
    except Exception as exc:
        _print_json(
            {
                "ok": False,
                "error": {
                    "code": "unhandled_error",
                    "message": str(exc),
                    "details": {},
                },
            }
        )
        return 1
    if result:
        _print_json(result)
    return 0 if result.get("ok", False) else 1


def _root(args: argparse.Namespace) -> Path | None:
    return Path(args.root) if args.root else None


def _inspect(args: argparse.Namespace) -> dict[str, Any]:
    return inspect_canon(_root(args))


def _artifacts(args: argparse.Namespace) -> dict[str, Any]:
    return list_artifacts(_root(args), kind=args.kind or None)


def _models(args: argparse.Namespace) -> dict[str, Any]:
    return list_models(_root(args))


def _standards(args: argparse.Namespace) -> dict[str, Any]:
    return list_standards(_root(args))


def _review_kit(args: argparse.Namespace) -> dict[str, Any]:
    return review_kit(_root(args))


def _alignment_template(args: argparse.Namespace) -> dict[str, Any]:
    return alignment_template(_root(args))


def _validate(args: argparse.Namespace) -> dict[str, Any]:
    if args.write:
        return write_validation_report(args.write, _root(args))
    return validate_canon(_root(args))


def _index(args: argparse.Namespace) -> dict[str, Any]:
    return generate_indexes(_root(args))


def _tree(args: argparse.Namespace) -> dict[str, Any]:
    return generate_tree(_root(args))


def _agent_briefs(args: argparse.Namespace) -> dict[str, Any]:
    return generate_agent_briefs(_root(args))


def _views(args: argparse.Namespace) -> dict[str, Any]:
    if args.name:
        return read_view(args.name, _root(args))
    return list_views(_root(args))


def _graph(args: argparse.Namespace) -> dict[str, Any]:
    return artifact_graph(_root(args), output_format=args.format)


def _capability_review(args: argparse.Namespace) -> dict[str, Any]:
    return review_capability_record(args.record, _root(args))


def _emission_review(args):
    from .contracts import review_emission
    return review_emission(args.record, _root(args))


def _coverage(args):
    from .contracts import coverage
    from .service import load_context
    return coverage(load_context(_root(args)))


def _check_generated(args):
    from .maintenance import check_generated
    from .service import load_context
    return check_generated(load_context(_root(args)))


def _scope_inventory(args):
    from .maintenance import scope_inventory
    from .service import load_context
    return dict(scope_inventory(load_context(_root(args))), ok=True)


def _export_emission(args):
    from .maintenance import export_emission_bundle
    from .paths import infospace_root
    return export_emission_bundle(infospace_root(_root(args)), Path(args.destination))


def _benchmark_reads(args):
    from .maintenance import benchmark_reads
    from .paths import infospace_root
    return benchmark_reads(infospace_root(_root(args)))


def _profile_inspect(args: argparse.Namespace) -> dict[str, Any]:
    return profile_inspect(args.profile, _root(args))


def _profile_validate(args: argparse.Namespace) -> dict[str, Any]:
    return profile_validate(args.profile, _root(args))


def _profile_graph(args: argparse.Namespace) -> dict[str, Any]:
    return profile_graph(args.profile, _root(args), output_format=args.format)


def _api(args: argparse.Namespace) -> dict[str, Any]:
    serve(host=args.host, port=args.port, root=_root(args))
    return {}


def _print_json(data: dict[str, Any]) -> None:
    json.dump(data, sys.stdout, indent=2, sort_keys=True)
    sys.stdout.write("\n")