"""
title: NOMYO Router - an Ollama Proxy with Endpoint:Model aware routing
author: alpha-nerd-nomyo
author_url: https://github.com/nomyo-ai
version: 0.3
license: AGPL
"""
# -------------------------------------------------------------
import json, time, asyncio, yaml, ollama, openai, os, re, aiohttp, ssl
from pathlib import Path
from typing import Dict, Set, List, Optional
from fastapi import FastAPI, Request, HTTPException
from fastapi_sse import sse_handler
from fastapi.staticfiles import StaticFiles
from fastapi.middleware.cors import CORSMiddleware
from starlette.responses import StreamingResponse, JSONResponse, Response, HTMLResponse, RedirectResponse
from pydantic import Field
from pydantic_settings import BaseSettings
from collections import defaultdict

# ------------------------------------------------------------------
# In‑memory caches
# ------------------------------------------------------------------
# Successful results are cached for 300s
_models_cache: dict[str, tuple[Set[str], float]] = {}
# Transient errors are cached for 1s – the key stays until the
# timeout expires, after which the endpoint will be queried again.
_error_cache: dict[str, float] = {}

# ------------------------------------------------------------------
# SSE Queues
# ------------------------------------------------------------------
_subscribers: Set[asyncio.Queue] = set()
_subscribers_lock = asyncio.Lock()

# ------------------------------------------------------------------
# aiohttp Global Sessions
# ------------------------------------------------------------------
app_state = {
    "session": None,
    "connector": None,
}

# -------------------------------------------------------------
# 1. Configuration loader
# -------------------------------------------------------------
class Config(BaseSettings):
    # List of Ollama endpoints
    endpoints: list[str] = Field(
        default_factory=lambda: [
            "http://localhost:11434",
        ]
    )
    # Max concurrent connections per endpoint‑model pair, see OLLAMA_NUM_PARALLEL
    max_concurrent_connections: int = 1

    api_keys: Dict[str, str] = Field(default_factory=dict)

    class Config:
        # Load from `config.yaml` first, then from env variables
        env_prefix = "NOMYO_ROUTER_"
        yaml_file = Path("config.yaml")  # relative to cwd

    @classmethod
    def _expand_env_refs(cls, obj):
        """Recursively replace `${VAR}` with os.getenv('VAR')."""
        if isinstance(obj, dict):
            return {k: cls._expand_env_refs(v) for k, v in obj.items()}
        if isinstance(obj, list):
            return [cls._expand_env_refs(v) for v in obj]
        if isinstance(obj, str):
            # Only expand if it is exactly ${VAR}
            m = re.fullmatch(r"\$\{([A-Za-z_][A-Za-z0-9_]*)\}", obj)
            if m:
                return os.getenv(m.group(1), "")
        return obj

    @classmethod
    def from_yaml(cls, path: Path) -> "Config":
        """Load the YAML file and create the Config instance."""
        if path.exists():
            with path.open("r", encoding="utf-8") as fp:
                data = yaml.safe_load(fp) or {}
                cleaned = cls._expand_env_refs(data)
            return cls(**cleaned)
        return cls()

# Create the global config object – it will be overwritten on startup
config = Config()

# -------------------------------------------------------------
# 2. FastAPI application
# -------------------------------------------------------------
app = FastAPI()
sse_handler.app = app
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["GET", "POST", "DELETE"],
    allow_headers=["Authorization", "Content-Type"],
)
# -------------------------------------------------------------
# 3. Global state: per‑endpoint per‑model active connection counters
# -------------------------------------------------------------
usage_counts: Dict[str, Dict[str, int]] = defaultdict(lambda: defaultdict(int))
usage_lock = asyncio.Lock()  # protects access to usage_counts

# -------------------------------------------------------------
# 4. Helperfunctions 
# -------------------------------------------------------------
aiotimeout = aiohttp.ClientTimeout(total=5)

def _is_fresh(cached_at: float, ttl: int) -> bool:
    return (time.time() - cached_at) < ttl

async def _ensure_success(resp: aiohttp.ClientResponse) -> None:
    if resp.status >= 400:
        text = await resp.text()
        raise HTTPException(status_code=resp.status, detail=text)

async def fetch_available_models(endpoint: str, api_key: Optional[str] = None) -> Set[str]:
    """
    Query <endpoint>/api/tags and return a set of all model names that the
    endpoint *advertises* (i.e. is capable of serving).  This endpoint lists
    every model that is installed on the Ollama instance, regardless of
    whether the model is currently loaded into memory.

    If the request fails (e.g. timeout, 5xx, or malformed response), an empty
    set is returned.
    """
    headers = None
    if api_key is not None:
        headers = {"Authorization": "Bearer " + api_key}

    if endpoint in _models_cache:
        models, cached_at = _models_cache[endpoint]
        if _is_fresh(cached_at, 300):
            return models
        else:
            # stale entry – drop it
            del _models_cache[endpoint]

    if endpoint in _error_cache:
        if _is_fresh(_error_cache[endpoint], 1):
            # Still within the short error TTL – pretend nothing is available
            return set()
        else:
            # Error expired – remove it
            del _error_cache[endpoint]

    if "/v1" in endpoint:
        endpoint_url = f"{endpoint}/models"
        key = "data"
    else:
        endpoint_url = f"{endpoint}/api/tags"
        key = "models"
    client: aiohttp.ClientSession = app_state["session"]
    try:
        async with client.get(endpoint_url, headers=headers) as resp:
            await _ensure_success(resp)
            data = await resp.json()

            items = data.get(key, [])
            models = {item.get("id") or item.get("name") for item in items if item.get("id") or item.get("name")}
            
