import argparse
import glob
import sys
from typing import List

import tabulate

from sglang.test.ci.ci_register import CIRegistry, HWBackend, collect_tests
from sglang.test.ci.ci_utils import run_unittest_files

HW_MAPPING = {
    "cpu": HWBackend.CPU,
    "cuda": HWBackend.CUDA,
    "amd": HWBackend.AMD,
    "npu": HWBackend.NPU,
}

# Per-commit test suites (run on every PR)
PER_COMMIT_SUITES = {
    HWBackend.CPU: ["default", "stage-a-cpu-only"],
    HWBackend.AMD: [
        "stage-a-test-1-amd",
        "stage-b-test-small-1-gpu-amd",
        "stage-b-test-small-1-gpu-amd-nondeterministic",
        "stage-b-test-small-1-gpu-amd-mi35x",
        "stage-b-test-large-8-gpu-35x-disaggregation-amd",
        "stage-b-test-large-1-gpu-amd",
        "stage-b-test-large-2-gpu-amd",
        "stage-c-test-large-8-gpu-amd",
        "stage-c-test-large-8-gpu-amd-mi35x",
    ],
    HWBackend.CUDA: [
        "stage-a-test-1",
        "stage-b-test-small-1-gpu",
        "stage-b-test-large-1-gpu",
        "stage-b-test-large-2-gpu",
        "stage-c-test-4-gpu-h100",
        "stage-c-test-4-gpu-b200",
        "stage-c-test-4-gpu-gb200",
        "stage-c-test-deepep-4-gpu",
        "stage-c-test-8-gpu-h20",
        "stage-c-test-8-gpu-h200",
        "stage-c-test-8-gpu-b200",
        "stage-c-test-deepep-8-gpu-h200",
    ],
    HWBackend.NPU: [
        "stage-a-test-1",
        "stage-b-test-1-npu-a2",
        "stage-b-test-2-npu-a2",
        "stage-b-test-4-npu-a3",
        "stage-b-test-16-npu-a3",
    ],
}

# Nightly test suites (run nightly, organized by GPU configuration)
NIGHTLY_SUITES = {
    HWBackend.CUDA: [
        "nightly-1-gpu",
        "nightly-2-gpu",
        "nightly-4-gpu",
        "nightly-4-gpu-b200",
        "nightly-8-gpu",
        "nightly-8-gpu-h200",
        "nightly-8-gpu-h20",
        "nightly-8-gpu-b200",
        "nightly-8-gpu-h200-basic",  # Basic tests for large models on H200
        "nightly-8-gpu-b200-basic",  # Basic tests for large models on B200
        "nightly-8-gpu-common",  # Common tests that run on both H200 and B200
        # Eval and perf suites (2-gpu)
        "nightly-eval-text-2-gpu",
        "nightly-eval-vlm-2-gpu",
        "nightly-perf-text-2-gpu",
        "nightly-perf-vlm-2-gpu",
    ],
    HWBackend.AMD: [
        "nightly-amd",
        "nightly-amd-1-gpu",
        "nightly-amd-1-gpu-mi35x",
        "nightly-amd-1-gpu-zimage-turbo",
        "nightly-amd-8-gpu",
        "nightly-amd-vlm",
        # MI35x 8-GPU suite (different model configs)
        "nightly-amd-8-gpu-mi35x",
    ],
    HWBackend.CPU: [],
    HWBackend.NPU: [
        "nightly-1-npu-a3",
        "nightly-2-npu-a3",
        "nightly-4-npu-a3",
        "nightly-8-npu-a3",
        "nightly-16-npu-a3",
    ],
}


def filter_tests(
    ci_tests: List[CIRegistry], hw: HWBackend, suite: str, nightly: bool = False
) -> List[CIRegistry]:
    ci_tests = [
        t
        for t in ci_tests
        if t.backend == hw and t.suite == suite and t.nightly == nightly
    ]

    valid_suites = (
        NIGHTLY_SUITES.get(hw, []) if nightly else PER_COMMIT_SUITES.get(hw, [])
    )

    if suite not in valid_suites:
        print(
            f"Warning: Unknown suite {suite} for backend {hw.name}, nightly={nightly}"
        )

    enabled_tests = [t for t in ci_tests if t.disabled is None]
    skipped_tests = [t for t in ci_tests if t.disabled is not None]

    return enabled_tests, skipped_tests


def auto_partition(files: List[CIRegistry], rank, size):
    """
    Partition files into size sublists with approximately equal sums of estimated times
    using a greedy algorithm (LPT heuristic), and return the partition for the specified rank.
    """
    if not files or size <= 0:
        return []

