"""Guide Board command line interface."""

from __future__ import annotations

import argparse
import json
import sys
from pathlib import Path
from typing import Any

from guide_board.discovery import discover_extensions
from guide_board.errors import GuideBoardError
from guide_board.execution import run_assessment
from guide_board.gates import evaluate_trend_gates
from guide_board.io import load_json, write_json
from guide_board.planning import (
    build_run_plan,
    validate_assessment_profile,
    validate_target_profile,
)
from guide_board.retention import build_trend_summary, list_retained_runs
from guide_board.schema import assert_valid
from guide_board.service import build_server


def main(argv: list[str] | None = None) -> int:
    parser = build_parser()
    args = parser.parse_args(argv)
    try:
        result = args.func(args)
    except GuideBoardError as exc:
        print(f"guide-board: {exc}", file=sys.stderr)
        return 2
    except (OSError, ValueError) as exc:
        print(f"guide-board: {exc}", file=sys.stderr)
        return 1

    if result is not None:
        print_json(result)
    return 0


def build_parser() -> argparse.ArgumentParser:
    parser = argparse.ArgumentParser(prog="guide-board")
    parser.add_argument("--root", type=Path, default=Path.cwd(), help="repository root")
    parser.add_argument(
        "--extension-dir",
        action="append",
        type=Path,
        help="external extension repo or directory containing extension repos",
    )
    subcommands = parser.add_subparsers(required=True)

    extensions = subcommands.add_parser("extensions", help="extension operations")
    extension_commands = extensions.add_subparsers(required=True)
    list_extensions = extension_commands.add_parser("list", help="list discovered extensions")
    list_extensions.set_defaults(func=cmd_extensions_list)
    validate_extensions = extension_commands.add_parser(
        "validate", help="validate discovered extension manifests"
    )
    validate_extensions.set_defaults(func=cmd_extensions_validate)

    profile = subcommands.add_parser("profile", help="profile validation")
    profile_commands = profile.add_subparsers(required=True)
    target = profile_commands.add_parser("validate-target", help="validate a target profile")
    target.add_argument("path", type=Path)
    target.set_defaults(func=cmd_validate_target)
    assessment = profile_commands.add_parser(
        "validate-assessment", help="validate an assessment profile"
    )
    assessment.add_argument("path", type=Path)
    assessment.set_defaults(func=cmd_validate_assessment)

    plan = subcommands.add_parser("plan", help="build a run plan")
    plan.add_argument("--target", type=Path, required=True)
    plan.add_argument("--assessment", type=Path, required=True)
    plan.add_argument("--output", type=Path)
    plan.set_defaults(func=cmd_plan)

    run = subcommands.add_parser("run", help="run the baseline assessment executor")
    run.add_argument("--target", type=Path, required=True)
    run.add_argument("--assessment", type=Path, required=True)
    run.add_argument("--output-dir", type=Path)
    run.set_defaults(func=cmd_run)

    serve = subcommands.add_parser("serve", help="serve the local HTTP API")
    serve.add_argument("--host", default="127.0.0.1")
    serve.add_argument("--port", type=int, default=8080)
    serve.set_defaults(func=cmd_serve)

    runs = subcommands.add_parser("runs", help="run history operations")
    runs_commands = runs.add_subparsers(required=True)
    list_runs = runs_commands.add_parser("list", help="list retained run summaries")
    list_runs.add_argument("--runs-dir", type=Path)
    list_runs.set_defaults(func=cmd_runs_list)
    trend_runs = runs_commands.add_parser("trend", help="summarize retained run trends")
    trend_runs.add_argument("--runs-dir", type=Path)
    trend_runs.set_defaults(func=cmd_runs_trend)
    gate_runs = runs_commands.add_parser("gate", help="evaluate retained run quality gates")
    gate_runs.add_argument("--runs-dir", type=Path)
    gate_runs.add_argument("--target")
    gate_runs.add_argument("--assessment")
    gate_runs.add_argument("--allowed-status", action="append")
    gate_runs.add_argument("--max-unexpected-findings", type=int, default=0)
    gate_runs.add_argument("--allow-regression", action="store_true")
    gate_runs.set_defaults(func=cmd_runs_gate)