            if models:
                _models_cache[endpoint] = (models, time.time())
                return models
            else:
                # Empty list – treat as “no models”, but still cache for 300s
                _models_cache[endpoint] = (models, time.time())
                return models
    except Exception as e:
        # Treat any error as if the endpoint offers no models
        print(f"[fetch_available_models] {endpoint} error: {e}")
        _error_cache[endpoint] = time.time()
        return set()


async def fetch_loaded_models(endpoint: str) -> Set[str]:
    """
    Query <endpoint>/api/ps and return a set of model names that are currently
    loaded on that endpoint. If the request fails (e.g. timeout, 5xx), an empty
    set is returned.
    """
    client: aiohttp.ClientSession = app_state["session"]
    try:
        async with client.get(f"{endpoint}/api/ps") as resp:
            await _ensure_success(resp)
            data = await resp.json()
        # The response format is:
        #   {"models": [{"name": "model1"}, {"name": "model2"}]}
        models = {m.get("name") for m in data.get("models", []) if m.get("name")}
        return models
    except Exception:
        # If anything goes wrong we simply assume the endpoint has no models
        return set()

async def fetch_endpoint_details(endpoint: str, route: str, detail: str, api_key: Optional[str] = None) -> List[dict]:
    """
    Query <endpoint>/<route> to fetch <detail> and return a List of dicts with details
    for the corresponding Ollama endpoint. If the request fails we respond with "N/A" for detail.
    """
    client: aiohttp.ClientSession = app_state["session"]
    headers = None
    if api_key is not None:
        headers = {"Authorization": "Bearer " + api_key}
    
    try:
        async with client.get(f"{endpoint}{route}", headers=headers) as resp:
            await _ensure_success(resp)
            data = await resp.json()
        detail = data.get(detail, [])
        return detail
    except Exception as e:
        # If anything goes wrong we cannot reply details
        print(e)
        return []

def ep2base(ep):
    if "/v1" in ep:
        base_url = ep
    else:
        base_url = ep+"/v1"
    return base_url

def dedupe_on_keys(dicts, key_fields):
    """
    Helper function to deduplicate endpoint details based on given dict keys.
    """
    seen = set()
    out = []
    for d in dicts:
        # Build a tuple of the values for the chosen keys
        key = tuple(d.get(k) for k in key_fields)
        if key not in seen:
            seen.add(key)
            out.append(d)
    return out

async def increment_usage(endpoint: str, model: str) -> None:
    async with usage_lock:
        usage_counts[endpoint][model] += 1
    await publish_snapshot()

async def decrement_usage(endpoint: str, model: str) -> None:
    async with usage_lock:
        # Avoid negative counts
        current = usage_counts[endpoint].get(model, 0)
        if current > 0:
            usage_counts[endpoint][model] = current - 1
        # Optionally, clean up zero entries
        if usage_counts[endpoint].get(model, 0) == 0:
            usage_counts[endpoint].pop(model, None)
        #if not usage_counts[endpoint]:
        #    usage_counts.pop(endpoint, None)
    await publish_snapshot()

# ------------------------------------------------------------------
# SSE Helpser
# ------------------------------------------------------------------
async def publish_snapshot():
    snapshot = json.dumps({"usage_counts": usage_counts})
    async with _subscribers_lock:
        for q in _subscribers:
            # If the queue is full, drop the message to avoid back‑pressure.
            if q.full():
                continue
            await q.put(snapshot)

# ------------------------------------------------------------------
# Subscriber helpers
# ------------------------------------------------------------------
async def subscribe() -> asyncio.Queue:
    """
    Returns a new Queue that will receive every snapshot.
    """
    q: asyncio.Queue = asyncio.Queue(maxsize=10)
    async with _subscribers_lock:
        _subscribers.add(q)
    return q

async def unsubscribe(q: asyncio.Queue):
    async with _subscribers_lock:
        _subscribers.discard(q)

# ------------------------------------------------------------------
# Convenience wrapper – returns the current snapshot (for the proxy)
# ------------------------------------------------------------------
async def get_usage_counts() -> Dict:
    return dict(usage_counts)   # shallow copy

# -------------------------------------------------------------
# 5. Endpoint selection logic (respecting the configurable limit)
# -------------------------------------------------------------
async def choose_endpoint(model: str) -> str:
    """
    Determine which endpoint to use for the given model while respecting
    the `max_concurrent_connections` per endpoint‑model pair **and**
    ensuring that the chosen endpoint actually *advertises* the model.

    The selection algorithm:

    1️⃣  Query every endpoint for its advertised models (`/api/tags`).
    2️⃣  Build a list of endpoints that contain the requested model.
    3️⃣  For those endpoints, find those that have the model loaded
         (`/api/ps`) *and* still have a free slot.
    4️⃣  If none are both loaded and free, fall back to any endpoint
         from the filtered list that simply has a free slot.
    5️⃣  If all are saturated, pick any endpoint from the filtered list
         (the request will queue on that endpoint).
    6️⃣  If no endpoint advertises the model at all, raise an error.
    """
    # 1️⃣  Gather advertised‑model sets for all endpoints concurrently
    tag_tasks = [fetch_available_models(ep) for ep in config.endpoints if "/v1" not in ep]
    tag_tasks += [fetch_available_models(ep, config.api_keys[ep]) for ep in config.endpoints if "/v1" in ep]
    advertised_sets = await asyncio.gather(*tag_tasks)

    # 2️⃣  Filter endpoints that advertise the requested model
    candidate_endpoints = [
        ep for ep, models in zip(config.endpoints, advertised_sets)
        if model in models
    ]
    
    # 6️⃣ 
    if not candidate_endpoints:
        raise RuntimeError(
            f"None of the configured endpoints ({', '.join(config.endpoints)}) "
            f"advertise the model '{model}'."
        )

