"""
Effects routes for L1 server.

Handles effect upload, listing, and metadata.
Effects are stored in IPFS like all other content-addressed data.
"""

import hashlib
import json
import logging
import time
from pathlib import Path
from typing import Optional

from fastapi import APIRouter, Request, Depends, HTTPException, UploadFile, File
from fastapi.responses import HTMLResponse, PlainTextResponse

from artdag_common import render
from artdag_common.middleware import wants_html, wants_json
from artdag_common.middleware.auth import UserContext

from ..dependencies import (
    require_auth, get_templates, get_redis_client,
    get_cache_manager,
)
from ..services.auth_service import AuthService
import ipfs_client

router = APIRouter()
logger = logging.getLogger(__name__)


def get_effects_dir() -> Path:
    """Get effects storage directory."""
    cache_mgr = get_cache_manager()
    effects_dir = Path(cache_mgr.cache_dir) / "_effects"
    effects_dir.mkdir(parents=True, exist_ok=True)
    return effects_dir


def parse_effect_metadata(source: str) -> dict:
    """
    Parse effect metadata from source code.

    Extracts PEP 723 dependencies and @-tag metadata from docstring.
    """
    import re

    metadata = {
        "name": "",
        "version": "1.0.0",
        "author": "",
        "temporal": False,
        "description": "",
        "params": [],
        "dependencies": [],
        "requires_python": ">=3.10",
    }

    # Parse PEP 723 dependencies
    pep723_match = re.search(r"# /// script\n(.*?)# ///", source, re.DOTALL)
    if pep723_match:
        block = pep723_match.group(1)
        deps_match = re.search(r'# dependencies = \[(.*?)\]', block, re.DOTALL)
        if deps_match:
            metadata["dependencies"] = re.findall(r'"([^"]+)"', deps_match.group(1))
        python_match = re.search(r'# requires-python = "([^"]+)"', block)
        if python_match:
            metadata["requires_python"] = python_match.group(1)

    # Parse docstring @-tags
    docstring_match = re.search(r'"""(.*?)"""', source, re.DOTALL)
    if not docstring_match:
        docstring_match = re.search(r"'''(.*?)'''", source, re.DOTALL)

    if docstring_match:
        docstring = docstring_match.group(1)
        lines = docstring.split("\n")

        current_param = None
        desc_lines = []
        in_description = False

        for line in lines:
            stripped = line.strip()

            if stripped.startswith("@effect "):
                metadata["name"] = stripped[8:].strip()
                in_description = False

            elif stripped.startswith("@version "):
                metadata["version"] = stripped[9:].strip()

            elif stripped.startswith("@author "):
                metadata["author"] = stripped[8:].strip()

            elif stripped.startswith("@temporal "):
                val = stripped[10:].strip().lower()
                metadata["temporal"] = val in ("true", "yes", "1")

            elif stripped.startswith("@description"):
                in_description = True
                desc_lines = []

            elif stripped.startswith("@param "):
                in_description = False
                if current_param:
                    metadata["params"].append(current_param)
                parts = stripped[7:].split()
                if len(parts) >= 2:
                    current_param = {
                        "name": parts[0],
                        "type": parts[1],
                        "description": "",
                    }
                else:
                    current_param = None

            elif stripped.startswith("@range ") and current_param:
                range_parts = stripped[7:].split()
                if len(range_parts) >= 2:
                    try:
                        current_param["range"] = [float(range_parts[0]), float(range_parts[1])]
                    except ValueError:
                        pass

            elif stripped.startswith("@default ") and current_param:
                current_param["default"] = stripped[9:].strip()

            elif stripped.startswith("@example"):
                in_description = False
                if current_param:
                    metadata["params"].append(current_param)
                    current_param = None

            elif in_description and stripped:
                desc_lines.append(stripped)

            elif current_param and stripped and not stripped.startswith("@"):
                current_param["description"] = stripped

        if in_description:
            metadata["description"] = " ".join(desc_lines)

        if current_param:
            metadata["params"].append(current_param)

    return metadata


@router.post("/upload")
async def upload_effect(
    file: UploadFile = File(...),
    ctx: UserContext = Depends(require_auth),
):
    """
    Upload an effect to IPFS.

