use xcb::{
    x::{self, Atom, ChangeProperty, GetProperty, Gravity, Pixmap, PropMode, Window},
    Xid, XidNew,
};

use crate::conn_info::Connection;

/// EWM Hints set on a window.
pub struct Ewm {
    flags: u32,
    input: bool,
    initial_state: i32,
    icon_pixmap: Pixmap,
    icon_window: Window,
    icon_x: i32,
    icon_y: i32,
    icon_mask: Pixmap,
    window_group: u32,
}

impl Ewm {
    /// Get the EWM hints for the given window, if they exist and are valid.
    pub fn get(conn: &Connection<'_>, window: Window) -> Option<Self> {
        // https://github.com/mirror/libX11/blob/ff8706a5eae25b8bafce300527079f68a201d27f/src/GetHints.c#L106
        // https://github.com/mirror/libX11/blob/master/src/Xatomtype.h#L111
        let hints = conn
            .wait_for_reply(conn.send_request(&GetProperty {
                window,
                delete: false,
                property: x::ATOM_WM_HINTS,
                r#type: x::ATOM_WM_HINTS,
                long_offset: 0,
                long_length: 9,
            }))
            .ok()?;

        if hints.r#type() != x::ATOM_WM_HINTS || hints.length() < 8 || hints.format() != 32 {
            return None;
        }

        let [flags, input, initial_state, icon_pixmap, icon_window, icon_x, icon_y, icon_mask, window_group] =
            match hints.value::<u32>() {
                [f, i, is, ip, iw, ix, iy, im, wg] => [f, i, is, ip, iw, ix, iy, im, wg],
                [f, i, is, ip, iw, ix, iy, im] => [f, i, is, ip, iw, ix, iy, im, &0],
                _ => unreachable!(),
            };

        unsafe {
            Some(Self {
                flags: *flags,
                input: *input > 0,
                initial_state: std::mem::transmute::<u32, i32>(*initial_state),
                icon_pixmap: Pixmap::new(*icon_pixmap),
                icon_window: Window::new(*icon_window),
                icon_x: std::mem::transmute::<u32, i32>(*icon_x),
                icon_y: std::mem::transmute::<u32, i32>(*icon_y),
                icon_mask: Pixmap::new(*icon_mask),
                window_group: *window_group,
            })
        }
    }

    /// Set these WM hints on the given window.
    pub fn apply(&self, conn: &Connection<'_>, window: Window) {
        conn.send_request(&ChangeProperty {
            mode: PropMode::Replace,
            window,
            property: x::ATOM_WM_HINTS,
            r#type: x::ATOM_WM_HINTS,
            data: unsafe {
                &[
                    self.flags,
                    u32::from(self.input),
                    std::mem::transmute::<i32, u32>(self.initial_state),
                    self.icon_pixmap.resource_id(),
                    self.icon_window.resource_id(),
                    std::mem::transmute::<i32, u32>(self.icon_x),
                    std::mem::transmute::<i32, u32>(self.icon_y),
                    self.icon_mask.resource_id(),
                    self.window_group,
                ]
            },
        });
    }

    /// If the window is flagged as urgent
    pub const fn is_urgent(&self) -> bool {
        (self.flags & 1 << 8) > 0
    }

    /// Set the urgent flag. [`Self::apply`] should be called afterwards.
    pub fn set_urgent(&mut self, urgent: bool) {
        self.flags &= u32::from(urgent) << 8;
    }

    /// Whether the window has the `input` flag set, unset, or not specified.
    pub const fn input(&self) -> Option<bool> {
        if (self.flags & 1 << 0) > 0 {
            Some(self.input)
        } else {
            None
        }
    }
}

#[derive(Debug)]
pub struct Size {
    /// The minimum size this window needs to be useful (width, height).
    min_size: Option<(u32, u32)>,

    /// The maximum size at which this window can be useful (width, height).
    max_size: Option<(u32, u32)>,

    /// The increments in which to resize this window (width, height)
    resize_increments: Option<(u32, u32)>,

    /// The ideal base size of this window (width, height)
    base_size: Option<(u32, u32)>,

    /// What side of the screen to gravitate this window towards.
    win_gravity: Gravity,
}

impl Size {
    const PROGRAM_MIN_SIZE: u32 = (1 << 4);
    const PROGRAM_MAX_SIZE: u32 = (1 << 5);
    const PROGRAM_RESIZE_INC: u32 = (1 << 6);
    const PROGRAM_BASE_SIZE: u32 = (1 << 8);
    const PROGRAM_WIN_GRAVITY: u32 = (1 << 9);

