from __future__ import annotations

import json
import re
from dataclasses import asdict, dataclass
from datetime import datetime, timezone
from pathlib import Path
from typing import Any
from uuid import uuid4


def _now() -> str:
    return datetime.now(timezone.utc).isoformat()


def _normal(value: str) -> str:
    return re.sub(r"[^a-z0-9]+", " ", value.casefold()).strip()


def _friendly_name(value: str, fallback: str) -> str:
    text = str(value or "").strip()
    if not text:
        return fallback
    if re.search(r"^[A-Za-z]:[\\/]", text) or "/" in text or "\\" in text:
        return Path(text).name or fallback
    return text


def _is_lora_training_checkpoint(path: Path) -> bool:
    """Return whether a LoRA weight is an intermediate training snapshot.

    The LoRA trainer writes both the finished adapter and periodic weights such
    as ``name_epoch_0050.safetensors``.  The latter are useful for recovery,
    but are not independently selectable models in ADAM's model library.
    """
    name = path.stem.casefold()
    return bool(re.search(
        r"(?:^|[_\- ])(?:checkpoint(?:[_\- ]?(?:epoch|e|step))?|epoch|e|step)[_\- ]?\d+(?:[_\- ]|$)",
        name,
    ))


@dataclass(slots=True)
class Asset:
    id: str
    kind: str
    name: str
    path: str
    trainer: str = ""
    dataset_id: str = ""
    checkpoint: str = ""
    epochs: int = 0
    created_at: str = ""
    metadata: dict[str, Any] | None = None

    @classmethod
    def from_dict(cls, payload: dict[str, Any]) -> "Asset":
        return cls(
            id=str(payload.get("id") or uuid4().hex[:12]),
            kind=str(payload.get("kind", "")),
            name=str(payload.get("name", "")),
            path=str(payload.get("path", "")),
            trainer=str(payload.get("trainer", "")),
            dataset_id=str(payload.get("dataset_id", "")),
            checkpoint=str(payload.get("checkpoint", "")),
            epochs=int(payload.get("epochs", 0) or 0),
            created_at=str(payload.get("created_at") or _now()),
            metadata=dict(payload.get("metadata") or {}),
        )


class AssetRegistry:
    """Persistent friendly-name index for datasets, models, and checkpoints."""

    def __init__(self, root: Path) -> None:
        self.path = root.resolve() / "data" / "assets.json"
        self.assets: list[Asset] = []
        self.load()

    def load(self) -> None:
        try:
            payload = json.loads(self.path.read_text(encoding="utf-8"))
            self.assets = [
                Asset.from_dict(item)
                for item in payload.get("assets", [])
                if isinstance(item, dict)
            ]
        except (OSError, ValueError, TypeError, json.JSONDecodeError):
            self.assets = []

    def save(self) -> None:
        self.path.parent.mkdir(parents=True, exist_ok=True)
        temporary = self.path.with_suffix(".tmp")
        temporary.write_text(
            json.dumps({"assets": [asdict(item) for item in self.assets]}, indent=2),
            encoding="utf-8",
        )
        temporary.replace(self.path)

    def register(
        self,
        *,
        kind: str,
        name: str,
        path: str,
        trainer: str = "",
        dataset_id: str = "",
        checkpoint: str = "",
        epochs: int = 0,
        metadata: dict[str, Any] | None = None,
        persist: bool = True,
    ) -> Asset:
        resolved = str(Path(path).expanduser().resolve())
        existing = next(
            (
                item
                for item in self.assets
                if item.kind == kind and Path(item.path) == Path(resolved)
            ),
            None,
        )
        asset = existing or Asset(uuid4().hex[:12], kind, name, resolved)
        asset.name = name.strip() or Path(resolved).name
        asset.trainer = trainer
        asset.dataset_id = dataset_id
        asset.checkpoint = checkpoint
        asset.epochs = int(epochs)
        asset.created_at = asset.created_at or _now()
        if metadata:
            current = dict(asset.metadata or {})
            current.update(metadata)
            asset.metadata = current
        if existing is None:
            self.assets.insert(0, asset)
        if persist:
            self.save()
        return asset

    def ingest_result(self, result: dict[str, Any]) -> None:
        entries = result.get("assets", [])
        if not isinstance(entries, list):
            return
        for item in entries:
            if not isinstance(item, dict):
                continue
            if item.get("kind") and item.get("path"):
                values = {
                    key: item[key]
                    for key in (
                        "kind", "name", "path", "trainer", "dataset_id",
                        "checkpoint", "epochs", "metadata",
                    )
                    if key in item
                }
                if "trigger_word" in item:
                    metadata = dict(values.get("metadata") or {})
                    metadata["trigger_word"] = str(item.get("trigger_word") or "")
                    values["metadata"] = metadata
                dataset_path = str(item.get("dataset_path", ""))
                if item.get("kind") == "model" and dataset_path and Path(dataset_path).is_dir():
                    dataset = self.register(
                        kind="dataset",
                        name=Path(dataset_path).name,
                        path=dataset_path,
                    )
                    values["dataset_id"] = dataset.id
                values.setdefault("name", Path(str(item["path"])).name)
                self.register(**values)