    Parses PEP 723 metadata and @-tag docstring.
    Returns IPFS CID for use in recipes.
    """
    content = await file.read()

    try:
        source = content.decode("utf-8")
    except UnicodeDecodeError:
        raise HTTPException(400, "Effect must be valid UTF-8 text")

    # Parse metadata
    try:
        meta = parse_effect_metadata(source)
    except Exception as e:
        logger.warning(f"Failed to parse effect metadata: {e}")
        meta = {"name": file.filename or "unknown"}

    if not meta.get("name"):
        meta["name"] = Path(file.filename).stem if file.filename else "unknown"

    # Store effect source in IPFS
    cid = ipfs_client.add_bytes(content)
    if not cid:
        raise HTTPException(500, "Failed to store effect in IPFS")

    # Also keep local cache for fast worker access
    effects_dir = get_effects_dir()
    effect_dir = effects_dir / cid
    effect_dir.mkdir(parents=True, exist_ok=True)
    (effect_dir / "effect.py").write_text(source, encoding="utf-8")

    # Store metadata (locally and in IPFS)
    full_meta = {
        "cid": cid,
        "meta": meta,
        "uploader": ctx.actor_id,
        "uploaded_at": time.strftime("%Y-%m-%dT%H:%M:%SZ", time.gmtime()),
        "filename": file.filename,
    }
    (effect_dir / "metadata.json").write_text(json.dumps(full_meta, indent=2))

    # Also store metadata in IPFS for discoverability
    meta_cid = ipfs_client.add_json(full_meta)

    # Track ownership in item_types
    import database
    await database.save_item_metadata(
        cid=cid,
        actor_id=ctx.actor_id,
        item_type="effect",
        filename=file.filename,
    )

    # Assign friendly name
    from ..services.naming_service import get_naming_service
    naming = get_naming_service()
    friendly_entry = await naming.assign_name(
        cid=cid,
        actor_id=ctx.actor_id,
        item_type="effect",
        display_name=meta.get("name"),
        filename=file.filename,
    )

    logger.info(f"Uploaded effect '{meta.get('name')}' cid={cid} friendly_name='{friendly_entry['friendly_name']}' by {ctx.actor_id}")

    return {
        "cid": cid,
        "metadata_cid": meta_cid,
        "name": meta.get("name"),
        "friendly_name": friendly_entry["friendly_name"],
        "version": meta.get("version"),
        "temporal": meta.get("temporal", False),
        "params": meta.get("params", []),
        "dependencies": meta.get("dependencies", []),
        "uploaded": True,
    }


@router.get("/{cid}")
async def get_effect(
    cid: str,
    request: Request,
    ctx: UserContext = Depends(require_auth),
):
    """Get effect metadata by CID."""
    effects_dir = get_effects_dir()
    effect_dir = effects_dir / cid
    metadata_path = effect_dir / "metadata.json"

    # Try local cache first
    if metadata_path.exists():
        meta = json.loads(metadata_path.read_text())
    else:
        # Fetch from IPFS
        source_bytes = ipfs_client.get_bytes(cid)
        if not source_bytes:
            raise HTTPException(404, f"Effect {cid[:16]}... not found")

        # Cache locally
        effect_dir.mkdir(parents=True, exist_ok=True)
        source = source_bytes.decode("utf-8")
        (effect_dir / "effect.py").write_text(source)

        # Parse metadata from source
        parsed_meta = parse_effect_metadata(source)
        meta = {"cid": cid, "meta": parsed_meta}
        (effect_dir / "metadata.json").write_text(json.dumps(meta, indent=2))

    # Add friendly name if available
    from ..services.naming_service import get_naming_service
    naming = get_naming_service()
    friendly = await naming.get_by_cid(ctx.actor_id, cid)
    if friendly:
        meta["friendly_name"] = friendly["friendly_name"]
        meta["base_name"] = friendly["base_name"]
        meta["version_id"] = friendly["version_id"]

    if wants_json(request):
        return meta

    # HTML response
    from ..dependencies import get_nav_counts
    nav_counts = await get_nav_counts(ctx.actor_id)

    templates = get_templates(request)
    return render(templates, "effects/detail.html", request,
        effect=meta,
        user=ctx,
        nav_counts=nav_counts,
        active_tab="effects",
    )


@router.get("/{cid}/source")
async def get_effect_source(
    cid: str,
    ctx: UserContext = Depends(require_auth),
):
    """Get effect source code."""
    effects_dir = get_effects_dir()
    source_path = effects_dir / cid / "effect.py"

    # Try local cache first
    if source_path.exists():
        return PlainTextResponse(source_path.read_text())

    # Fetch from IPFS
    source_bytes = ipfs_client.get_bytes(cid)
    if not source_bytes:
        raise HTTPException(404, f"Effect {cid[:16]}... not found")

