Refactor

* use std::date instead of plain integers and own functions
* add a drop down for view type (not functional)

Signed-off-by: Fabrizio Iannetti <fabrizio.iannetti@gmail.com>

src/calendar.rs

@@ -14,121 +14,93 @@ use iced_native::{Color, Element, Length, Point, Rectangle, Size, Widget};
 use iced_native::text;
 use iced_native::alignment;
 use iced_native::widget::Tree;
-use chrono::{NaiveDate, Datelike};
+use chrono::{NaiveDate, Datelike, Duration, Weekday, Local};
 
 //use std::cmp;
 
 //-------------------------------------------------------------------------
 
-const DAYS_PER_MONTH: [i32;12] = [
-    31, // jan
-    28, // feb
-    31, // mar
-    30, // apr
-    31, // may
-    30, // jun
-    31, // jul
-    31, // ago
-    30, // sep
-    31, // oct
-    30, // nov
-    31, // dec
-];
-
 #[derive(Clone)]
 pub struct CalendarParams {
-    weekday_on_first_of_january: i32, // 0 -> Monday .. 6 -> Sunday
+    show_weeks: bool,
-    first_week_on_first_of_january: bool,
-    leap_year: bool,
-}
-
-impl CalendarParams {
-    pub fn new() -> Self {
-        // temp: data for 2022
-        Self {
-            weekday_on_first_of_january: 5, // saturday
-            first_week_on_first_of_january: false,
-            leap_year: false
-        }
-    }
-
-    pub fn day_first_of_month(&self, month: i32) -> i32 {
-        let mut day : i32 = 0;
-        for i in 0..month {
-            day += DAYS_PER_MONTH[i as usize];
-            if i == 1 && self.leap_year {
-                day += 1;
-            }
-        }
-        day
-    }
-
-    pub fn monthday(&self, month: i32, day: i32) -> i32 {
-        let mut month_days: i32 = DAYS_PER_MONTH[month as usize];
-        let mut month: i32 = month;
-        let mut day: i32 = day;
-        while day < 0 || day >= month_days {
-            if day < 0 {
-                month = (month + 12 - 1) % 12;
-                day = day + DAYS_PER_MONTH[month as usize];
-            } else {
-                day = day - DAYS_PER_MONTH[month as usize];
-                month = (month + 1) % 12;
-            }
-            month_days = DAYS_PER_MONTH[month as usize];
-        }
-        day
-    }
-
-    pub fn weekday(&self, month: i32, day: i32) -> i32 {
-        let day = self.day_first_of_month(month) + day;
-        (self.weekday_on_first_of_january + day) % 7
-    }
-
-    pub fn weekday_first_of_month(&self, month: i32) -> i32 {
-        self.weekday(month, 0)
-    }
-}
-//-------------------------------------------------------------------------
-
-pub struct CalendarMonthView {
-    first_day: NaiveDate,
-    month: i32,
-    params: CalendarParams,
-    weekday_on_first: i32, // 0 -> Monday .. 6 -> Sunday
     header_fg: Color,
     header_bg: Color,
     day_text: Color,
     day_text_other_month: Color,
     day_weekend_bg: Color,
+    day_today_bg: Color,
     day_text_margin: f32,
+}
+
+impl CalendarParams {
+    pub fn new() -> Self {
+        Self {
+            show_weeks: true,
+            header_fg: Color::BLACK,
+            header_bg: Color::TRANSPARENT,
+            day_today_bg: Color::from_rgb8(214, 242, 252),
+            day_text: Color::BLACK,
+            day_text_other_month: Color::from_rgb8(220, 220, 220),
+//            day_background: Color::from_rgb8(230, 230, 255),
+            day_weekend_bg: Color::from_rgb8(245, 245, 245),
+            day_text_margin: 5.0,
+        }
+    }
+}
+
+//-------------------------------------------------------------------------
+
+pub struct CalendarMonthView {
+    first_day: NaiveDate,
+    first_day_in_view: NaiveDate,
+    params: CalendarParams,
+    weekday_on_first: Weekday,
     week_column_width: f32,
     week_column_font_size: f32,
 }
 
 impl CalendarMonthView {
-    pub fn new(params: &CalendarParams, first_day: NaiveDate) -> Self {
+    pub fn new(params: &CalendarParams, day: NaiveDate) -> Self {
-        let month: i32 = first_day.month0() as i32;
+        // first day of the month
+        let first_day = if day.day() == 1 {
+            day
+        } else {
+            NaiveDate::from_ymd(day.year(), day.month(), 1)
+        };
+        
+        // weekday on first day of the month
+        let weekday_on_first = first_day.weekday();
+
+        // first visible day in the view
+        let first_day_in_view = first_day - Duration::days(weekday_on_first.num_days_from_monday() as i64);
+
         Self {
             first_day,
-            month,
+            first_day_in_view,
             params: params.clone(),
-            weekday_on_first: params.weekday_first_of_month(month), 
+            weekday_on_first, 
-            header_fg: Color::BLACK,
-            header_bg: Color::from_rgb8(214, 242, 252),
-            day_text: Color::BLACK,
-            day_text_other_month: Color::from_rgb8(220, 220, 220),
-//            day_background: Color::from_rgb8(230, 230, 255),
-            day_weekend_bg: Color::from_rgb8(230, 230, 230),
-            day_text_margin: 5.0,
             week_column_width: 30.0,
             week_column_font_size: 18.0,
         }
     }
 