    def find(self, kind: str, query: str, *, trainer: str = "") -> list[Asset]:
        wanted = _normal(query)
        matches = []
        exact = []
        for item in self.assets:
            if item.kind != kind or (trainer and item.trainer != trainer):
                continue
            haystacks = {_normal(item.name), _normal(Path(item.path).name)}
            if wanted in haystacks:
                exact.append(item)
            elif any(wanted and wanted in value for value in haystacks):
                matches.append(item)
        return exact or matches

    def discover(self, config: Any, *, persist: bool = True) -> None:
        # Models are stored by their output folder (or the model file itself).
        # Keep the registry in step with the filesystem so removing an old
        # output cannot leave a ghost model that makes name matching ambiguous.
        self.assets = [
            item
            for item in self.assets
            if item.kind != "model" or (
                item.path.strip() and Path(item.path).expanduser().exists()
            )
            # Old ADAM versions registered LoRA epoch snapshots.  Prune those
            # stale records as well as skipping them during new discovery.
            and not (
                item.trainer == "lora"
                and _is_lora_training_checkpoint(Path(item.path))
            )
        ]
        folders = config.get("tool_folders", {})
        if not isinstance(folders, dict):
            return
        folders = dict(folders)
        app_root = self.path.parent.parent
        from adam.video_lora import discover_assets as discover_video_assets
        discover_video_assets(self, app_root, config)
        if not folders.get("oasis_trainer"):
            try:
                external = json.loads((app_root / "config" / "external_tools.json").read_text(encoding="utf-8"))
            except (OSError, ValueError, TypeError, json.JSONDecodeError):
                external = {}
            for entry in external.get("tools", []) if isinstance(external, dict) else []:
                if isinstance(entry, dict) and entry.get("id") == "external_oasis_game_trainer":
                    root = str(entry.get("backend", {}).get("root", ""))
                    if root:
                        folders["oasis_trainer"] = root
        external_lora_root = app_root / "LoRAModelsHere"
        if external_lora_root.is_dir():
            for path in external_lora_root.rglob("*.safetensors"):
                if (
                    path.is_file()
                    and "_comfy" not in path.stem.casefold()
                    and not _is_lora_training_checkpoint(path)
                ):
                    self.register(
                        kind="model",
                        name=path.stem.removesuffix("_cancelled"),
                        path=str(path),
                        trainer="lora",
                        checkpoint=str(path),
                        persist=False,
                    )
        base_model_root = app_root / "LoRA StableDiffusionModels Here"
        if base_model_root.is_dir():
            for path in base_model_root.iterdir():
                is_model_file = path.is_file() and path.suffix.casefold() in {
                    ".safetensors", ".ckpt", ".pt", ".bin"
                }
                is_diffusers_folder = path.is_dir() and (
                    (path / "model_index.json").is_file()
                    or (path / "unet" / "config.json").is_file()
                )
                if is_model_file or is_diffusers_folder:
                    self.register(
                        kind="base_model",
                        name=path.stem if path.is_file() else path.name,
                        path=str(path),
                        trainer="stable_diffusion",
                        persist=False,
                    )
        flow_datasets = self._flow_dataset_paths()
        collector = Path(str(folders.get("dataset_collector", ""))) / "Datasets"
        if collector.is_dir():
            for folder in collector.iterdir():
                if folder.is_dir():
                    self.register(
                        kind="dataset", name=folder.name, path=str(folder), persist=False
                    )
        for trainer, folder_name, output_name in (
            ("ddpm", "ddpm_trainer", "output"),
            ("lora", "lora_trainer", "output"),
            ("flow", "flow_trainer", "output_flow_models"),
            ("oasis", "oasis_trainer", "output_action_flow_models"),
        ):
            root = Path(str(folders.get(folder_name, ""))) / output_name
            if not root.is_dir():
                continue
            # LoRA Trainer versions do not all agree on their output layout.
            # Some write ``output/<run>/<name>.safetensors`` while others add
            # a second folder below the run.  Register the actual weight file
            # in either layout so the generator can load it directly.
            if trainer == "lora":
                for checkpoint_path in root.rglob("*.safetensors"):
                    if (
                        not checkpoint_path.is_file()
                        or "_comfy" in checkpoint_path.stem.casefold()
                        or _is_lora_training_checkpoint(checkpoint_path)
                    ):
                        continue
                    trigger_word = ""
                    for metadata_path in (checkpoint_path.parent / "model_info.json", checkpoint_path.parent.parent / "model_info.json"):
                        try:
                            metadata = json.loads(metadata_path.read_text(encoding="utf-8"))
                            trigger_word = str(metadata.get("trigger_word") or "")
                            if trigger_word:
                                break
                        except (OSError, ValueError, TypeError, json.JSONDecodeError):
                            continue
                    self.register(
                        kind="model",
                        name=checkpoint_path.stem.removesuffix("_cancelled"),
                        path=str(checkpoint_path),
                        trainer="lora",
                        checkpoint=str(checkpoint_path),
                        metadata={"trigger_word": trigger_word or checkpoint_path.stem.removesuffix("_cancelled")},
                        persist=False,
                    )
                continue
            for folder in root.iterdir():
                if not folder.is_dir():
                    continue
                name = folder.name
                dataset_path = ""
                if trainer == "ddpm":
                    # DDPM writes a durable sidecar with the friendly model name and
                    # source dataset. Prefer it over a filesystem-safe folder name.
                    try:
                        metadata = json.loads((folder / "model_info.json").read_text(encoding="utf-8"))
                        name = str(metadata.get("model_name") or metadata.get("name") or name)
                        dataset_path = str(metadata.get("dataset_dir") or "")
                    except (OSError, ValueError, TypeError, json.JSONDecodeError):
                        pass
                    checkpoints = sorted(
                        folder.glob("checkpoint-*"),
                        key=lambda p: int(p.name.rsplit("-", 1)[-1])
                        if p.name.rsplit("-", 1)[-1].isdigit()
                        else -1,
                    )
                elif trainer == "flow":
                    checkpoints = []
                    try:
                        metadata = json.loads(
                            (folder / "flow_model_info.json").read_text(encoding="utf-8")
                        )
                        if metadata.get("model_type") != "rectified_flow":
                            continue
                        if not (folder / "unet" / "config.json").is_file():
                            continue
                        name = str(metadata.get("model_name") or metadata.get("name") or name)
                        dataset_path = flow_datasets.get(str(folder.resolve()), "")
                    except (OSError, ValueError, TypeError, json.JSONDecodeError):
                        continue
                else:
                    checkpoints = []
                    try:
                        metadata = json.loads(
                            (folder / "action_flow_model_info.json").read_text(encoding="utf-8")
                        )
                        if metadata.get("model_type") != "action_conditioned_rectified_flow_video":
                            continue
                        if not (folder / "unet" / "config.json").is_file():
                            continue
                        name = _friendly_name(
                            str(metadata.get("model_name") or metadata.get("name") or name),
                            folder.name,
                        )
                    except (OSError, ValueError, TypeError, json.JSONDecodeError):
                        continue
                checkpoint = (
                    str(folder) if trainer in {"flow", "oasis"} else str(checkpoints[-1]) if checkpoints else ""
                )
                dataset_id = ""
                if dataset_path and Path(dataset_path).is_dir():
                    dataset_asset = self.register(
                        kind="dataset",
                        name=Path(dataset_path).name,
                        path=dataset_path,
                        persist=False,
                    )
                    dataset_id = dataset_asset.id
                self.register(
                    kind="model",
                    name=name,
                    path=str(folder),
                    trainer=trainer,
                    dataset_id=dataset_id,
                    checkpoint=checkpoint,
                    metadata=({"trigger_word": trigger_word or name} if trainer == "lora" else None),
                    persist=False,
                )
        try:
            from adam.dataset_registry import DatasetRegistry

