# state.py
"""Shared Gradio state helpers."""

from __future__ import annotations

from typing import List, Literal, Optional

SearchMode = Literal["all", "single"]
AppMode = Literal["qa", "summary", "ocr", "entities", "documents"]

MODE_LABELS: dict[AppMode, str] = {
    "qa": "Finance QA Chatbot",
    "summary": "Financial Summary",
    "ocr": "Document OCR",
    "entities": "Entity Extraction",
    "documents": "Documents",
}


def default_search_mode() -> SearchMode:
    return "all"


def default_app_mode() -> AppMode:
    return "qa"


def default_selected_doc_ids() -> List[str]:
    return []


def default_session_id() -> Optional[str]:
    return None


def mode_label(search_mode: SearchMode) -> str:
    return "Hybrid RAG" if search_mode == "all" else "Single Document"


def center_title(app_mode: AppMode, search_mode: SearchMode) -> str:
    if app_mode == "qa":
        return mode_label(search_mode)
    return MODE_LABELS[app_mode]


def footer_hint(
    search_mode: SearchMode,
    selected_doc_ids: List[str],
    doc_count: int | None = None,
    app_mode: AppMode = "qa",
) -> str:
    if app_mode == "documents":
        indexed = doc_count if doc_count is not None else 0
        return f"Drop a file above or click Upload & index · {indexed} doc(s) indexed"
    if app_mode != "qa":
        return "Tap + to switch features or upload documents"
    base = "Enter sends · Shift+Enter newline"
    mode_key = "hybrid" if search_mode == "all" else "single"
    if search_mode == "single":
        n = len(selected_doc_ids) if selected_doc_ids else 0
        return f"{base} · Mode: {mode_key} · {n} doc(s) selected"
    if selected_doc_ids:
        return f"{base} · Mode: {mode_key} · {len(selected_doc_ids)} doc(s) scoped for RAG"
    indexed = doc_count if doc_count is not None else 0
    return f"{base} · Mode: {mode_key} · {indexed} doc(s) indexed"


DEFAULT_FOOTER = footer_hint("all", [], 0)

WELCOME_MESSAGE = (
    "Hello! I'm **FinSight AI**. Upload a financial document and ask me anything about it — "
    "earnings reports, balance sheets, risk disclosures, or OCR extraction."
)

EMPTY_STATE_HTML = """
<div class="fs-empty-state">
  <div class="fs-empty-logo">FinSight AI</div>
  <p class="fs-empty-sub">Upload financial documents and ask questions about revenue, balance sheets, and more.</p>
</div>
"""