"""
Renders a ui_spec dict to GitHub-flavored markdown.

Used by the Custom GPT Action path (Path A) where real interactive UI
is not available. Interactive behaviour degrades to descriptive markdown.
"""


def render(spec: dict | None) -> str | None:
    if not spec:
        return None

    component = spec.get("component", "")
    props = spec.get("props", {})

    renderers = {
        "form":    _form,
        "chart":   _chart,
        "card":    _card,
        "table":   _table,
        "figures": _figures,
    }
    fn = renderers.get(component)
    return fn(props) if fn else f"*[{component} — view in full UI for interactivity]*"


# ── form ─────────────────────────────────────────────────────────────────────

def _form(props: dict) -> str:
    lines: list[str] = []

    title = props.get("title")
    if title:
        lines.append(f"**{title}**\n")

    for f in props.get("fields", []):
        label    = f.get("label") or f.get("name", "")
        ftype    = f.get("type", "text")
        required = " *(required)*" if f.get("required") else ""
        hint     = f" — {f['hint']}" if f.get("hint") else ""
        lines.append(f"- **{label}** `{ftype}`{required}{hint}")

    submit = props.get("submitLabel", "Submit")
    lines.append(f"\n> *(Use the full UI widget to fill and submit — **{submit}**)*")
    return "\n".join(lines)


# ── chart ─────────────────────────────────────────────────────────────────────

def _chart(props: dict) -> str:
    title      = props.get("title", "Chart")
    chart_type = props.get("type", "")
    lines      = [f"**{title}** *(interactive {chart_type} chart in full UI)*\n"]

    data     = props.get("data", {})
    labels   = data.get("labels", [])
    datasets = data.get("datasets", [])

    if labels and datasets:
        header = "| Label | " + " | ".join(ds.get("label", "Value") for ds in datasets) + " |"
        sep    = "|---|" + "---|" * len(datasets)
        lines += [header, sep]
        for i, lbl in enumerate(labels):
            cells = [str(ds.get("data", [])[i]) if i < len(ds.get("data", [])) else "" for ds in datasets]
            lines.append(f"| {lbl} | " + " | ".join(cells) + " |")

    return "\n".join(lines)


# ── card ──────────────────────────────────────────────────────────────────────

def _card(props: dict) -> str:
    lines: list[str] = []

    if title := props.get("title"):
        lines.append(f"### {title}")
    if body := props.get("body"):
        lines.append(body)

    for item in props.get("items", []):
        if isinstance(item, dict):
            key = item.get("label") or item.get("key", "")
            lines.append(f"- **{key}**: {item.get('value', '')}")
        else:
            lines.append(f"- {item}")

    return "\n".join(lines)


# ── table ─────────────────────────────────────────────────────────────────────

def _table(props: dict) -> str:
    columns = props.get("columns", [])
    rows    = props.get("rows", [])

    if not columns:
        return "*[empty table]*"

    header = "| " + " | ".join(columns) + " |"
    sep    = "|" + "---|" * len(columns)
    lines  = [header, sep]

    for row in rows:
        if isinstance(row, dict):
            cells = [str(row.get(col, "")) for col in columns]
        elif isinstance(row, list):
            cells = [str(c) for c in row]
        else:
            cells = [str(row)]
        lines.append("| " + " | ".join(cells) + " |")

    return "\n".join(lines)


# ── figures ───────────────────────────────────────────────────────────────────

def _figures(props: dict) -> str:
    lines: list[str] = []
    if title := props.get("title"):
        lines.append(f"**{title}**\n")
    for f in props.get("fields", []):
        label = f.get("label") or f.get("name", "")
        value = f.get("value", 0)
        unit  = f" {f['unit']}" if f.get("unit") else ""
        lines.append(f"- **{label}**: {value}{unit}")
    cta = props.get("cta", "Analyze my figures")
    lines.append(f"\n> *(Enter figures in the widget then click **{cta}**)*")
    return "\n".join(lines)