use std::{borrow::Cow, cmp::max, num::NonZeroU16};

use crate::{
    app::AppConfigFields,
    canvas::{
        components::data_table::{
            ColumnHeader, DataTableColumn, DataTableProps, DataTableStyling, DataToCell,
            SortColumn, SortDataTable, SortDataTableProps, SortOrder, SortsRow,
        },
        styling::CanvasStyling,
    },
    utils::{data_prefixes::get_decimal_bytes, general::sort_partial_fn},
};

#[derive(Clone, Debug)]
pub struct DiskWidgetData {
    pub name: Cow<'static, str>,
    pub mount_point: Cow<'static, str>,
    pub free_bytes: Option<u64>,
    pub used_bytes: Option<u64>,
    pub total_bytes: Option<u64>,
    pub summed_total_bytes: Option<u64>,
    pub io_read: Cow<'static, str>,
    pub io_write: Cow<'static, str>,
}

impl DiskWidgetData {
    fn total_space(&self) -> Cow<'static, str> {
        if let Some(total_bytes) = self.total_bytes {
            let converted_total_space = get_decimal_bytes(total_bytes);
            format!(
                "{:.*}{}",
                0, converted_total_space.0, converted_total_space.1
            )
            .into()
        } else {
            "N/A".into()
        }
    }

    fn free_space(&self) -> Cow<'static, str> {
        if let Some(free_bytes) = self.free_bytes {
            let converted_free_space = get_decimal_bytes(free_bytes);
            format!("{:.*}{}", 0, converted_free_space.0, converted_free_space.1).into()
        } else {
            "N/A".into()
        }
    }

    fn used_space(&self) -> Cow<'static, str> {
        if let Some(used_bytes) = self.used_bytes {
            let converted_free_space = get_decimal_bytes(used_bytes);
            format!("{:.*}{}", 0, converted_free_space.0, converted_free_space.1).into()
        } else {
            "N/A".into()
        }
    }

    fn free_percent(&self) -> Option<f64> {
        if let (Some(free_bytes), Some(summed_total_bytes)) =
            (self.free_bytes, self.summed_total_bytes)
        {
            Some(free_bytes as f64 / summed_total_bytes as f64 * 100_f64)
        } else {
            None
        }
    }

    fn free_percent_string(&self) -> Cow<'static, str> {
        match self.free_percent() {
            Some(val) => format!("{val:.1}%").into(),
            None => "N/A".into(),
        }
    }

    fn used_percent(&self) -> Option<f64> {
        if let (Some(used_bytes), Some(summed_total_bytes)) =
            (self.used_bytes, self.summed_total_bytes)
        {
            if summed_total_bytes > 0 {
                Some(used_bytes as f64 / summed_total_bytes as f64 * 100_f64)
            } else {
                None
            }
        } else {
            None
        }
    }

    fn used_percent_string(&self) -> Cow<'static, str> {
        match self.used_percent() {
            Some(val) => format!("{val:.1}%").into(),
            None => "N/A".into(),
        }
    }
}

pub enum DiskWidgetColumn {
    Disk,
    Mount,
    Used,
    Free,
    Total,
    UsedPercent,
    FreePercent,
    IoRead,
    IoWrite,
}

impl ColumnHeader for DiskWidgetColumn {
    fn text(&self) -> Cow<'static, str> {
        match self {
            DiskWidgetColumn::Disk => "Disk(d)",
            DiskWidgetColumn::Mount => "Mount(m)",
            DiskWidgetColumn::Used => "Used(u)",
            DiskWidgetColumn::Free => "Free(n)",
            DiskWidgetColumn::UsedPercent => "Used%(p)",
            DiskWidgetColumn::FreePercent => "Free%",
            DiskWidgetColumn::Total => "Total(t)",
            DiskWidgetColumn::IoRead => "R/s(r)",
            DiskWidgetColumn::IoWrite => "W/s(w)",
        }
        .into()
    }
}

impl DataToCell<DiskWidgetColumn> for DiskWidgetData {
    fn to_cell(
        &self, column: &DiskWidgetColumn, _calculated_width: NonZeroU16,
    ) -> Option<Cow<'static, str>> {
        let text = match column {
            DiskWidgetColumn::Disk => self.name.clone(),
            DiskWidgetColumn::Mount => self.mount_point.clone(),
            DiskWidgetColumn::Used => self.used_space(),
            DiskWidgetColumn::Free => self.free_space(),
            DiskWidgetColumn::UsedPercent => self.used_percent_string(),
            DiskWidgetColumn::FreePercent => self.free_percent_string(),
            DiskWidgetColumn::Total => self.total_space(),
            DiskWidgetColumn::IoRead => self.io_read.clone(),
            DiskWidgetColumn::IoWrite => self.io_write.clone(),
        };