    # 3️⃣  Among the candidates, find those that have the model *loaded*
    #      (concurrently, but only for the filtered list)
    load_tasks = [fetch_loaded_models(ep) for ep in candidate_endpoints]
    loaded_sets = await asyncio.gather(*load_tasks)
    
    async with usage_lock:
        # Helper: get current usage count for (endpoint, model)
        def current_usage(ep: str) -> int:
            return usage_counts.get(ep, {}).get(model, 0)
        
        # 3️⃣ Endpoints that have the model loaded *and* a free slot
        loaded_and_free = [
            ep for ep, models in zip(candidate_endpoints, loaded_sets)
            if model in models and usage_counts.get(ep, {}).get(model, 0) < config.max_concurrent_connections
        ]
        
        if loaded_and_free:
            ep = min(loaded_and_free, key=current_usage)
            return ep

        # 4️⃣ Endpoints among the candidates that simply have a free slot
        endpoints_with_free_slot = [
            ep for ep in candidate_endpoints
            if usage_counts.get(ep, {}).get(model, 0) < config.max_concurrent_connections
        ]

        if endpoints_with_free_slot:
            ep = min(endpoints_with_free_slot, key=current_usage)
            return ep

        # 5️⃣ All candidate endpoints are saturated – pick one with lowest usages count (will queue)
        ep = min(candidate_endpoints, key=current_usage)
        return ep

# -------------------------------------------------------------
# 6. API route – Generate
# -------------------------------------------------------------
@app.post("/api/generate")
async def proxy(request: Request):
    """
    Proxy a generate request to Ollama and stream the response back to the client.
    """
    # 1. Parse and validate request
    try:
        body_bytes = await request.body()
        payload = json.loads(body_bytes.decode("utf-8"))
        
        model = payload.get("model")
        prompt = payload.get("prompt")
        suffix = payload.get("suffix")
        system = payload.get("system")
        template = payload.get("template")
        context = payload.get("context")
        stream = payload.get("stream")
        think = payload.get("think")
        raw = payload.get("raw")
        format = payload.get("format")
        images = payload.get("images")
        options = payload.get("options")
        keep_alive = payload.get("keep_alive")

        if not model:
            raise HTTPException(
                status_code=400, detail="Missing required field 'model'"
            )
        if not prompt:
            raise HTTPException(
                status_code=400, detail="Missing required field 'prompt'"
            )
    except json.JSONDecodeError as e:
        raise HTTPException(status_code=400, detail=f"Invalid JSON: {e}") from e

    # 2. Decide which endpoint to use
    endpoint = await choose_endpoint(model)

    # Increment usage counter for this endpoint‑model pair
    await increment_usage(endpoint, model)

    # 3. Create Ollama client instance
    client = ollama.AsyncClient(host=endpoint)

    # 4. Async generator that streams data and decrements the counter
    async def stream_generate_response():
        try:
            async_gen = await client.generate(model=model, prompt=prompt, suffix=suffix, system=system, template=template, context=context, stream=stream, think=think, raw=raw, format=format, images=images, options=options, keep_alive=keep_alive)
            if stream == True:
                async for chunk in async_gen:
                    if hasattr(chunk, "model_dump_json"):
                        json_line = chunk.model_dump_json()
                    else:
                        json_line = json.dumps(chunk)
                    yield json_line.encode("utf-8") + b"\n"
            else:
                json_line = (
                    async_gen.model_dump_json()
                    if hasattr(async_gen, "model_dump_json")
                    else json.dumps(async_gen)
                )
                yield json_line.encode("utf-8") + b"\n"

        finally:
            # Ensure counter is decremented even if an exception occurs
            await decrement_usage(endpoint, model)

    # 5. Return a StreamingResponse backed by the generator
    return StreamingResponse(
        stream_generate_response(),
        media_type="application/json",
    )

# -------------------------------------------------------------
# 7. API route – Chat
# -------------------------------------------------------------
@app.post("/api/chat")
async def chat_proxy(request: Request):
    """
    Proxy a chat request to Ollama and stream the endpoint reply.
    """
    # 1. Parse and validate request
    try:
        body_bytes = await request.body()
        payload = json.loads(body_bytes.decode("utf-8"))

        model = payload.get("model")
        messages = payload.get("messages")
        tools = payload.get("tools")
        stream = payload.get("stream")
        think = payload.get("think")
        format = payload.get("format")
        options = payload.get("options")
        keep_alive = payload.get("keep_alive")

        if not model:
            raise HTTPException(
                status_code=400, detail="Missing required field 'model'"
            )
        if not isinstance(messages, list):
            raise HTTPException(
                status_code=400, detail="Missing or invalid 'message' field (must be a list)"
            )
    except json.JSONDecodeError as e:
        raise HTTPException(status_code=400, detail=f"Invalid JSON: {e}") from e

    # 2. Endpoint logic
    endpoint = await choose_endpoint(model)
    await increment_usage(endpoint, model)
    client = ollama.AsyncClient(host=endpoint)

    # 3. Async generator that streams chat data and decrements the counter
    async def stream_chat_response():
        try:
            # The chat method returns a generator of dicts (or GenerateResponse)
            async_gen = await client.chat(model=model, messages=messages, tools=tools, stream=stream, think=think, format=format, options=options, keep_alive=keep_alive)
            if stream == True:
                async for chunk in async_gen:
                    # `chunk` can be a dict or a pydantic model – dump to JSON safely
                    if hasattr(chunk, "model_dump_json"):
                        json_line = chunk.model_dump_json()
                    else:
                        json_line = json.dumps(chunk)
                    yield json_line.encode("utf-8") + b"\n"
            else:
                json_line = (
                    async_gen.model_dump_json()
                    if hasattr(async_gen, "model_dump_json")
                    else json.dumps(async_gen)
                )
                yield json_line.encode("utf-8") + b"\n"

        finally:
            # Ensure counter is decremented even if an exception occurs
            await decrement_usage(endpoint, model)

    # 4. Return a StreamingResponse backed by the generator
    return StreamingResponse(
        stream_chat_response(),
        media_type="application/json",
    )

# -------------------------------------------------------------
# 8. API route – Embedding - deprecated
# -------------------------------------------------------------
@app.post("/api/embeddings")
async def embedding_proxy(request: Request):
    """
    Proxy an embedding request to Ollama and reply with embeddings.

