"""Prompt management — view, edit, reload system prompts."""

from __future__ import annotations

from fastapi import APIRouter, HTTPException
from pydantic import BaseModel

from Project.Sanad.config import SCRIPTS_DIR
from Project.Sanad.core.config_loader import section as _cfg_section
from Project.Sanad.dashboard.routes._safe_io import (
    atomic_write_text, MAX_UPLOAD_BYTES,
)

router = APIRouter()

# Filenames — SINGLE SOURCE in core.script_files
_SCRIPTS = _cfg_section("core", "script_files")
SCRIPT_PROMPT_PATH = SCRIPTS_DIR / _SCRIPTS.get("persona", "sanad_script.txt")
RULE_PROMPT_PATH = SCRIPTS_DIR / _SCRIPTS.get("rules", "sanad_rule.txt")
MAX_PROMPT_BYTES = MAX_UPLOAD_BYTES

# Default system prompt — SINGLE SOURCE in core.gemini_defaults
DEFAULT_SYSTEM_PROMPT = _cfg_section("core", "gemini_defaults").get(
    "default_system_prompt",
    "You are Sanad (Bousandah), a wise and friendly Emirati assistant. "
    "Speak strictly in the UAE dialect (Khaleeji). "
    "Be helpful, concise, and use local greetings like 'Marhaba' and 'Ya Khoy'."
)


def _load_system_prompt() -> str:
    try:
        content = SCRIPT_PROMPT_PATH.read_text(encoding="utf-8-sig").strip()
        if content:
            return content
    except FileNotFoundError:
        pass
    return DEFAULT_SYSTEM_PROMPT


def _load_rule_prompts() -> dict[str, str]:
    result = {"system_prompt": "", "replay_prompt": ""}
    try:
        content = RULE_PROMPT_PATH.read_text(encoding="utf-8-sig").strip()
        sections: dict[str, list[str]] = {}
        current = None
        for line in content.splitlines():
            stripped = line.strip()
            if stripped.startswith("[") and stripped.endswith("]"):
                current = stripped[1:-1].strip()
                sections[current] = []
            elif current is not None:
                sections[current].append(line.rstrip())
        result["system_prompt"] = "\n".join(sections.get("SYSTEM_PROMPT", [])).strip()
        result["replay_prompt"] = "\n".join(sections.get("REPLAY_SYSTEM_PROMPT", [])).strip()
    except FileNotFoundError:
        pass
    if not result["system_prompt"]:
        result["system_prompt"] = _load_system_prompt()
    return result


@router.get("/")
async def get_prompt():
    return {
        "script_path": str(SCRIPT_PROMPT_PATH),
        "rule_path": str(RULE_PROMPT_PATH),
        "system_prompt": _load_system_prompt(),
        "rules": _load_rule_prompts(),
    }


class PromptUpdate(BaseModel):
    content: str


@router.post("/update")
async def update_prompt(payload: PromptUpdate):
    if len(payload.content.encode("utf-8")) > MAX_PROMPT_BYTES:
        raise HTTPException(413, f"Prompt too large (max {MAX_PROMPT_BYTES} bytes).")
    try:
        SCRIPTS_DIR.mkdir(parents=True, exist_ok=True)
        atomic_write_text(SCRIPT_PROMPT_PATH, payload.content.rstrip() + "\n")
    except OSError as exc:
        raise HTTPException(500, f"Could not write prompt: {exc}")
    return {"ok": True, "path": str(SCRIPT_PROMPT_PATH), "length": len(payload.content)}


@router.post("/reload")
async def reload_prompts():
    rules = _load_rule_prompts()
    return {
        "ok": True,
        "system_prompt": rules["system_prompt"],
        "replay_prompt": rules["replay_prompt"],
        "script_path": str(SCRIPT_PROMPT_PATH),
        "rule_path": str(RULE_PROMPT_PATH),
    }