use super::{
    CellRef, EngineError, HAlign, Json, NumFmt, Result, Session, Value, bad, bool_param, cell_param, cell_param_on, edit, json, object_params, ok,
    str_param, target_ranges, target_sheet,
};

/// Whether `c` has checkbox formatting.
pub(crate) fn is_checkbox_cell(wb: &gridcraft_model::Workbook, sh: &gridcraft_model::Sheet, c: CellRef) -> bool {
    wb.styles.get(sh.style_id(c)).num_fmt.as_str() == "checkbox"
}

pub(super) fn checkbox(s: &mut Session, p: &Json) -> Result<Json> {
    let ranges = target_ranges(s, p)?;
    let si = target_sheet(s, p)?;
    edit(s, |cx| {
        for r in &ranges {
            if r.count() > 100_000 {
                return Err(bad("insert.checkbox", "range too large"));
            }
            for c in r.iter() {
                let st = cx.wb.sheet(si).map(|sh| sh.style_id(c)).unwrap_or_default();
                let new = cx.wb.styles.derive(st, |s| {
                    s.num_fmt = NumFmt::new("checkbox");
                    s.align.h = HAlign::Center;
                });
                let sh = cx.sheet_mut(si)?;
                // Values and formulas already there stay (only TRUE/FALSE draw as a box); an empty
                // cell starts unchecked.
                let mut cell = sh.cell(c).cloned().unwrap_or_default();
                if cell.value.is_empty() && cell.formula.is_none() {
                    cell.value = Value::Bool(false);
                }
                cell.style = new;
                sh.set_cell(c, cell);
                cx.touch(si, c);
            }
        }
        Ok(Json::Null)
    })
}

pub(super) fn toggle_checkbox(s: &mut Session, p: &Json) -> Result<Json> {
    let si = target_sheet(s, p)?;
    let d = s.doc()?;
    let cells: Vec<CellRef> = match cell_param_on(s, p, "cell", si)? {
        Some(c) => vec![c],
        None => d.selection.ranges.iter().flat_map(|r| r.iter().take(100_000).collect::<Vec<_>>()).collect(),
    };
    edit(s, |cx| {
        for c in cells {
            let checkbox = cx.wb.sheet(si).is_some_and(|sh| is_checkbox_cell(&cx.wb, sh, c));
            let sh = cx.sheet_mut(si)?;
            if let Some(cell) = sh.cells.get_mut(c)
                && cell.formula.is_none()
                && cell.py.is_none()
            {
                // An empty checkbox cell counts as FALSE.
                let next = match cell.value {
                    Value::Bool(b) if checkbox => Value::Bool(!b),
                    Value::Empty if checkbox => Value::Bool(true),
                    _ => continue,
                };
                cell.value = next;
                cx.changed.push((si, c));
            }
        }
        Ok(Json::Null)
    })
}

pub(super) fn theme_colors(s: &mut Session, p: &Json) -> Result<Json> {
    let mut params = object_params(p);
    if params.get("name").is_none() {
        params["name"] = json!(s.doc()?.wb.theme.name.clone());
    }
    s.execute("pageLayout.theme", params)
}

pub(super) fn theme_fonts(s: &mut Session, p: &Json) -> Result<Json> {
    let name = s.doc()?.wb.theme.name.clone();
    let colors: Vec<String> = s.doc()?.wb.theme.colors.iter().map(|c| format!("#{c:06X}")).collect();
    s.execute("pageLayout.theme", json!({"name": name, "colors": colors, "majorFont": p.get("major"), "minorFont": p.get("minor")}))
}

pub(super) fn background(s: &mut Session, p: &Json) -> Result<Json> {
    if bool_param(p, "clear").unwrap_or(false) {
        let si = s.doc()?.wb.active_sheet();
        return edit(s, |cx| {
            cx.sheet_mut(si)?.images.retain(|i| i.alt != "Sheet background");
            Ok(Json::Null)
        });
    }
    let mut params = object_params(p);
    params["alt"] = json!("Sheet background");
    params["at"] = json!("A1");
    s.execute("insert.picture", params)
}

pub(super) fn draw_border(s: &mut Session, p: &Json) -> Result<Json> {
    let edge = str_param(p, "edge").unwrap_or("grid");
    let preset = match edge {
        "top" => "top",
        "bottom" => "bottom",
        "left" => "left",
        "right" => "right",
        "outline" => "outside",
        _ => "all",
    };
    let mut params = object_params(p);
    params["preset"] = json!(preset);
    s.execute("home.borders", params)
}

pub(super) fn new_cell_style(s: &mut Session, p: &Json) -> Result<Json> {
    let name = str_param(p, "name").ok_or_else(|| bad("home.newCellStyle", "missing `name`"))?.to_string();
    let d = s.doc()?;
    let sh = d.wb.active().ok_or(EngineError::NoDocument)?;
    let c = cell_param(s, p, "fromCell")?.unwrap_or(d.selection.active);
    let style = d.wb.styles.get(sh.style_id(c)).clone();
    edit(s, |cx| {
        cx.wb.cell_styles.retain(|(n, _)| !n.eq_ignore_ascii_case(&name));
        cx.wb.cell_styles.push((name.clone(), style.clone()));
        Ok(json!({"name": name}))
    })
}

/// Formulas › Recently Used: the functions most recently entered in a formula, newest first
/// ([`crate::Prefs::recent_functions`]).
pub(super) fn recently_used(s: &mut Session, _: &Json) -> Result<Json> {
    Ok(json!(s.prefs.recent_functions))
}

pub(super) fn use_in_formula(s: &mut Session, p: &Json) -> Result<Json> {
    let name = str_param(p, "name").ok_or_else(|| bad("formulas.useInFormula", "missing `name`"))?;
    s.ui_requests.push(crate::UiRequest::InsertName(name.to_string()));
    ok()
}