-    pub fn set_month(&mut self, month: i32) {
+    pub fn set_month(&mut self, day: NaiveDate) {
-        self.month = month;
+        // first day of the month
-        self.weekday_on_first = self.params.weekday_first_of_month(month);
+        let first_day = if day.day() == 1 {
+            day
+        } else {
+            NaiveDate::from_ymd(day.year(), day.month(), 1)
+        };
+        
+        // weekday on first day of the month
+        let weekday_on_first = first_day.weekday();
+
+        // first visible day in the view
+        let first_day_in_view = first_day - Duration::days(weekday_on_first.num_days_from_monday() as i64);
+
+        self.first_day = first_day;
+        self.weekday_on_first = weekday_on_first;
+        self.first_day_in_view = first_day_in_view;
     }
 
     fn draw_header(
@@ -138,13 +110,15 @@ impl CalendarMonthView {
         week_w: f32,
     ) {
         // paint background over full width
-        renderer.fill_quad(renderer::Quad {
+        if self.params.header_bg != Color::TRANSPARENT {
-                bounds,
+            renderer.fill_quad(renderer::Quad {
-                border_radius: 0.0,
+                    bounds,
-                border_width: 0.0,
+                    border_radius: 0.0,
-                border_color: Color::TRANSPARENT,
+                    border_width: 0.0,
-            }, 
+                    border_color: Color::TRANSPARENT,
-            self.header_bg);
+                }, 
+                self.params.header_bg);
+        }
         
         // redefine bounds to skip the week column
         let bounds = Rectangle {
@@ -176,9 +150,9 @@ impl CalendarMonthView {
             let t =  days_of_week[weekday as usize];
 
             // color of text
-            let fg = self.header_fg;
+            let fg = self.params.header_fg;
 
-            let x = bounds.x + self.day_text_margin;
+            let x = bounds.x + self.params.day_text_margin;
             let y = bounds.center_y();
             renderer.fill_text(text::Text {
                 content : t,
@@ -205,34 +179,30 @@ impl CalendarMonthView {
             h
         } / 2.0;
 
-        for week in 0..6i32 {
+        let mut day = self.first_day;
+
+        for week in 0..6u32 {
             // where to place the week number
             let day_bounds = Rectangle { 
                 x: bounds.x, 
-                y: (week as f32) * h + bounds.y + self.day_text_margin, 
+                y: (week as f32) * h + bounds.y + self.params.day_text_margin, 
                 width: r * 2.0, 
                 height: r * 2.0 
             };
 
-            // paint the background as weekend (inactive)
+            let week_of_first_day_of_month = day.iso_week().week();
-//            renderer.fill_quad(renderer::Quad {
+            day += Duration::weeks(1);
-//                    bounds: day_bounds,
+
-//                    border_radius: r,
-//                    border_width: 0.0,
-//                    border_color: Color::TRANSPARENT,
-//                }, 
-//                self.day_weekend_bg);
-//
             // render week cell text
             renderer.fill_text(text::Text {
-                content : &week.to_string(),
+                content : &(week_of_first_day_of_month).to_string(),
                 size: self.week_column_font_size,
                 bounds: Rectangle {
                         x: day_bounds.center_x(),
                         y: day_bounds.y,
                         ..day_bounds
                     },
-                color: self.day_text,
+                color: self.params.day_text,
                 font: Default::default(),
                 horizontal_alignment: alignment::Horizontal::Center,
                 vertical_alignment: alignment::Vertical::Top,
@@ -255,25 +225,9 @@ impl CalendarMonthView {
         let w: f32 = size.width / 7.0;
         let h: f32 = size.height / 6.0;
 
-        let days_of_month = [
+        let mut current_day = self.first_day_in_view;
-            " 1", " 2", " 3", " 4", " 5", " 6", " 7", " 8", " 9", "10",
-            "11", "12", "13", "14", "15", "16", "17", "18", "19", "20",
-            "21", "22", "23", "24", "25", "26", "27", "28", "29", "30",
-            "31",
-            ];
-
-        // paint the background of the last two columns as weekend
-        renderer.fill_quad(renderer::Quad {
-                bounds: Rectangle {x: 5.0 * w + origin.x, y: origin.y, width: 2.0 * w, height: 6.0 * h},
-                border_radius: 0.0,
-                border_width: 0.0,
-                border_color: Color::TRANSPARENT,
-            }, 
-            self.day_weekend_bg);
-
         for week in 0..6i32 {
             for weekday in 0..7i32 {
-                let monthday = weekday + week * 7 - self.weekday_on_first;
                 let day_bounds = Rectangle { 
                     x: (weekday as f32) * w + origin.x, 
                     y: (week as f32) * h + origin.y, 
@@ -282,30 +236,40 @@ impl CalendarMonthView {
                 };
                         