    """
    # 1. Parse and validate request
    try:
        body_bytes = await request.body()
        payload = json.loads(body_bytes.decode("utf-8"))

        model = payload.get("model")
        prompt = payload.get("prompt")
        options = payload.get("options")
        keep_alive = payload.get("keep_alive")

        if not model:
            raise HTTPException(
                status_code=400, detail="Missing required field 'model'"
            )
        if not prompt:
            raise HTTPException(
                status_code=400, detail="Missing required field 'prompt'"
            )
    except json.JSONDecodeError as e:
        raise HTTPException(status_code=400, detail=f"Invalid JSON: {e}") from e

    # 2. Endpoint logic
    endpoint = await choose_endpoint(model)
    await increment_usage(endpoint, model)
    client = ollama.AsyncClient(host=endpoint)

    # 3. Async generator that streams embedding data and decrements the counter
    async def stream_embedding_response():
        try:
            # The chat method returns a generator of dicts (or GenerateResponse)
            async_gen = await client.embeddings(model=model, prompt=prompt, options=options, keep_alive=keep_alive)
            if hasattr(async_gen, "model_dump_json"):
                json_line = async_gen.model_dump_json()
            else:
                json_line = json.dumps(async_gen)
            yield json_line.encode("utf-8") + b"\n"
        finally:
            # Ensure counter is decremented even if an exception occurs
            await decrement_usage(endpoint, model)

    # 5. Return a StreamingResponse backed by the generator
    return StreamingResponse(
        stream_embedding_response(),
        media_type="application/json",
    )

# -------------------------------------------------------------
# 9. API route – Embed
# -------------------------------------------------------------
@app.post("/api/embed")
async def embed_proxy(request: Request):
    """
    Proxy an embed request to Ollama and reply with embeddings.

    """
    # 1. Parse and validate request
    try:
        body_bytes = await request.body()
        payload = json.loads(body_bytes.decode("utf-8"))

        model = payload.get("model")
        input = payload.get("input")
        truncate = payload.get("truncate")
        options = payload.get("options")
        keep_alive = payload.get("keep_alive")

        if not model:
            raise HTTPException(
                status_code=400, detail="Missing required field 'model'"
            )
        if not input:
            raise HTTPException(
                status_code=400, detail="Missing required field 'input'"
            )
    except json.JSONDecodeError as e:
        raise HTTPException(status_code=400, detail=f"Invalid JSON: {e}") from e

    # 2. Endpoint logic
    endpoint = await choose_endpoint(model)
    await increment_usage(endpoint, model)
    client = ollama.AsyncClient(host=endpoint)

    # 3. Async generator that streams embed data and decrements the counter
    async def stream_embedding_response():
        try:
            # The chat method returns a generator of dicts (or GenerateResponse)
            async_gen = await client.embed(model=model, input=input, truncate=truncate, options=options, keep_alive=keep_alive)
            if hasattr(async_gen, "model_dump_json"):
                json_line = async_gen.model_dump_json()
            else:
                json_line = json.dumps(async_gen)
            yield json_line.encode("utf-8") + b"\n"
        finally:
            # Ensure counter is decremented even if an exception occurs
            await decrement_usage(endpoint, model)

    # 4. Return a StreamingResponse backed by the generator
    return StreamingResponse(
        stream_embedding_response(),
        media_type="application/json",
    )

# -------------------------------------------------------------
# 10. API route – Create
# -------------------------------------------------------------
@app.post("/api/create")
async def create_proxy(request: Request):
    """
    Proxy a create request to all Ollama endpoints and reply with deduplicated status.
    """
    try:
        body_bytes = await request.body()
        payload = json.loads(body_bytes.decode("utf-8"))

        model = payload.get("model")
        quantize = payload.get("quantize")
        from_ = payload.get("from")
        files = payload.get("files")
        adapters = payload.get("adapters")
        template = payload.get("template")
        license = payload.get("license")
        system = payload.get("system")
        parameters = payload.get("parameters")
        messages = payload.get("messages")
        
        if not model:
            raise HTTPException(
                status_code=400, detail="Missing required field 'model'"
            )
        if not from_ and not files:
            raise HTTPException(
                status_code=400, detail="You need to provide either from_ or files parameter!"
            )
    except json.JSONDecodeError as e:
        raise HTTPException(status_code=400, detail=f"Invalid JSON: {e}") from e
    
    status_lists = []
    for endpoint in config.endpoints:
        client = ollama.AsyncClient(host=endpoint)
        create = await client.create(model=model, quantize=quantize, from_=from_, files=files, adapters=adapters, template=template, license=license, system=system, parameters=parameters, messages=messages, stream=False)
        status_lists.append(create)

    combined_status = []
    for status_list in status_lists:
        combined_status += status_list

    final_status = list(dict.fromkeys(combined_status))

    return dict(final_status)

# -------------------------------------------------------------
# 11. API route – Show
# -------------------------------------------------------------
@app.post("/api/show")
async def show_proxy(request: Request, model: Optional[str] = None):
    """
    Proxy a model show request to Ollama and reply with ShowResponse.