    # Cache locally
    source_path.parent.mkdir(parents=True, exist_ok=True)
    source = source_bytes.decode("utf-8")
    source_path.write_text(source)

    return PlainTextResponse(source)


@router.get("")
async def list_effects(
    request: Request,
    offset: int = 0,
    limit: int = 20,
    ctx: UserContext = Depends(require_auth),
):
    """List user's effects with pagination."""
    import database
    effects_dir = get_effects_dir()
    effects = []

    # Get user's effect CIDs from item_types
    user_items = await database.get_user_items(ctx.actor_id, item_type="effect", limit=1000)
    effect_cids = [item["cid"] for item in user_items]

    # Get naming service for friendly name lookup
    from ..services.naming_service import get_naming_service
    naming = get_naming_service()

    for cid in effect_cids:
        effect_dir = effects_dir / cid
        metadata_path = effect_dir / "metadata.json"
        if metadata_path.exists():
            try:
                meta = json.loads(metadata_path.read_text())
                # Add friendly name if available
                friendly = await naming.get_by_cid(ctx.actor_id, cid)
                if friendly:
                    meta["friendly_name"] = friendly["friendly_name"]
                    meta["base_name"] = friendly["base_name"]
                effects.append(meta)
            except json.JSONDecodeError:
                pass

    # Sort by upload time (newest first)
    effects.sort(key=lambda e: e.get("uploaded_at", ""), reverse=True)

    # Apply pagination
    total = len(effects)
    paginated_effects = effects[offset:offset + limit]
    has_more = offset + limit < total

    if wants_json(request):
        return {"effects": paginated_effects, "offset": offset, "limit": limit, "has_more": has_more}

    from ..dependencies import get_nav_counts
    nav_counts = await get_nav_counts(ctx.actor_id)

    templates = get_templates(request)
    return render(templates, "effects/list.html", request,
        effects=paginated_effects,
        user=ctx,
        nav_counts=nav_counts,
        active_tab="effects",
        offset=offset,
        limit=limit,
        has_more=has_more,
    )


@router.post("/{cid}/publish")
async def publish_effect(
    cid: str,
    request: Request,
    ctx: UserContext = Depends(require_auth),
):
    """Publish effect to L2 ActivityPub server."""
    from ..services.cache_service import CacheService
    import database

    # Verify effect exists
    effects_dir = get_effects_dir()
    effect_dir = effects_dir / cid
    if not effect_dir.exists():
        error = "Effect not found"
        if wants_html(request):
            return HTMLResponse(f'<span class="text-red-400">{error}</span>')
        raise HTTPException(404, error)

    # Use cache service to publish
    cache_service = CacheService(database, get_cache_manager())
    ipfs_cid, error = await cache_service.publish_to_l2(
        cid=cid,
        actor_id=ctx.actor_id,
        l2_server=ctx.l2_server,
        auth_token=request.cookies.get("auth_token"),
    )

    if error:
        if wants_html(request):
            return HTMLResponse(f'<span class="text-red-400">{error}</span>')
        raise HTTPException(400, error)

    logger.info(f"Published effect {cid[:16]}... to L2 by {ctx.actor_id}")

    if wants_html(request):
        return HTMLResponse(f'<span class="text-green-400">Shared: {ipfs_cid[:16]}...</span>')

    return {"ipfs_cid": ipfs_cid, "cid": cid, "published": True}


@router.delete("/{cid}")
async def delete_effect(
    cid: str,
    ctx: UserContext = Depends(require_auth),
):
    """Remove user's ownership link to an effect."""
    import database

    # Remove user's ownership link from item_types
    await database.delete_item_type(cid, ctx.actor_id, "effect")

    # Remove friendly name
    await database.delete_friendly_name(ctx.actor_id, cid)

    # Check if anyone still owns this effect
    remaining_owners = await database.get_item_types(cid)

    # Only delete local files if no one owns it anymore
    if not remaining_owners:
        effects_dir = get_effects_dir()
        effect_dir = effects_dir / cid
        if effect_dir.exists():
            import shutil
            shutil.rmtree(effect_dir)

        # Unpin from IPFS
        ipfs_client.unpin(cid)
        logger.info(f"Garbage collected effect {cid[:16]}... (no remaining owners)")

    logger.info(f"Removed effect {cid[:16]}... ownership for {ctx.actor_id}")
    return {"deleted": True}