                 // label (day letter on row 0, day number on the rest)
-                let t = days_of_month[self.params.monthday(self.month, monthday) as usize];
+                let t = current_day.day().to_string();
+                let content = t.as_str();
 
                 // color of text
-                let fg = if monthday >= 0 && monthday <= 30 {
+                let fg = if current_day.month() == self.first_day.month() {
-                    self.day_text
+                    self.params.day_text
                 } else {
-                    self.day_text_other_month
+                    self.params.day_text_other_month
+                };
+
+                // background color of the day cell
+                let bg_color = if current_day == Local::today().naive_local() {
+                    self.params.day_today_bg
+                } else if weekday > 4 {
+                    self.params.day_weekend_bg
+                } else {
+                    Color::TRANSPARENT
                 };
 
                 // where to place the day content
-                let x = day_bounds.x + self.day_text_margin;
+                let x = day_bounds.x + self.params.day_text_margin;
-                let y = day_bounds.y + self.day_text_margin;
+                let y = day_bounds.y + self.params.day_text_margin;
 
                 renderer.fill_quad(renderer::Quad {
-                        bounds: day_bounds,
+                        bounds: Rectangle {width: day_bounds.width + 0.5, height: day_bounds.height + 0.5, ..day_bounds},
                         border_radius: 0.0,
-                        border_width: 0.0,
+                        border_width: 1.0,
-                        border_color: self.day_text_other_month,
+                        border_color: self.params.day_text_other_month,
                     }, 
-                    Color::WHITE);
+                    bg_color);
 
                 // render day cell text
                 renderer.fill_text(text::Text {
-                    content : t,
+                    content,
                     size: font_size,
                     bounds: Rectangle {x, y, ..day_bounds},
                     color: fg,
@@ -313,6 +277,7 @@ impl CalendarMonthView {
                     horizontal_alignment: alignment::Horizontal::Left,
                     vertical_alignment: alignment::Vertical::Top,
                     });
+                current_day = current_day.succ();
             }
         }
     }
@@ -354,7 +319,7 @@ where
         let margin: f32 = 20.0;
 
         // week column only visible if there is enough space
-        let week_w = if size.width > self.week_column_width {
+        let week_w = if self.params.show_weeks && size.width > self.week_column_width {
             self.week_column_width
         } else {
             0.0

src/main.rs

@@ -12,6 +12,7 @@ use iced::widget::{
     Column, Row,
     Container,
     Button, Text,
+    pick_list,
 };
 //use iced::button;
 use iced::theme;
@@ -30,18 +31,57 @@ struct CalendarApp {
 enum Message {
     NextMonth,
     PrevMonth,
+    ViewModeSelected(ViewMode),
 }
 
-#[derive(Default)]
+//#[derive(Default)]
 struct Controls {
+    mode: Option<ViewMode>,
 }
 
+impl Default for Controls {
+    fn default() -> Controls {
+        Controls {
+            mode : Some(ViewMode::Month)
+        }
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum ViewMode {
+    Month,
+    Year,
+    Day,
+}
+
+impl std::fmt::Display for ViewMode {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(
+            f,
+            "{}",
+            match self {
+                ViewMode::Month => "Month",
+                ViewMode::Year => "Year",
+                ViewMode::Day => "Day",
+            }
+        )
+    }
+}
 impl Controls {
-    fn view(&self, month_name: &str) -> Element<Message> {
+    const MODES : [ViewMode; 3] = [ViewMode::Month, ViewMode::Year, ViewMode::Day];
+
+    fn view<'a>(&'a self, month_name: &'a str, year: i32) -> Element<Message> {
         Row::new()
             .align_items(Alignment::Center)
             .padding(5)
             .spacing(10)
+            .push(
+                pick_list(
+                &Controls::MODES[..],
+                self.mode,
+                Message::ViewModeSelected,
+                ).placeholder("mode")
+            )
             .push(
                 Button::new(Text::new("<"))
                 .on_press(Message::PrevMonth)
@@ -59,7 +99,7 @@ impl Controls {
                     .size(40),
             )
             .push(
-                Text::new("2022")
+                Text::new(year.to_string())
                     .width(Length::Fill)
                     .horizontal_alignment(iced_native::alignment::Horizontal::Right)
                     .size(40),
@@ -91,8 +131,11 @@ impl Sandbox for CalendarApp {
             Message::NextMonth => {
                 self.month = self.month + Months::new(1);
             }
+            Message::ViewModeSelected(mode) => {
+                self.controls.mode = Some(mode);
+            }
         }
-        println!("month={}", self.month);
+        //println!("month={}", self.month);
     }
 
     fn view(&self) -> Element<Message> {
@@ -112,7 +155,7 @@ impl Sandbox for CalendarApp {
         ];
         let content = Column::new()
             .align_items(Alignment::Fill)
-            .push(self.controls.view(MONTH_NAMES[self.month.month() as usize]))
+            .push(self.controls.view(MONTH_NAMES[self.month.month0() as usize], self.month.year()))
             .push(CalendarMonthView::new(&CalendarParams::new(), self.month))
             ;