    """
    try:
        body_bytes = await request.body()

        if not model:
            payload = json.loads(body_bytes.decode("utf-8"))
            model = payload.get("model")
        
        if not model:
            raise HTTPException(
                status_code=400, detail="Missing required field 'model'"
            )
    except json.JSONDecodeError as e:
        raise HTTPException(status_code=400, detail=f"Invalid JSON: {e}") from e

    # 2. Endpoint logic
    endpoint = await choose_endpoint(model)
    #await increment_usage(endpoint, model)
    client = ollama.AsyncClient(host=endpoint)

    # 3. Proxy a simple show request
    show = await client.show(model=model)

    # 4. Return ShowResponse
    return show

# -------------------------------------------------------------
# 12. API route – Copy
# -------------------------------------------------------------
@app.post("/api/copy")
async def copy_proxy(request: Request, source: Optional[str] = None, destination: Optional[str] = None):
    """
    Proxy a model copy request to each Ollama endpoint and reply with Status Code.

    """
    # 1. Parse and validate request
    try:
        body_bytes = await request.body()

        if not source and not destination:
            payload = json.loads(body_bytes.decode("utf-8"))
            src = payload.get("source")
            dst = payload.get("destination")
        else:
            src = source
            dst = destination
        
        if not src:
            raise HTTPException(
                status_code=400, detail="Missing required field 'source'"
            )
        if not dst:
            raise HTTPException(
                status_code=400, detail="Missing required field 'destination'"
            )
    except json.JSONDecodeError as e:
        raise HTTPException(status_code=400, detail=f"Invalid JSON: {e}") from e

    # 3. Iterate over all endpoints to copy the model on each endpoint
    status_list = []
    for endpoint in config.endpoints:
        if "/v1" not in endpoint:
            client = ollama.AsyncClient(host=endpoint)
            # 4. Proxy a simple copy request
            copy = await client.copy(source=src, destination=dst)
            status_list.append(copy.status)

    # 4. Return with 200 OK if all went well, 404 if a single endpoint failed
    return Response(status_code=404 if 404 in status_list else 200)

# -------------------------------------------------------------
# 13. API route – Delete
# -------------------------------------------------------------
@app.delete("/api/delete")
async def delete_proxy(request: Request, model: Optional[str] = None):
    """
    Proxy a model delete request to each Ollama endpoint and reply with Status Code.

    """
    # 1. Parse and validate request
    try:
        body_bytes = await request.body()

        if not model:
            payload = json.loads(body_bytes.decode("utf-8"))
            model = payload.get("model")
        
        if not model:
            raise HTTPException(
                status_code=400, detail="Missing required field 'model'"
            )
    except json.JSONDecodeError as e:
        raise HTTPException(status_code=400, detail=f"Invalid JSON: {e}") from e

    # 2. Iterate over all endpoints to delete the model on each endpoint
    status_list = []
    for endpoint in config.endpoints:
        if "/v1" not in endpoint:
            client = ollama.AsyncClient(host=endpoint)
            # 3. Proxy a simple copy request
            copy = await client.delete(model=model)
            status_list.append(copy.status)
    
    # 4. Retrun 200 0K, if a single enpoint fails, respond with 404
    return Response(status_code=404 if 404 in status_list else 200)   

# -------------------------------------------------------------
# 14. API route – Pull
# -------------------------------------------------------------
@app.post("/api/pull")
async def pull_proxy(request: Request, model: Optional[str] = None):
    """
    Proxy a pull request to all Ollama endpoint and report status back.
    """
    # 1. Parse and validate request
    try:
        body_bytes = await request.body()

        if not model:
            payload = json.loads(body_bytes.decode("utf-8"))
            model = payload.get("model")
            insecure = payload.get("insecure")
        else:
            insecure = None

        if not model:
            raise HTTPException(
                status_code=400, detail="Missing required field 'model'"
            )
    except json.JSONDecodeError as e:
        raise HTTPException(status_code=400, detail=f"Invalid JSON: {e}") from e

    # 2. Iterate over all endpoints to pull the model
    status_list = []
    for endpoint in config.endpoints:
        if "/v1" not in endpoint:
            client = ollama.AsyncClient(host=endpoint)
            # 3. Proxy a simple pull request
            pull = await client.pull(model=model, insecure=insecure, stream=False)
            status_list.append(pull)

    combined_status = []
    for status in status_list:
        combined_status += status
    
    # 4. Report back a deduplicated status message
    final_status = list(dict.fromkeys(combined_status))

    return dict(final_status)

# -------------------------------------------------------------
# 15. API route – Push
# -------------------------------------------------------------
@app.post("/api/push")
async def push_proxy(request: Request):
    """
    Proxy a push request to Ollama and respond the deduplicated Ollama endpoint replies.
    """
    # 1. Parse and validate request
    try:
        body_bytes = await request.body()
        payload = json.loads(body_bytes.decode("utf-8"))

        model = payload.get("model")
        insecure = payload.get("insecure")

        if not model:
            raise HTTPException(
                status_code=400, detail="Missing required field 'model'"
            )
    except json.JSONDecodeError as e:
        raise HTTPException(status_code=400, detail=f"Invalid JSON: {e}") from e

    # 2. Iterate over all endpoints
    status_list = []
    for endpoint in config.endpoints:
        client = ollama.AsyncClient(host=endpoint)
        # 3. Proxy a simple push request
        push = await client.push(model=model, insecure=insecure, stream=False)
        status_list.append(push)

    combined_status = []
    for status in status_list:
        combined_status += status
    
    # 4. Report a deduplicated status
    final_status = list(dict.fromkeys(combined_status))

    return dict(final_status)


# -------------------------------------------------------------
# 16. API route – Version
# -------------------------------------------------------------
@app.get("/api/version")
async def version_proxy(request: Request):
    """
    Proxy a version request to Ollama and reply lowest version of all endpoints.