            dataset_registry = DatasetRegistry(app_root, config)
            valid_location_ids = {location.id for location in dataset_registry.known_locations()}
            self.assets = [
                item for item in self.assets
                if not (
                    item.kind == "dataset"
                    and isinstance(item.metadata, dict)
                    and item.metadata.get("dataset_registry_source") in {"adam", "tool"}
                    and item.metadata.get("dataset_location_id")
                    and item.metadata.get("dataset_location_id") not in valid_location_ids
                )
            ]
            dataset_registry.discover_into_assets(self, persist=False, update_cache=persist)
        except Exception:
            pass
        if persist:
            self.save()

    def _flow_dataset_paths(self) -> dict[str, str]:
        """Recover source datasets for Flow models created by ADAM in older runs."""
        jobs_path = self.path.parent / "jobs.json"
        try:
            payload = json.loads(jobs_path.read_text(encoding="utf-8"))
            jobs = payload.get("jobs", [])
        except (OSError, ValueError, TypeError, json.JSONDecodeError):
            return {}
        links: dict[str, str] = {}
        if not isinstance(jobs, list):
            return links
        for job in jobs:
            if not isinstance(job, dict):
                continue
            plan = job.get("plan", {})
            steps = plan.get("steps", []) if isinstance(plan, dict) else []
            if not isinstance(steps, list):
                continue
            for step in steps:
                if not isinstance(step, dict) or step.get("tool_id") != "flow_trainer":
                    continue
                arguments = step.get("arguments", {})
                if not isinstance(arguments, dict):
                    continue
                output = str(arguments.get("output_dir", ""))
                dataset = str(arguments.get("dataset_dir", ""))
                if not output or not dataset or not Path(dataset).is_dir():
                    continue
                try:
                    links[str(Path(output).expanduser().resolve())] = str(Path(dataset).expanduser().resolve())
                except OSError:
                    continue
        return links