"""Prompt registry and rendering API."""

from __future__ import annotations

from typing import Any

from capabilities import require_capability_ctx
from fastapi import APIRouter, Depends, HTTPException
from prompt_context import merge_context_values
from prompt_registry import list_prompt_definitions, load_active_prompt_version, load_prompt_definition
from prompt_rendering import PromptRenderError, render_prompt_single
from pydantic import BaseModel, Field
from tenant_context import TenantContext

router = APIRouter(prefix="/api/prompts", tags=["prompts"])


class RenderPromptRequest(BaseModel):
    values: dict[str, Any] = Field(default_factory=dict)
    use_context: bool = True


@router.get("")
def list_prompts(_ctx=Depends(require_capability_ctx("kairo.prompt.registry.read"))):
    return list_prompt_definitions()


@router.get("/{prompt_key}")
def get_prompt(prompt_key: str, _ctx=Depends(require_capability_ctx("kairo.prompt.registry.read"))):
    definition = load_prompt_definition(prompt_key)
    if not definition:
        raise HTTPException(status_code=404, detail="Prompt nicht gefunden")
    version = load_active_prompt_version(definition)
    return {
        "definition": definition,
        "active_version": version,
    }


@router.post("/{prompt_key}/render")
def render_prompt(
    prompt_key: str,
    body: RenderPromptRequest,
    ctx: TenantContext = Depends(require_capability_ctx("kairo.prompt.render")),
):
    definition = load_prompt_definition(prompt_key)
    if not definition:
        raise HTTPException(status_code=404, detail="Prompt nicht gefunden")

    if body.use_context and definition["context_kind"] in (
        "kairo.tenant_context",
        "kairo.actor_context",
    ):
        if not ctx.tenant_id:
            raise HTTPException(status_code=403, detail="Aktiver Tenant erforderlich für diesen Prompt")

    values = body.values
    if body.use_context:
        values = merge_context_values(ctx, definition["context_kind"], body.values)

    try:
        return render_prompt_single(
            prompt_key,
            values=values,
            user_id=ctx.user_id,
            log_execution=True,
        )
    except PromptRenderError as exc:
        status = 400
        if exc.code == "not_found":
            status = 404
        elif exc.code == "mode_not_implemented":
            status = 501
        raise HTTPException(status_code=status, detail=str(exc)) from exc