    """
    # 1. Query all endpoints for version
    tasks = [fetch_endpoint_details(ep, "/api/version", "version") for ep in config.endpoints if "/v1" not in ep]
    all_versions = await asyncio.gather(*tasks)

    def version_key(v):
        return tuple(map(int, v.split('.')))
    
    # 2. Return a JSONResponse with the min Version of all endpoints to maintain compatibility
    return JSONResponse(
        content={"version": str(min(all_versions, key=version_key))},
        status_code=200,
    )

# -------------------------------------------------------------
# 17. API route – tags
# -------------------------------------------------------------
@app.get("/api/tags")
async def tags_proxy(request: Request):
    """
    Proxy a tags request to Ollama endpoints and reply with a unique list of all models.

    """
    
    # 1. Query all endpoints for models
    tasks = [fetch_endpoint_details(ep, "/api/tags", "models") for ep in config.endpoints if "/v1" not in ep]
    tasks += [fetch_endpoint_details(ep, "/models", "data", config.api_keys[ep]) for ep in config.endpoints if "/v1" in ep]
    all_models = await asyncio.gather(*tasks)
    
    models = {'models': []}
    for modellist in all_models:
        models['models'] += modellist
    
    # 2. Return a JSONResponse with a deduplicated list of unique models for inference
    return JSONResponse(
        content={"models": dedupe_on_keys(models['models'], ['digest','name','id'])},
        status_code=200,
    )

# -------------------------------------------------------------
# 18. API route – ps
# -------------------------------------------------------------
@app.get("/api/ps")
async def ps_proxy(request: Request):
    """
    Proxy a ps request to all Ollama endpoints and reply a unique list of all running models.

    """
    # 1. Query all endpoints for running models
    tasks = [fetch_endpoint_details(ep, "/api/ps", "models") for ep in config.endpoints if "/v1" not in ep]
    loaded_models = await asyncio.gather(*tasks)

    models = {'models': []}
    for modellist in loaded_models:
        models['models'] += modellist
    
    # 2. Return a JSONResponse with deduplicated currently deployed models
    return JSONResponse(
        content={"models": dedupe_on_keys(models['models'], ['digest'])},
        status_code=200,
    )

# -------------------------------------------------------------
# 19. Proxy usage route – for monitoring
# -------------------------------------------------------------
@app.get("/api/usage")
async def usage_proxy(request: Request):
    """
    Return a snapshot of the usage counter for each endpoint.
    Useful for debugging / monitoring.
    """
    return {"usage_counts": usage_counts}

# -------------------------------------------------------------
# 20. Proxy config route – for monitoring and frontent usage
# -------------------------------------------------------------
@app.get("/api/config")
async def config_proxy(request: Request):
    """
    Return a simple JSON object that contains the configured
    Ollama endpoints. The front‑end uses this to display
    which endpoints are being proxied.
    """
    async def check_endpoint(url: str):
        try:
            client: aiohttp.ClientSession = app_state["session"]
            if "/v1" in url:
                headers = {"Authorization": "Bearer " + config.api_keys[url]}
                async with client.get(f"{url}/models", headers=headers) as resp:
                    await _ensure_success(resp)
                    data = await resp.json()
            else:
                async with client.get(f"{url}/api/version") as resp:
                    await _ensure_success(resp)
                    data = await resp.json()
            if "/v1" in url:
                return {"url": url, "status": "ok", "version": "latest"}
            else:
                return {"url": url, "status": "ok", "version": data.get("version")}
        except Exception as exc:
            return {"url": url, "status": "error", "detail": str(exc)}

    results = await asyncio.gather(*[check_endpoint(ep) for ep in config.endpoints])
    return {"endpoints": results}

# -------------------------------------------------------------
# 21. API route – OpenAI compatible Embedding
# -------------------------------------------------------------
@app.post("/v1/embeddings")
async def openai_embedding_proxy(request: Request):
    """
    Proxy an OpenAI API compatible embedding request to Ollama and reply with embeddings.

    """
    # 1. Parse and validate request
    try:
        body_bytes = await request.body()
        payload = json.loads(body_bytes.decode("utf-8"))

        model = payload.get("model")
        input = payload.get("input")
        

        if not model:
            raise HTTPException(
                status_code=400, detail="Missing required field 'model'"
            )
        if not input:
            raise HTTPException(
                status_code=400, detail="Missing required field 'input'"
            )
    except json.JSONDecodeError as e:
        raise HTTPException(status_code=400, detail=f"Invalid JSON: {e}") from e

    # 2. Endpoint logic
    endpoint = await choose_endpoint(model)
    await increment_usage(endpoint, model)
    if "/v1" in endpoint:
        api_key = config.api_keys[endpoint]
    else:
        api_key = "ollama"
    oclient = openai.AsyncOpenAI(base_url=endpoint+"/v1", api_key=api_key)

    # 3. Async generator that streams embedding data and decrements the counter
    async_gen = await oclient.embeddings.create(input=[input], model=model)
            
    await decrement_usage(endpoint, model)

    # 5. Return a StreamingResponse backed by the generator
    return async_gen

# -------------------------------------------------------------
# 22. API route – OpenAI compatible Chat Completions
# -------------------------------------------------------------
@app.post("/v1/chat/completions")
async def openai_chat_completions_proxy(request: Request):
    """
    Proxy an OpenAI API compatible chat completions request to Ollama and reply with a streaming response.

