use std::error::Error;
use std::fs;
use std::path::{Path, PathBuf};
use rust_xlsxwriter::*;
use crate::template::antares::Antares;

fn resolve_excel_path(path_str: &str) -> Result<PathBuf, Box<dyn Error>> {
    let path = Path::new(path_str);

    // If path ends with .xlsx, treat it as a file path
    if path_str.ends_with(".xlsx") {
        // Create parent directories if needed
        if let Some(parent) = path.parent() {
            if !parent.as_os_str().is_empty() {
                fs::create_dir_all(parent)?;
            }
        }
        return Ok(path.to_path_buf());
    }

    // If path has an extension but it's not .xlsx, error out
    if path.extension().is_some() {
        return Err(format!(
            "Invalid file extension. Expected .xlsx, got: {}",
            path_str
        )
        .into());
    }

    // Otherwise, treat as directory and create antares.xlsx inside
    fs::create_dir_all(path)?;
    Ok(path.join("antares.xlsx"))
}

pub fn export_to_excel(items: &Antares, path_str: &str) -> Result<(), Box<dyn Error>> {
    let output_path = resolve_excel_path(path_str)?;
    
    let mut workbook = Workbook::new();
    let sheet = workbook.add_worksheet();
    
    let header_format = Format::new().set_bold();
    
    // Write headers
    sheet.write_string_with_format(0, 0, "BESZCIKKSZAM", &header_format)?;
    sheet.write_string_with_format(0, 1, "GYCIKKSZAM", &header_format)?;
    sheet.write_string_with_format(0, 2, "BESZCIKKNEV", &header_format)?;
    sheet.write_string_with_format(0, 3, "GYARTO", &header_format)?;
    sheet.write_string_with_format(0, 4, "CIKKAZON", &header_format)?;
    sheet.write_string_with_format(0, 5, "KESZLET", &header_format)?;
    sheet.write_string_with_format(0, 6, "ME", &header_format)?;
    sheet.write_string_with_format(0, 7, "EGYSEGAR", &header_format)?;

    let mut row = 1u32;
    for item in items {
        // Skip if BESZCIKKSZAM is empty
        let cikkszam = match &item.cikkszam {
            Some(cs) if !cs.is_empty() => cs.clone(),
            _ => continue,
        };

        // BESZCIKKNEV: cikk_megnevezes_rovid or cikk_megnevezes
        let megnevezes = item
            .cikk_megnevezes_rovid
            .clone()
            .or_else(|| item.cikk_megnevezes.clone())
            .unwrap_or_default();
        
        // Skip if BESZCIKKNEV is empty
        if megnevezes.is_empty() {
            continue;
        }

        // EGYSEGAR: netto_kisker_ar or find in cikk_jellemzok where jellemzo_nev = "Alap ár"
        let mut unit_price = item.netto_kisker_ar.unwrap_or(0.0);
        if unit_price == 0.0 {
            if let Some(ref jellemzok) = item.cikk_jellemzok {
                for jellemzo in jellemzok {
                    if let Some(ref nev) = jellemzo.jellemzo_nev {
                        if nev == "Alap ár" {
                            if let Some(ref ertek) = jellemzo.jellemzo_ertek {
                                unit_price = ertek.parse().unwrap_or(0.0);
                                break;
                            }
                        }
                    }
                }
            }
        }

        // Write row data
        if unit_price == 0.0 {
            continue;
        }
        sheet.write_string(row, 0, &cikkszam)?;
        sheet.write_string(row, 1, &cikkszam)?;
        sheet.write_string(row, 2, &megnevezes)?;
        sheet.write_string(row, 3, "EGYEB")?;
        sheet.write_string(row, 4, item.vonalkod.as_deref().unwrap_or(""))?;
        sheet.write_number(row, 5, item.szabad_keszlet.unwrap_or(0) as f64)?;
        sheet.write_string(row, 6, item.mennyisegi_egyseg_kod.as_deref().unwrap_or(""))?;
        sheet.write_number(row, 7, unit_price)?;

        row += 1;
    }

    workbook.save(&output_path)?;
    let display_path = output_path.display();
    println!("Excel file '{}' created with {} rows", display_path, row - 1);
    Ok(())
}