"""CLI for the DataTools Automated Workflows tool (script 09).

Usage:
    # Run the recommended default pipeline (text → format → missing → dedup):
    python -m src.cli_pipeline input.csv --apply

    # Quick custom order via --steps:
    python -m src.cli_pipeline input.csv \\
        --steps text_clean,format_standardize,missing --apply

    # Save the recommended pipeline to a JSON for editing:
    python -m src.cli_pipeline --recommend --output pipeline.json

    # Run a saved pipeline:
    python -m src.cli_pipeline weekly_export.csv --pipeline pipeline.json --apply

    # Strict mode: fail if the pipeline contains soft-dependency violations
    python -m src.cli_pipeline data.csv --steps dedup,text_clean \\
        --strict --apply
"""

from __future__ import annotations

import json
import sys
from datetime import datetime
from pathlib import Path
from typing import Optional

import typer
from loguru import logger

app = typer.Typer(
    name="pipeline",
    help=(
        "Chain DataTools cleaning steps into one orchestrated workflow.\n\n"
        "Default behaviour: preview the plan + run the pipeline (no file "
        "written). Add --apply to write the cleaned output and audit log.\n\n"
        "The pipeline RECOMMENDS an order based on tool dependencies "
        "(text-clean before format-standardize, format before dedup, etc.) "
        "and WARNS on out-of-order configs but does not block them. Use "
        "--strict to escalate warnings to errors.\n\n"
        "Tools available: text_clean, format_standardize, missing, "
        "column_map, dedup."
    ),
    add_completion=False,
    no_args_is_help=False,
)


# ---------------------------------------------------------------------------
# Helpers
# ---------------------------------------------------------------------------

def _setup_logging(log_dir: Path) -> Path:
    log_dir.mkdir(parents=True, exist_ok=True)
    ts = datetime.now().strftime("%Y%m%d_%H%M%S")
    log_path = log_dir / f"pipeline_{ts}.log"
    logger.remove()
    logger.add(sys.stderr, level="WARNING", format="{message}")
    logger.add(
        str(log_path), level="DEBUG",
        format="{time:YYYY-MM-DD HH:mm:ss} | {level:<8} | {message}",
    )
    return log_path


def _split_csv_arg(raw: Optional[str]) -> Optional[list[str]]:
    if raw is None:
        return None
    return [c.strip() for c in raw.split(",") if c.strip()]


# ---------------------------------------------------------------------------
# Main command
# ---------------------------------------------------------------------------

@app.command()
def run(
    input_file: Optional[str] = typer.Argument(
        None,
        help="CSV / TSV / Excel file. Optional with --recommend.",
    ),
    pipeline_path: Optional[str] = typer.Option(
        None, "--pipeline", "-p",
        help="Path to a pipeline JSON file (Pipeline.from_file format).",
    ),
    steps: Optional[str] = typer.Option(
        None, "--steps",
        help=(
            "Quick pipeline: comma-separated tool names in execution order. "
            "Each step uses defaults. Example: 'text_clean,format_standardize,dedup'."
        ),
    ),
    recommend: bool = typer.Option(
        False, "--recommend",
        help="Print (or save) the recommended default pipeline and exit.",
    ),
    output: Optional[str] = typer.Option(
        None, "--output", "-o",
        help=(
            "When --recommend is set, save the pipeline JSON here. "
            "Otherwise, write the pipeline output to this CSV path "
            "(default: {input}_pipeline.csv)."
        ),
    ),
    apply: bool = typer.Option(
        False, "--apply",
        help="Write the output. Without this flag, only the plan is shown.",
    ),
    strict: bool = typer.Option(
        False, "--strict",
        help="Treat soft-dependency warnings as errors (refuse to run).",
    ),
    continue_on_error: bool = typer.Option(
        False, "--continue-on-error",
        help="Don't abort if a step fails; carry the previous step's df forward.",
    ),
    encoding_override: Optional[str] = typer.Option(
        None, "--encoding",
        help="Override auto-detected file encoding.",
    ),
    delimiter: Optional[str] = typer.Option(
        None, "--delimiter",
        help="Override auto-detected delimiter.",
    ),
):
    """Run a DataTools cleaning pipeline."""
    from src.core.pipeline import (
        Pipeline,
        recommended_pipeline,
        run_pipeline,
        validate_pipeline,
    )

    # ------------------------------------------------------------------
    # --recommend: print or save the default pipeline and exit
    # ------------------------------------------------------------------
    if recommend:
        pipe = recommended_pipeline()
        body = json.dumps(pipe.to_dict(), indent=2)
        if output:
            Path(output).write_text(body)
            typer.echo(f"Recommended pipeline saved to {output}")
        else:
            typer.echo(body)
        return

    if not input_file:
        typer.echo(
            "Error: input file is required (or use --recommend to "
            "emit the default pipeline).",
            err=True,
        )
        raise typer.Exit(2)

    inp = Path(input_file)
    if not inp.exists():
        typer.echo(f"Error: File not found: {inp}", err=True)
        raise typer.Exit(1)

    log_path = _setup_logging(Path("logs"))