    # Sort files by estimated_time in descending order (LPT heuristic).
    # Use filename as tie-breaker to ensure deterministic partitioning
    # regardless of glob ordering.
    sorted_files = sorted(files, key=lambda f: (-f.est_time, f.filename))

    partitions = [[] for _ in range(size)]
    partition_sums = [0.0] * size

    # Greedily assign each file to the partition with the smallest current total time
    for file in sorted_files:
        min_sum_idx = min(range(size), key=partition_sums.__getitem__)
        partitions[min_sum_idx].append(file)
        partition_sums[min_sum_idx] += file.est_time

    if rank < size:
        return partitions[rank]
    return []


def pretty_print_tests(
    args, ci_tests: List[CIRegistry], skipped_tests: List[CIRegistry]
):
    hw = HW_MAPPING[args.hw]
    suite = args.suite
    nightly = args.nightly
    if args.auto_partition_size:
        partition_info = (
            f"{args.auto_partition_id + 1}/{args.auto_partition_size} "
            f"(0-based id={args.auto_partition_id})"
        )
    else:
        partition_info = "full"

    headers = ["Hardware", "Suite", "Nightly", "Partition"]
    rows = [[hw.name, suite, str(nightly), partition_info]]
    msg = tabulate.tabulate(rows, headers=headers, tablefmt="psql") + "\n"

    if skipped_tests:
        msg += f"⚠️  Skipped {len(skipped_tests)} test(s):\n"
        for t in skipped_tests:
            reason = t.disabled or "disabled"
            msg += f"  - {t.filename} (reason: {reason})\n"
        msg += "\n"

    if len(ci_tests) == 0:
        msg += f"No tests found for hw={hw.name}, suite={suite}, nightly={nightly}\n"
        msg += "This is expected during incremental migration. Skipping.\n"
    else:
        total_est_time = sum(t.est_time for t in ci_tests)
        msg += (
            f"✅ Enabled {len(ci_tests)} test(s) (est total {total_est_time:.1f}s):\n"
        )
        for t in ci_tests:
            msg += f"  - {t.filename} (est_time={t.est_time})\n"

    print(msg, flush=True)


def run_a_suite(args):
    hw = HW_MAPPING[args.hw]
    suite = args.suite
    nightly = args.nightly
    auto_partition_id = args.auto_partition_id
    auto_partition_size = args.auto_partition_size

    # All tests (per-commit and nightly) are now in registered/
    files = [
        f
        for f in glob.glob("registered/**/*.py", recursive=True)
        if not f.endswith("/conftest.py") and not f.endswith("/__init__.py")
    ]
    # Strict: all registered files must have proper registration
    sanity_check = True

    all_tests = collect_tests(files, sanity_check=sanity_check)
    ci_tests, skipped_tests = filter_tests(all_tests, hw, suite, nightly)

    if auto_partition_size:
        ci_tests = auto_partition(ci_tests, auto_partition_id, auto_partition_size)

    pretty_print_tests(args, ci_tests, skipped_tests)

    # Add extra timeout when retry is enabled
    timeout = args.timeout_per_file
    if args.enable_retry:
        timeout += args.retry_timeout_increase

    return run_unittest_files(
        ci_tests,
        timeout_per_file=timeout,
        continue_on_error=args.continue_on_error,
        enable_retry=args.enable_retry,
        max_attempts=args.max_attempts,
        retry_wait_seconds=args.retry_wait_seconds,
    )


def main():
    parser = argparse.ArgumentParser(
        description="Run CI test suites from test/registered/"
    )
    parser.add_argument(
        "--hw",
        type=str,
        choices=HW_MAPPING.keys(),
        required=True,
        help="Hardware backend to run tests on.",
    )
    parser.add_argument("--suite", type=str, required=True, help="Test suite to run.")
    parser.add_argument(
        "--nightly",
        action="store_true",
        help="Run nightly tests instead of per-commit tests.",
    )
    parser.add_argument(
        "--timeout-per-file",
        type=int,
        default=1200,
        help="The time limit for running one file in seconds (default: 1200).",
    )
    parser.add_argument(
        "--continue-on-error",
        action="store_true",
        default=False,
        help="Continue running remaining tests even if one fails (default: False, useful for nightly tests).",
    )
    parser.add_argument(
        "--auto-partition-id",
        type=int,
        help="Use auto load balancing. The part id.",
    )
    parser.add_argument(
        "--auto-partition-size",
        type=int,
        help="Use auto load balancing. The number of parts.",
    )
    parser.add_argument(
        "--enable-retry",
        action="store_true",
        default=False,
        help="Enable smart retry for accuracy/performance assertion failures (not code errors)",
    )
    parser.add_argument(
        "--max-attempts",
        type=int,
        default=2,
        help="Maximum number of attempts per file including initial run (default: 2)",
    )
    parser.add_argument(
        "--retry-wait-seconds",
        type=int,
        default=60,
        help="Seconds to wait between retries (default: 60)",
    )
    parser.add_argument(
        "--retry-timeout-increase",
        type=int,
        default=600,
        help="Additional timeout in seconds when retry is enabled (default: 600)",
    )
    args = parser.parse_args()

    # Validate auto-partition arguments
    if (args.auto_partition_id is not None) != (args.auto_partition_size is not None):
        parser.error(
            "--auto-partition-id and --auto-partition-size must be specified together."
        )
    if args.auto_partition_size is not None:
        if args.auto_partition_size <= 0:
            parser.error("--auto-partition-size must be positive.")
        if not 0 <= args.auto_partition_id < args.auto_partition_size:
            parser.error(
                f"--auto-partition-id must be in range [0, {args.auto_partition_size}), "
                f"but got {args.auto_partition_id}"
            )

    exit_code = run_a_suite(args)
    sys.exit(exit_code)


if __name__ == "__main__":
    main()