"""Job listing, labels, and JSON payloads shared by the HTML UI and /api."""

from __future__ import annotations

import re
import uuid
from datetime import UTC, datetime
from pathlib import Path
from typing import Any

from fastapi import HTTPException

from . import config, images, pipeline

_JOB_ID_RE = re.compile(r"^[A-Za-z0-9._-]+$")

STATUS_LABELS: dict[str, str] = {
    "queued": "Warteschlange",
    "processing": "Läuft",
    "done": "Fertig",
    "error": "Fehler",
    "unknown": "unbekannt",
}

ACTIVE_STATUSES = frozenset({"queued", "processing", "pending"})


class JobIdError(ValueError):
    """Invalid or missing job id."""


def validate_job_id(job_id: str) -> str:
    raw = job_id or ""
    if not raw.strip() or "/" in raw or "\\" in raw or ".." in raw:
        raise JobIdError("Ungültige Job-ID")
    stem = pipeline.sanitize_stem(raw)
    if not _JOB_ID_RE.match(stem):
        raise JobIdError("Ungültige Job-ID")
    return stem


def require_job_id(job_id: str) -> str:
    try:
        stem = validate_job_id(job_id)
    except JobIdError as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc
    if pipeline.read_status(stem) is None and not pipeline.job_paths(stem).original.exists():
        raise HTTPException(status_code=404, detail="Job nicht gefunden")
    return stem


def status_label(status: str | None) -> str:
    key = (status or "unknown").strip() or "unknown"
    return STATUS_LABELS.get(key, key)


def stage_label(status: str | None, stage: str | None, progress: dict[str, Any] | None) -> str:
    if status == "queued":
        return "Wartet auf Worker"
    if status == "done":
        return "Fertig"
    if status == "error":
        return "Fehler"
    if stage == "preprocess":
        return "Vorverarbeitung"
    if stage == "rembg":
        return "Freistellen"
    if stage == "variant":
        current = (progress or {}).get("current")
        total = (progress or {}).get("total")
        if current and total:
            return f"Variante {current}/{total}"
        return "Varianten"
    if status == "processing":
        return "Läuft"
    return status_label(status)


def file_url(job_id: str, filename: str | None) -> str | None:
    if not filename:
        return None
    return images.file_url(job_id, filename)


def list_intermediates(stem: str) -> list[str]:
    paths = pipeline.job_paths(stem)
    if not paths.intermediates.exists():
        return []
    return sorted(p.name for p in paths.intermediates.glob(f"{stem}_*.png") if p.is_file())


def _progress(data: dict[str, Any]) -> dict[str, int] | None:
    raw = data.get("progress")
    if not isinstance(raw, dict):
        return None
    try:
        current = int(raw.get("current", 0))
        total = int(raw.get("total", 0))
    except (TypeError, ValueError):
        return None
    if total <= 0:
        return None
    return {"current": current, "total": total}


def _file_entry(job_id: str, filename: str | None) -> dict[str, str] | None:
    if not filename:
        return None
    return {"file": filename, "url": images.file_url(job_id, filename)}


def summarize_job(job_id: str, data: dict[str, Any] | None = None) -> dict[str, Any]:
    meta = data if data is not None else (pipeline.read_meta(job_id) or {})
    variants = meta.get("variants") or []
    status = meta.get("status", "unknown")
    progress = _progress(meta)
    stage = meta.get("stage")
    thumb = variants[-1].get("file") if variants else None
    return {
        "job_id": job_id,
        "status": status,
        "status_label": status_label(status),
        "stage": stage,
        "stage_label": stage_label(status, stage if isinstance(stage, str) else None, progress),
        "progress": progress,
        "created_at": meta.get("created_at") or "",
        "updated_at": meta.get("updated_at") or "",
        "variant_count": len(variants),
        "thumbnail": thumb,
        "thumbnail_url": file_url(job_id, thumb),
        "error": meta.get("error"),
    }


def list_jobs() -> list[dict[str, Any]]:
    jobs = [summarize_job(job_id) for job_id in pipeline.list_job_ids()]
    jobs.sort(key=lambda j: j["created_at"] or j["job_id"], reverse=True)
    return jobs


def job_detail_payload(job_id: str) -> dict[str, Any]:
    stem = require_job_id(job_id)
    meta = pipeline.read_meta(stem) or {}
    paths = pipeline.job_paths(stem)
    summary = summarize_job(stem, meta)
    variants = []
    for item in meta.get("variants") or []:
        if not isinstance(item, dict) or not item.get("file"):
            continue
        entry = dict(item)
        entry["url"] = images.file_url(stem, item["file"])
        variants.append(entry)
    intermediates = [_file_entry(stem, name) for name in list_intermediates(stem)]
    original_name = paths.original.name if paths.original.exists() else meta.get("original_file")
    rembg_name = paths.rembg.name if paths.rembg.exists() else meta.get("rembg_file")
    summary.update(
        {
            "original": _file_entry(stem, original_name if original_name else None),
            "rembg": _file_entry(stem, rembg_name if rembg_name else None),
            "has_rembg": paths.rembg.exists(),
            "variants": variants,
            "intermediates": [item for item in intermediates if item],
            "variant_errors": meta.get("variant_errors") or [],
            "source_file": meta.get("source_file"),
        }
    )
    return summary


def make_inbox_filename(original_name: str) -> str:
    """Unique inbox name so two party.jpg uploads don't clobber each other."""
    stem = pipeline.sanitize_stem(original_name)
    suffix = Path(original_name).suffix.lower()
    if suffix not in config.SUPPORTED_EXTENSIONS:
        suffix = ".jpg"
    if suffix == ".jpeg":
        suffix = ".jpg"
    stamp = datetime.now(UTC).strftime("%Y%m%d_%H%M%S")
    short = uuid.uuid4().hex[:6]
    return f"{stamp}_{short}_{stem}{suffix}"