    """
    # 1. Parse and validate request
    try:
        body_bytes = await request.body()
        payload = json.loads(body_bytes.decode("utf-8"))

        model = payload.get("model")
        messages = payload.get("messages")
        frequency_penalty = payload.get("frequency_penalty")
        presence_penalty = payload.get("presence_penalty")
        response_format = payload.get("response_format")
        seed = payload.get("seed")
        stop = payload.get("stop")
        stream = payload.get("stream")
        stream_options = payload.get("stream_options")
        temperature = payload.get("temperature")
        top_p = payload.get("top_p")
        max_tokens = payload.get("max_tokens")
        max_completion_tokens = payload.get("max_completion_tokens")
        tools = payload.get("tools")

        params = {
            "messages": messages, 
            "model": model,
        }

        if tools is not None:
            params["tools"] = tools
        if response_format is not None:
            params["response_format"] = response_format
        if stream_options is not None:
            params["stream_options"] = stream_options
        if max_completion_tokens is not None:
            params["max_completion_tokens"] = max_completion_tokens
        if max_tokens is not None:
            params["max_tokens"] = max_tokens
        if temperature is not None:
            params["temperature"] = temperature
        if top_p is not None:
            params["top_p"] = top_p
        if seed is not None:
            params["seed"] = seed
        if presence_penalty is not None:
            params["presence_penalty"] = presence_penalty
        if frequency_penalty is not None:
            params["frequency_penalty"] = frequency_penalty
        if stop is not None:
            params["stop"] = stop
        if stream is not None:
            params["stream"] = stream
        
        
        if not model:
            raise HTTPException(
                status_code=400, detail="Missing required field 'model'"
            )
        if not isinstance(messages, list):
            raise HTTPException(
                status_code=400, detail="Missing required field 'messages' (must be a list)"
            )
    except json.JSONDecodeError as e:
        raise HTTPException(status_code=400, detail=f"Invalid JSON: {e}") from e

    # 2. Endpoint logic
    endpoint = await choose_endpoint(model)
    await increment_usage(endpoint, model)
    base_url = ep2base(endpoint)
    oclient = openai.AsyncOpenAI(base_url=base_url, api_key=config.api_keys[endpoint])
    
    # 3. Async generator that streams completions data and decrements the counter
    async def stream_ochat_response():
        try:
            # The chat method returns a generator of dicts (or GenerateResponse)
            async_gen = await oclient.chat.completions.create(**params)
            if stream == True:
                async for chunk in async_gen:
                    data = (
                        chunk.model_dump_json()
                        if hasattr(chunk, "model_dump_json")
                        else json.dumps(chunk)
                    )
                    yield f"data: {data}\n\n".encode("utf-8")
                # Final DONE event
                yield b"data: [DONE]\n\n"
            else:
                json_line = (
                    async_gen.model_dump_json()
                    if hasattr(async_gen, "model_dump_json")
                    else json.dumps(async_gen)
                )
                yield json_line.encode("utf-8") + b"\n"

        finally:
            # Ensure counter is decremented even if an exception occurs
            await decrement_usage(endpoint, model)

    # 4. Return a StreamingResponse backed by the generator
    return StreamingResponse(
        stream_ochat_response(),
        media_type="application/json",
    )

# -------------------------------------------------------------
# 23. API route – OpenAI compatible Completions
# -------------------------------------------------------------
@app.post("/v1/completions")
async def openai_completions_proxy(request: Request):
    """
    Proxy an OpenAI API compatible chat completions request to Ollama and reply with a streaming response.

    """
    # 1. Parse and validate request
    try:
        body_bytes = await request.body()
        payload = json.loads(body_bytes.decode("utf-8"))

        model = payload.get("model")
        prompt = payload.get("prompt")
        frequency_penalty = payload.get("frequency_penalty")
        presence_penalty = payload.get("presence_penalty")
        seed = payload.get("seed")
        stop = payload.get("stop")
        stream = payload.get("stream")
        stream_options = payload.get("stream_options")
        temperature = payload.get("temperature")
        top_p = payload.get("top_p")
        max_tokens = payload.get("max_tokens")
        max_completion_tokens = payload.get("max_completion_tokens")
        suffix = payload.get("suffix")

        params = {
            "prompt": prompt, 
            "model": model,
        }

        if stream_options is not None:
            params["stream_options"] = stream_options
        if frequency_penalty is not None:
            params["frequency_penalty"] = frequency_penalty
        if presence_penalty is not None:
            params["presence_penalty"] = presence_penalty
        if seed is not None:
            params["seed"] = seed
        if stop is not None:
            params["stop"] = stop
        if stream is not None:
            params["stream"] = stream
        if temperature is not None:
            params["temperature"] = temperature
        if top_p is not None:
            params["top_p"] = top_p
        if max_tokens is not None:
            params["max_tokens"] = max_tokens
        if suffix is not None:
            params["suffix"] = suffix

        if not model:
            raise HTTPException(
                status_code=400, detail="Missing required field 'model'"
            )
        if not prompt:
            raise HTTPException(
                status_code=400, detail="Missing required field 'prompt'"
            )
    except json.JSONDecodeError as e:
        raise HTTPException(status_code=400, detail=f"Invalid JSON: {e}") from e

    # 2. Endpoint logic
    endpoint = await choose_endpoint(model)
    await increment_usage(endpoint, model)
    base_url = ep2base(endpoint)
    oclient = openai.AsyncOpenAI(base_url=base_url, api_key=config.api_keys[endpoint])