    schema = subcommands.add_parser("schema", help="schema validation")
    schema.add_argument("schema_name")
    schema.add_argument("path", type=Path)
    schema.set_defaults(func=cmd_schema_validate)

    return parser


def cmd_extensions_list(args: argparse.Namespace) -> dict[str, Any]:
    extensions = discover_extensions(args.root, args.extension_dir)
    return {
        "extensions": [
            {
                "id": extension.id,
                "name": extension.manifest["name"],
                "version": extension.manifest["version"],
                "type": extension.manifest["extension_type"],
                "path": _display_path(args.root, extension.path),
                "source": extension.source,
            }
            for extension in extensions
        ]
    }


def cmd_extensions_validate(args: argparse.Namespace) -> dict[str, Any]:
    extensions = discover_extensions(args.root, args.extension_dir)
    return {
        "status": "valid",
        "extensions": [extension.id for extension in extensions],
    }


def cmd_validate_target(args: argparse.Namespace) -> dict[str, Any]:
    profile = validate_target_profile(args.path)
    return {"status": "valid", "target_profile": profile["id"]}


def cmd_validate_assessment(args: argparse.Namespace) -> dict[str, Any]:
    profile = validate_assessment_profile(args.path)
    return {"status": "valid", "assessment_profile": profile["id"]}


def cmd_plan(args: argparse.Namespace) -> dict[str, Any] | None:
    plan = build_run_plan(args.root, args.target, args.assessment, args.extension_dir)
    if args.output:
        write_json(args.output, plan)
        return {"status": "written", "path": str(args.output)}
    return plan


def cmd_run(args: argparse.Namespace) -> dict[str, Any]:
    return run_assessment(
        args.root,
        args.target,
        args.assessment,
        args.output_dir,
        args.extension_dir,
    )


def cmd_serve(args: argparse.Namespace) -> None:
    server = build_server(args.root, args.extension_dir, args.host, args.port)
    host, port = server.server_address
    print(f"guide-board: serving local API on http://{host}:{port}", file=sys.stderr)
    try:
        server.serve_forever()
    except KeyboardInterrupt:
        print("guide-board: stopping local API", file=sys.stderr)
    finally:
        server.server_close()
    return None


def cmd_runs_list(args: argparse.Namespace) -> dict[str, Any]:
    runs_dir = args.runs_dir or args.root / "runs"
    return {
        "runs_dir": str(runs_dir),
        "runs": list_retained_runs(runs_dir),
    }


def cmd_runs_trend(args: argparse.Namespace) -> dict[str, Any]:
    runs_dir = args.runs_dir or args.root / "runs"
    summary = build_trend_summary(runs_dir)
    assert_valid(summary, "trend-summary")
    return summary


def cmd_runs_gate(args: argparse.Namespace) -> dict[str, Any]:
    runs_dir = args.runs_dir or args.root / "runs"
    trend_summary = build_trend_summary(runs_dir)
    gate_summary = evaluate_trend_gates(
        trend_summary,
        allowed_statuses=args.allowed_status,
        max_unexpected_findings=args.max_unexpected_findings,
        fail_on_regression=not args.allow_regression,
        target_profile_ref=args.target,
        assessment_profile_ref=args.assessment,
    )
    assert_valid(gate_summary, "gate-summary")
    return gate_summary


def cmd_schema_validate(args: argparse.Namespace) -> dict[str, Any]:
    document = load_json(args.path)
    assert_valid(document, args.schema_name)
    return {"status": "valid", "schema": args.schema_name, "path": str(args.path)}


def print_json(value: Any) -> None:
    print(json.dumps(value, indent=2, sort_keys=True))


def _display_path(root: Path, path: Path) -> str:
    try:
        return str(path.resolve().relative_to(root.resolve()))
    except ValueError:
        return str(path.resolve())