"""One-shot preprocessing commands."""

from __future__ import annotations

import json
import re
import hashlib
from pathlib import Path

import typer

from tht.cli.config_cmd import CONFIG_OPT


preprocess_app = typer.Typer(help="Materialize versioned preprocessing artifacts")


def run_from_config(config: Path, *, dry_run: bool = False, resume: str | None = None):
    from tht.adapters.factory import build_evidence_sources, build_vector_store
    from tht.cli.schema_cmd import _load_config_or_exit
    from tht.cli.vector_cmd import make_embedder
    from tht.corpus.chunk import ChunkPolicy
    from tht.corpus.pipeline import CorpusPipeline
    from tht.corpus.store import CorpusStore

    cfg = _load_config_or_exit(config)
    if cfg.embeddings is None:
        raise RuntimeError("embeddings are not configured")
    corpus_root = cfg.paths.artifacts.parent / "corpus"
    pipeline = CorpusPipeline(
        store=CorpusStore(corpus_root), sources=build_evidence_sources(cfg),
        embedder=make_embedder(cfg.embeddings),
        vector_store=build_vector_store(cfg, require_write=True),
        embedding_model=cfg.embeddings.model, embedding_dimensions=cfg.embeddings.dim,
        chunk_policy=ChunkPolicy(version="chunk-v1", max_chars=cfg.vector.max_chunk_chars),
        pipeline_version="evidence-v1",
        retain_published_generations=cfg.vector.retain_published_generations,
    )
    def fingerprint(value: str) -> str:
        return "sha256:" + hashlib.sha256(value.encode()).hexdigest()

    return pipeline.run_as_job(
        workspace_id=config.stem.lower().replace(".", "-").replace("_", "-"),
        workspace_root=corpus_root.parent,
        config_fingerprint=fingerprint(cfg.model_dump_json()),
        input_fingerprint=fingerprint(config.resolve().as_posix()),
        dry_run=dry_run,
        resume_run_id=resume,
    )


def gc_from_config(config: Path, *, dry_run: bool = False):
    from tht.adapters.factory import build_evidence_sources, build_vector_store
    from tht.cli.schema_cmd import _load_config_or_exit
    from tht.cli.vector_cmd import make_embedder
    from tht.corpus.chunk import ChunkPolicy
    from tht.corpus.pipeline import CorpusPipeline
    from tht.corpus.store import CorpusStore

    cfg = _load_config_or_exit(config)
    if cfg.embeddings is None:
        raise RuntimeError("embeddings are not configured")
    corpus_root = cfg.paths.artifacts.parent / "corpus"
    pipeline = CorpusPipeline(
        store=CorpusStore(corpus_root), sources=build_evidence_sources(cfg),
        embedder=make_embedder(cfg.embeddings), vector_store=build_vector_store(cfg, require_write=True),
        embedding_model=cfg.embeddings.model, embedding_dimensions=cfg.embeddings.dim,
        chunk_policy=ChunkPolicy(version="chunk-v1", max_chars=cfg.vector.max_chunk_chars),
        pipeline_version="evidence-v1",
        retain_published_generations=cfg.vector.retain_published_generations,
    )
    with pipeline.store.writer_lock():
        return pipeline.gc(workspace_root=corpus_root.parent, dry_run=dry_run)


@preprocess_app.command("evidence")
def evidence_cmd(
    action: str | None = typer.Argument(None),
    config: Path = CONFIG_OPT,
    dry_run: bool = typer.Option(False, "--dry-run"),
    resume: str | None = typer.Option(None, "--resume"),
    json_output: bool = typer.Option(False, "--json"),
) -> None:
    if action is not None and action != "gc":
        raise typer.BadParameter("only the optional 'gc' action is supported")
    if action == "gc":
        try:
            payload = gc_from_config(config, dry_run=dry_run)
        except Exception:
            payload = {"status": "failed", "error": "evidence cleanup failed"}
            if json_output:
                typer.echo(json.dumps(payload, sort_keys=True))
            else:
                typer.secho("ERRORE: evidence cleanup failed", fg=typer.colors.RED, err=True)
            raise typer.Exit(code=1) from None
        if json_output:
            typer.echo(json.dumps(payload, ensure_ascii=False, sort_keys=True))
        else:
            typer.echo(f"OK: evicted={len(payload['evicted'])} failures={len(payload['failures'])}")
        return
    if resume is not None and re.fullmatch(r"[0-9a-f]{32}", resume) is None:
        payload = {"status": "failed", "error": "resume requires a preprocessing run id"}
        if json_output:
            typer.echo(json.dumps(payload, sort_keys=True))
        else:
            typer.secho("ERRORE: resume requires a preprocessing run id", fg=typer.colors.RED, err=True)
        raise typer.Exit(code=2)
    try:
        result = run_from_config(config, dry_run=dry_run, resume=resume)
    except Exception:
        payload = {"status": "failed", "error": "preprocessing failed"}
        if json_output:
            typer.echo(json.dumps(payload, sort_keys=True))
        else:
            typer.secho("ERRORE: preprocessing failed", fg=typer.colors.RED, err=True)
        raise typer.Exit(code=1) from None
    payload = result.model_dump(mode="json")
    if json_output:
        typer.echo(json.dumps(payload, ensure_ascii=False, sort_keys=True))
    else:
        typer.echo(
            f"OK: run={payload['run_id']} generation={payload['generation']} changed={len(payload['changed'])} "
            f"unchanged={len(payload['unchanged'])} removed={len(payload['removed'])}"
        )