    # 3. Async generator that streams completions data and decrements the counter
    async def stream_ocompletions_response():
        try:
            # The chat method returns a generator of dicts (or GenerateResponse)
            async_gen = await oclient.completions.create(**params)
            if stream == True:
                async for chunk in async_gen:
                    data = (
                        chunk.model_dump_json()
                        if hasattr(chunk, "model_dump_json")
                        else json.dumps(chunk)
                    )
                    yield f"data: {data}\n\n".encode("utf-8")
                # Final DONE event
                yield b"data: [DONE]\n\n"
            else:
                json_line = (
                    async_gen.model_dump_json()
                    if hasattr(async_gen, "model_dump_json")
                    else json.dumps(async_gen)
                )
                yield json_line.encode("utf-8") + b"\n"

        finally:
            # Ensure counter is decremented even if an exception occurs
            await decrement_usage(endpoint, model)

    # 4. Return a StreamingResponse backed by the generator
    return StreamingResponse(
        stream_ocompletions_response(),
        media_type="application/json",
    )

# -------------------------------------------------------------
# 24. OpenAI API compatible models endpoint
# -------------------------------------------------------------
@app.get("/v1/models")
async def openai_models_proxy(request: Request):
    """
    Proxy an OpenAI API models request to Ollama endpoints and reply with a unique list of all models.

    """
    # 1. Query all endpoints for models
    tasks = [fetch_endpoint_details(ep, "/api/tags", "models") for ep in config.endpoints if "/v1" not in ep]
    tasks += [fetch_endpoint_details(ep, "/models", "data", config.api_keys[ep]) for ep in config.endpoints if "/v1" in ep]
    all_models = await asyncio.gather(*tasks)
    
    models = {'data': []}
    for modellist in all_models:
        for model in modellist:
            if not "id" in model.keys():  # Relable Ollama models with OpenAI Model.id from Model.name
                model['id'] = model['name']
            else:
                model['name'] = model['id']
        models['data'] += modellist
    
    # 2. Return a JSONResponse with a deduplicated list of unique models for inference
    return JSONResponse(
        content={"data": dedupe_on_keys(models['data'], ['name'])},
        status_code=200,
    )

# -------------------------------------------------------------
# 25. Serve the static front‑end
# -------------------------------------------------------------
app.mount("/static", StaticFiles(directory="static"), name="static")

@app.get("/favicon.ico")
async def redirect_favicon():
    return RedirectResponse(url="/static/favicon.ico")

@app.get("/", response_class=HTMLResponse)
async def index(request: Request):
    """
    Render the dynamic NOMYO Router dashboard listing the configured endpoints
    and the models details, availability & task status.
    """
    return HTMLResponse(content=open("static/index.html", "r").read(), status_code=200)

# -------------------------------------------------------------
# 26. Healthendpoint
# -------------------------------------------------------------
@app.get("/health")
async def health_proxy(request: Request):
    """
    Health‑check endpoint for monitoring the proxy.

    * Queries each configured endpoint for its `/api/version` response.
    * Returns a JSON object containing:
        - `status`: "ok" if every endpoint replied, otherwise "error".
        - `endpoints`: a mapping of endpoint URL → `{status, version|detail}`.
    * The HTTP status code is 200 when everything is healthy, 503 otherwise.
    """
    # Run all health checks in parallel
    tasks = [
        fetch_endpoint_details(ep, "/api/version", "version") for ep in config.endpoints
    ]

    results = await asyncio.gather(*tasks, return_exceptions=True)

    health_summary = {}
    overall_ok = True

    for ep, result in zip(config.endpoints, results):
        if isinstance(result, Exception):
            # Endpoint did not respond / returned an error
            health_summary[ep] = {"status": "error", "detail": str(result)}
            overall_ok = False
        else:
            # Successful response – report the reported version
            health_summary[ep] = {"status": "ok", "version": result}

    response_payload = {
        "status": "ok" if overall_ok else "error",
        "endpoints": health_summary,
    }

    http_status = 200 if overall_ok else 503
    return JSONResponse(content=response_payload, status_code=http_status)

# -------------------------------------------------------------
# 27. SSE route for usage broadcasts
# -------------------------------------------------------------
@app.get("/api/usage-stream")
async def usage_stream(request: Request):
    """
    Server‑Sent‑Events that emits a JSON payload every time the
    global `usage_counts` dictionary changes.
    """
    async def event_generator():
        # The queue that receives *every* new snapshot
        queue = await subscribe()
        try:
            while True:
                # If the client disconnects, cancel the loop
                if await request.is_disconnected():
                    break
                data = await queue.get()
                # Send the data as a single SSE message
                yield f"data: {data}\n\n"
        finally:
            # Clean‑up: unsubscribe from the broadcast channel
            await unsubscribe(queue)

    return StreamingResponse(event_generator(), media_type="text/event-stream")

# -------------------------------------------------------------
# 28. FastAPI startup/shutdown events
# -------------------------------------------------------------
@app.on_event("startup")
async def startup_event() -> None:
    global config
    # Load YAML config (or use defaults if not present)
    config = Config.from_yaml(Path("config.yaml"))
    print(f"Loaded configuration:\n endpoints={config.endpoints},\n "
          f"max_concurrent_connections={config.max_concurrent_connections}")
    
    ssl_context = ssl.create_default_context()
    connector = aiohttp.TCPConnector(limit=0, limit_per_host=512, ssl=ssl_context)
    timeout = aiohttp.ClientTimeout(total=5, connect=5, sock_read=120, sock_connect=5)
    session = aiohttp.ClientSession(connector=connector, timeout=timeout)

    app_state["connector"] = connector
    app_state["session"] = session


@app.on_event("shutdown")
async def shutdown_event() -> None:
    await app_state["session"].close()