        Some(text)
    }

    fn column_widths<C: DataTableColumn<DiskWidgetColumn>>(
        data: &[Self], _columns: &[C],
    ) -> Vec<u16>
    where
        Self: Sized,
    {
        let mut widths = vec![0; 7];

        data.iter().for_each(|row| {
            widths[0] = max(widths[0], row.name.len() as u16);
            widths[1] = max(widths[1], row.mount_point.len() as u16);
        });

        widths
    }
}

pub struct DiskTableWidget {
    pub table: SortDataTable<DiskWidgetData, DiskWidgetColumn>,
    pub force_update_data: bool,
}

impl SortsRow for DiskWidgetColumn {
    type DataType = DiskWidgetData;

    fn sort_data(&self, data: &mut [Self::DataType], descending: bool) {
        match self {
            DiskWidgetColumn::Disk => {
                data.sort_by(|a, b| sort_partial_fn(descending)(&a.name, &b.name));
            }
            DiskWidgetColumn::Mount => {
                data.sort_by(|a, b| sort_partial_fn(descending)(&a.mount_point, &b.mount_point));
            }
            DiskWidgetColumn::Used => {
                data.sort_by(|a, b| sort_partial_fn(descending)(&a.used_bytes, &b.used_bytes));
            }
            DiskWidgetColumn::UsedPercent => {
                data.sort_by(|a, b| {
                    sort_partial_fn(descending)(&a.used_percent(), &b.used_percent())
                });
            }
            DiskWidgetColumn::Free => {
                data.sort_by(|a, b| sort_partial_fn(descending)(&a.free_bytes, &b.free_bytes));
            }
            DiskWidgetColumn::FreePercent => {
                data.sort_by(|a, b| {
                    sort_partial_fn(descending)(&a.free_percent(), &b.free_percent())
                });
            }
            DiskWidgetColumn::Total => {
                data.sort_by(|a, b| sort_partial_fn(descending)(&a.total_bytes, &b.total_bytes));
            }
            DiskWidgetColumn::IoRead => {
                data.sort_by(|a, b| sort_partial_fn(descending)(&a.io_read, &b.io_read));
            }
            DiskWidgetColumn::IoWrite => {
                data.sort_by(|a, b| sort_partial_fn(descending)(&a.io_write, &b.io_write));
            }
        }
    }
}

impl DiskTableWidget {
    pub fn new(config: &AppConfigFields, colours: &CanvasStyling) -> Self {
        let columns = [
            SortColumn::soft(DiskWidgetColumn::Disk, Some(0.2)),
            SortColumn::soft(DiskWidgetColumn::Mount, Some(0.2)),
            SortColumn::hard(DiskWidgetColumn::Used, 8).default_descending(),
            SortColumn::hard(DiskWidgetColumn::Free, 8).default_descending(),
            SortColumn::hard(DiskWidgetColumn::Total, 9).default_descending(),
            SortColumn::hard(DiskWidgetColumn::UsedPercent, 9).default_descending(),
            SortColumn::hard(DiskWidgetColumn::IoRead, 10).default_descending(),
            SortColumn::hard(DiskWidgetColumn::IoWrite, 11).default_descending(),
        ];

        let props = SortDataTableProps {
            inner: DataTableProps {
                title: Some(" Disks ".into()),
                table_gap: config.table_gap,
                left_to_right: true,
                is_basic: config.use_basic_mode,
                show_table_scroll_position: config.show_table_scroll_position,
                show_current_entry_when_unfocused: false,
            },
            sort_index: 0,
            order: SortOrder::Ascending,
        };

        let styling = DataTableStyling::from_colours(colours);

        Self {
            table: SortDataTable::new_sortable(columns, props, styling),
            force_update_data: false,
        }
    }

    /// Forces an update of the data stored.
    #[inline]
    pub fn force_data_update(&mut self) {
        self.force_update_data = true;
    }

    /// Update the current table data.
    pub fn set_table_data(&mut self, data: &[DiskWidgetData]) {
        let mut data = data.to_vec();
        if let Some(column) = self.table.columns.get(self.table.sort_index()) {
            column.sort_by(&mut data, self.table.order());
        }
        self.table.set_data(data);
    }

    pub fn set_index(&mut self, index: usize) {
        self.table.set_sort_index(index);
        self.force_data_update();
    }
}