use crate::{color::*, math::*, types::*};

#[derive(Clone, Copy, Debug, Serialize)]
pub struct Style {
    /// Horizontal and vertical padding within a window frame.
    pub window_padding: Vec2,

    /// Button size is text size plus this on each side
    pub button_padding: Vec2,

    /// Horizontal and vertical spacing between widgets
    pub item_spacing: Vec2,

    /// Indent foldable regions etc by this much.
    pub indent: f32,

    /// Anything clickable is (at least) this wide.
    pub clickable_diameter: f32,

    /// Checkboxes, radio button and foldables have an icon at the start.
    /// The text starts after this many pixels.
    pub start_icon_width: f32,

    // -----------------------------------------------
    // Purely visual:
    /// For stuff like check marks in check boxes.
    pub line_width: f32,

    pub window: Window,
}

#[derive(Clone, Copy, Debug, Serialize)]
pub struct Window {
    pub corner_radius: f32,
}

impl Default for Style {
    fn default() -> Self {
        Style {
            window_padding: vec2(6.0, 6.0),
            button_padding: vec2(5.0, 3.0),
            item_spacing: vec2(8.0, 4.0),
            indent: 21.0,
            clickable_diameter: 34.0,
            start_icon_width: 20.0,
            line_width: 1.0,
            window: Window::default(),
        }
    }
}

impl Default for Window {
    fn default() -> Self {
        Window {
            corner_radius: 10.0,
        }
    }
}

impl Style {
    /// e.g. the background of the slider
    pub fn background_fill_color(&self) -> Color {
        gray(34, 230)
    }

    pub fn text_color(&self) -> Color {
        gray(255, 200)
    }

    /// Fill color of the interactive part of a component (button, slider grab, checkbox, ...)
    pub fn interact_fill_color(&self, interact: &InteractInfo) -> Option<Color> {
        if interact.active {
            Some(srgba(100, 100, 200, 255))
        } else if interact.hovered {
            Some(srgba(100, 100, 150, 255))
        } else {
            Some(srgba(60, 60, 70, 255))
        }
    }

    /// Stroke and text color of the interactive part of a component (button, slider grab, checkbox, ...)
    pub fn interact_stroke_color(&self, interact: &InteractInfo) -> Color {
        if interact.active {
            gray(255, 255)
        } else if interact.hovered {
            gray(255, 200)
        } else {
            gray(255, 170)
        }
    }

    pub fn interact_stroke_width(&self, interact: &InteractInfo) -> f32 {
        if interact.active {
            2.0
        } else if interact.hovered {
            1.5
        } else {
            1.0
        }
    }

    pub fn interact_outline(&self, interact: &InteractInfo) -> Option<Outline> {
        Some(Outline::new(
            self.interact_stroke_width(interact),
            self.interact_stroke_color(interact),
        ))
    }

    /// Returns small icon rectangle and big icon rectangle
    pub fn icon_rectangles(&self, rect: &Rect) -> (Rect, Rect) {
        let box_side = 16.0;
        let big_icon_rect = Rect::from_center_size(
            pos2(rect.min().x + 4.0 + box_side * 0.5, rect.center().y),
            vec2(box_side, box_side),
        );

        let small_icon_rect = Rect::from_center_size(big_icon_rect.center(), vec2(10.0, 10.0));

        (small_icon_rect, big_icon_rect)
    }
}

impl Style {
    pub fn ui(&mut self, region: &mut crate::Region) {
        use crate::widgets::{Button, Slider};
        if region.add(Button::new("Reset style")).clicked {
            *self = Default::default();
        }
        region.add(Slider::f32(&mut self.item_spacing.x, 0.0, 10.0).text("item_spacing.x"));
        region.add(Slider::f32(&mut self.item_spacing.y, 0.0, 10.0).text("item_spacing.y"));
        region.add(Slider::f32(&mut self.window_padding.x, 0.0, 10.0).text("window_padding.x"));
        region.add(Slider::f32(&mut self.window_padding.y, 0.0, 10.0).text("window_padding.y"));
        region.add(Slider::f32(&mut self.indent, 0.0, 100.0).text("indent"));
        region.add(Slider::f32(&mut self.button_padding.x, 0.0, 20.0).text("button_padding.x"));
        region.add(Slider::f32(&mut self.button_padding.y, 0.0, 20.0).text("button_padding.y"));
        region.add(Slider::f32(&mut self.clickable_diameter, 0.0, 60.0).text("clickable_diameter"));
        region.add(Slider::f32(&mut self.start_icon_width, 0.0, 60.0).text("start_icon_width"));
        region.add(Slider::f32(&mut self.line_width, 0.0, 10.0).text("line_width"));
    }
}