    # ------------------------------------------------------------------
    # Resolve pipeline source: --pipeline file, --steps list, or default
    # ------------------------------------------------------------------
    if pipeline_path and steps:
        typer.echo(
            "Error: pass either --pipeline or --steps, not both.",
            err=True,
        )
        raise typer.Exit(1)

    if pipeline_path:
        pp = Path(pipeline_path)
        if not pp.exists():
            typer.echo(f"Error: pipeline file not found: {pp}", err=True)
            raise typer.Exit(1)
        try:
            pipe = Pipeline.from_file(pp)
        except Exception as e:
            from src.core.errors import format_for_user
            typer.echo(f"Error reading pipeline: {format_for_user(e)}", err=True)
            raise typer.Exit(1)
    elif steps:
        names = _split_csv_arg(steps) or []
        try:
            pipe = recommended_pipeline(include=names)
        except Exception as e:
            from src.core.errors import format_for_user
            typer.echo(f"Error: {format_for_user(e)}", err=True)
            raise typer.Exit(1)
    else:
        pipe = recommended_pipeline()

    # ------------------------------------------------------------------
    # Plan + warnings
    # ------------------------------------------------------------------
    warnings = validate_pipeline(pipe)
    typer.echo(f"\n{'─'*60}")
    typer.echo("  Pipeline plan:")
    for i, step in enumerate(pipe.steps, 1):
        flag = "  " if step.enabled else "✗ "
        typer.echo(f"  {i}. {flag}{step.display_name():<22} options={step.options or {}}")
    typer.echo(f"{'─'*60}")
    if warnings:
        typer.echo("\nSoft-dependency warnings (recommended order violated):")
        for w in warnings:
            typer.echo(f"  ! {w}")
        if strict:
            typer.echo(
                "\nAborting: --strict was set. Reorder the steps or drop --strict.",
                err=True,
            )
            raise typer.Exit(2)

    if not apply:
        typer.echo(
            "\nThis was a plan-only run. Add --apply to execute the pipeline."
        )
        typer.echo(f"Log: {log_path}")
        return

    # ------------------------------------------------------------------
    # Read input + execute
    # ------------------------------------------------------------------
    from src.core.io import read_file, write_file
    import pandas as pd

    typer.echo(f"\nReading {inp.name}...")
    try:
        df = read_file(
            inp, encoding=encoding_override, delimiter=delimiter, repair=False,
        )
        if not isinstance(df, pd.DataFrame):
            df = pd.concat(list(df), ignore_index=True)
    except Exception as e:
        typer.echo(f"Error reading file: {e}", err=True)
        raise typer.Exit(1)

    typer.echo(f"  {len(df):,} rows, {len(df.columns)} columns")

    typer.echo("\nExecuting pipeline:")

    def _on_step(sr) -> None:
        if sr.skipped:
            typer.echo(f"  - {sr.step.display_name()} (skipped)")
        elif sr.error:
            typer.echo(f"  ✗ {sr.step.display_name()} ({sr.elapsed_seconds*1000:.0f} ms) — ERROR: {sr.error.splitlines()[0]}")
        else:
            typer.echo(f"  ✓ {sr.step.display_name()} ({sr.elapsed_seconds*1000:.0f} ms) {sr.summary}")

    try:
        result = run_pipeline(
            df, pipe,
            on_step_complete=_on_step,
            stop_on_error=not continue_on_error,
        )
    except Exception as e:
        from src.core.errors import format_for_user
        typer.echo(f"\nPipeline halted: {format_for_user(e)}", err=True)
        raise typer.Exit(1)

    typer.echo(f"\n{'─'*60}")
    typer.echo(f"  Initial rows:  {result.initial_rows:,}")
    typer.echo(f"  Final rows:    {result.final_rows:,}")
    typer.echo(f"  Steps run:     {sum(1 for s in result.step_results if not s.skipped)}")
    typer.echo(f"  Total elapsed: {result.total_elapsed:.2f} s")
    typer.echo(f"{'─'*60}")

    # ------------------------------------------------------------------
    # Write output + audit
    # ------------------------------------------------------------------
    out_path = Path(output) if output else inp.parent / f"{inp.stem}_pipeline.csv"
    write_file(result.final_df, out_path)
    typer.echo(f"\nPipeline output:  {out_path}")

    audit_path = inp.parent / f"{inp.stem}_pipeline.json"
    audit_path.write_text(json.dumps({
        "pipeline": pipe.to_dict(),
        "warnings": result.warnings,
        "initial_rows": result.initial_rows,
        "final_rows": result.final_rows,
        "total_elapsed_seconds": result.total_elapsed,
        "steps": [
            {
                "tool": sr.step.tool,
                "name": sr.step.display_name(),
                "enabled": sr.step.enabled,
                "skipped": sr.skipped,
                "elapsed_seconds": sr.elapsed_seconds,
                "summary": sr.summary,
                "error": sr.error,
            }
            for sr in result.step_results
        ],
    }, indent=2, default=str))
    typer.echo(f"Pipeline audit:   {audit_path}")
    typer.echo(f"Log:              {log_path}")


def main() -> None:
    from src.cli_license_guard import guard
    from src.license import FeatureFlag
    guard(feature=FeatureFlag.PIPELINE_RUNNER.value)
    app()


if __name__ == "__main__":
    main()