    /// Get the size hints for the given window, if they exist and are valid.
    pub fn get(conn: &Connection<'_>, window: Window) -> Option<Self> {
        // https://github.com/mirror/libX11/blob/ff8706a5eae25b8bafce300527079f68a201d27f/src/GetHints.c#L59
        // https://github.com/mirror/libX11/blob/master/src/Xatomtype.h#L77
        let hints = conn
            .wait_for_reply(conn.send_request(&GetProperty {
                window,
                delete: false,
                property: x::ATOM_WM_NORMAL_HINTS,
                r#type: x::ATOM_WM_SIZE_HINTS,
                long_offset: 0,
                long_length: 18,
            }))
            .ok()?;

        if hints.r#type() != x::ATOM_WM_SIZE_HINTS || hints.length() < 18 || hints.format() != 32 {
            return None;
        }

        let &[flags, _, _, _, _, min_width, min_height, max_width, max_height, width_inc, height_inc, _, _, _, _, base_width, base_height, win_gravity] =
            hints.value::<u32>()
        else {
            unreachable!()
        };

        Some(Self {
            min_size: if (flags & Self::PROGRAM_MIN_SIZE) > 0 {
                Some((min_width, min_height))
            } else if (flags & Self::PROGRAM_BASE_SIZE) > 0 {
                Some((base_width, base_height))
            } else {
                None
            },
            max_size: if (flags & Self::PROGRAM_MAX_SIZE) > 0 {
                Some((max_width, max_height))
            } else {
                None
            },
            resize_increments: if (flags & Self::PROGRAM_RESIZE_INC) > 0 {
                Some((width_inc, height_inc))
            } else {
                None
            },
            base_size: if (flags & Self::PROGRAM_BASE_SIZE) > 0 {
                Some((base_width, base_height))
            } else if (flags & Self::PROGRAM_MIN_SIZE) > 0 {
                Some((min_width, min_height))
            } else {
                None
            },
            win_gravity: if (flags & Self::PROGRAM_WIN_GRAVITY) > 0 {
                match win_gravity {
                    2 => Gravity::North,
                    3 => Gravity::NorthEast,
                    4 => Gravity::West,
                    5 => Gravity::Center,
                    6 => Gravity::East,
                    7 => Gravity::SouthWest,
                    8 => Gravity::South,
                    9 => Gravity::SouthEast,
                    _ => Gravity::NorthWest,
                }
            } else {
                Gravity::NorthWest
            },
        })
    }
}

/// Gets the `WM_TRANSIENT_FOR` hint set on a window
pub fn transient_for(conn: &Connection, window: Window) -> Option<Window> {
    let hints = conn
        .wait_for_reply(conn.send_request(&GetProperty {
            window,
            delete: false,
            property: x::ATOM_WM_TRANSIENT_FOR,
            r#type: x::ATOM_WINDOW,
            long_offset: 0,
            long_length: 1,
        }))
        .ok()?;

    if hints.r#type() != x::ATOM_WINDOW || hints.length() < 1 || hints.format() != 32 {
        return None;
    }

    Some(hints.value::<Window>()[0])
}

/// Check if the given window is flagged as a dialog with the `NET_WM_WINDOW_TYPE` property
pub fn is_dialog(conn: &Connection, window: Window) -> bool {
    let Ok(hints) = conn.wait_for_reply(conn.send_request(&GetProperty {
        window,
        delete: false,
        property: conn.atoms.net_wm_window_type,
        r#type: x::ATOM_ATOM,
        long_offset: 0,
        long_length: 1,
    })) else {
        return false;
    };

    hints.r#type() == x::ATOM_ATOM
        && hints.length() == 1
        && hints.format() == 32
        && hints.value::<Atom>()[0] == conn.atoms.net_wm_window_type_dialog
}

/// Check if the given window wants to be fullscreen, using the `NET_WM_STATE` property
pub fn is_fullscreen(conn: &Connection, window: Window) -> bool {
    let Ok(hints) = conn.wait_for_reply(conn.send_request(&GetProperty {
        window,
        delete: false,
        property: conn.atoms.net_wm_state,
        r#type: x::ATOM_ATOM,
        long_offset: 0,
        long_length: 9999,
    })) else {
        return false;
    };

    hints.r#type() == x::ATOM_ATOM
        && hints.format() == 32
        && hints
            .value::<Atom>()
            .iter()
            .any(|a| *a == conn.atoms.net_wm_fullscreen)
}