From 3c0ea68d29e9e85797b9716005bf95d5e7d24c7d Mon Sep 17 00:00:00 2001
From: Joscha <joscha@plugh.de>
Date: Sun, 12 Dec 2021 11:09:14 +0000
Subject: [PATCH] Render layouts

---
 src/cli.rs        |   8 +-
 src/cli/render.rs | 226 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 232 insertions(+), 2 deletions(-)
 create mode 100644 src/cli/render.rs

diff --git a/src/cli.rs b/src/cli.rs
index aff5edf..b4a1273 100644
--- a/src/cli.rs
+++ b/src/cli.rs
@@ -7,8 +7,10 @@ use crate::eval::{DateRange, EntryMode};
 use crate::files::Files;
 
 use self::layout::Layout;
+use self::render::Render;
 
 mod layout;
+mod render;
 
 #[derive(Debug, StructOpt)]
 pub struct Opt {
@@ -29,11 +31,13 @@ pub fn run() -> anyhow::Result<()> {
     .unwrap();
 
     let entries = files.eval(EntryMode::Relevant, range)?;
-    println!("{:#?}", entries);
 
     let mut layout = Layout::new(range, now);
     layout.layout(&files, &entries);
-    println!("{:#?}", layout);
+
+    let mut render = Render::new();
+    render.render(&files, &entries, &layout);
+    print!("{}", render.display());
 
     files.save()?;
     Ok(())
diff --git a/src/cli/render.rs b/src/cli/render.rs
new file mode 100644
index 0000000..7f26500
--- /dev/null
+++ b/src/cli/render.rs
@@ -0,0 +1,226 @@
+use std::collections::HashMap;
+
+use crate::eval::{Entry, EntryKind};
+use crate::files::commands::Command;
+use crate::files::primitives::Time;
+use crate::files::Files;
+
+use super::layout::{Layout, LayoutEntry};
+
+#[derive(Debug, Clone, Copy)]
+enum SpanSegment {
+    Start,
+    Middle,
+    End,
+}
+
+struct Line {
+    number: Option<usize>,
+    spans: Vec<Option<SpanSegment>>,
+    time: Option<Time>,
+    text: String,
+}
+
+pub struct Render {
+    numbers: HashMap<usize, usize>,
+    last_number: usize,
+    spans: Vec<Option<(usize, SpanSegment)>>,
+    lines: Vec<Line>,
+}
+
+impl Render {
+    pub fn new() -> Self {
+        Self {
+            numbers: HashMap::new(),
+            last_number: 0,
+            spans: vec![],
+            lines: vec![],
+        }
+    }
+
+    pub fn render(&mut self, files: &Files, entries: &[Entry], layout: &Layout) {
+        // Make sure spans for visible `*End`s are drawn
+        for entry in &layout.earlier {
+            match entry {
+                LayoutEntry::TimedStart(i, _) | LayoutEntry::Start(i) => self.start_span(*i),
+                _ => {}
+            }
+        }
+        self.step_spans();
+
+        for day in layout.range.days() {
+            self.line(None, None, format!("{}", day));
+
+            let layout_entries = layout.days.get(&day).expect("got nonexisting day");
+            for layout_entry in layout_entries {
+                self.render_layout_entry(files, entries, layout_entry);
+            }
+        }
+    }
+
+    pub fn display(&self) -> String {
+        let mut result = String::new();
+
+        let num_width = format!("{}", self.last_number).len();
+        let span_width = self.spans.len();
+
+        for line in &self.lines {
+            let num = match line.number {
+                Some(n) => format!("{}", n),
+                None => "".to_string(),
+            };
+
+            let mut span = String::new();
+            for s in &line.spans {
+                span.push(match s {
+                    Some(SpanSegment::Start) => '┏',
+                    Some(SpanSegment::Middle) => '┃',
+                    Some(SpanSegment::End) => '┗',
+                    None => ' ',
+                })
+            }
+
+            let time = match line.time {
+                Some(t) => format!(" {}", t),
+                None => "".to_string(),
+            };
+
+            result.push_str(&format!(
+                "{:nw$} {:sw$}{} {}\n",
+                num,
+                span,
+                time,
+                line.text,
+                nw = num_width,
+                sw = span_width
+            ))
+        }
+
+        result
+    }
+
+    fn render_layout_entry(&mut self, files: &Files, entries: &[Entry], l_entry: &LayoutEntry) {
+        match l_entry {
+            LayoutEntry::End(i) => {
+                self.stop_span(*i);
+                self.line(Some(*i), None, Self::format_entry(files, entries, *i));
+            }
+            LayoutEntry::Now(t) => self.line(None, Some(*t), "now".to_string()),
+            LayoutEntry::TimedEnd(i, t) => {
+                self.stop_span(*i);
+                self.line(Some(*i), Some(*t), Self::format_entry(files, entries, *i));
+            }
+            LayoutEntry::TimedAt(i, t) => {
+                self.line(Some(*i), Some(*t), Self::format_entry(files, entries, *i));
+            }
+            LayoutEntry::TimedStart(i, t) => {
+                self.start_span(*i);
+                self.line(Some(*i), Some(*t), Self::format_entry(files, entries, *i));
+            }
+            LayoutEntry::ReminderSince(i, d) => {
+                let text = Self::format_entry(files, entries, *i);
+                let text = if *d == 1 {
+                    format!("{} (yesterday)", text)
+                } else {
+                    format!("{} ({} days ago)", text, d)
+                };
+                self.line(Some(*i), None, text);
+            }
+            LayoutEntry::At(i) => self.line(Some(*i), None, Self::format_entry(files, entries, *i)),
+            LayoutEntry::ReminderWhile(i, d) => {
+                let text = Self::format_entry(files, entries, *i);
+                let plural = if *d == 1 { "" } else { "s" };
+                let text = format!("{} ({} day{} left)", text, i, plural);
+                self.line(Some(*i), None, text);
+            }
+            LayoutEntry::Undated(i) => {
+                self.line(Some(*i), None, Self::format_entry(files, entries, *i));
+            }
+            LayoutEntry::Start(i) => {
+                self.start_span(*i);
+                self.line(Some(*i), None, Self::format_entry(files, entries, *i));
+            }
+            LayoutEntry::ReminderUntil(i, d) => {
+                let text = Self::format_entry(files, entries, *i);
+                let text = if *d == 1 {
+                    format!("{} (tomorrow)", text)
+                } else {
+                    format!("{} (in {} days)", text, d)
+                };
+                self.line(Some(*i), None, text);
+            }
+        }
+    }
+
+    fn format_entry(files: &Files, entries: &[Entry], index: usize) -> String {
+        let entry = entries[index];
+        let command = files.command(entry.source);
+        match entry.kind {
+            EntryKind::Task => format!("T {}", command.title()),
+            EntryKind::TaskDone(_) => format!("D {}", command.title()),
+            EntryKind::Note => format!("N {}", command.title()),
+            EntryKind::Birthday(Some(age)) => format!("B {} ({})", command.title(), age),
+            EntryKind::Birthday(None) => format!("B {}", command.title()),
+        }
+    }
+
+    fn start_span(&mut self, index: usize) {
+        for span in self.spans.iter_mut() {
+            if span.is_none() {
+                *span = Some((index, SpanSegment::Start));
+                return;
+            }
+        }
+
+        // Not enough space, we need another column
+        self.spans.push(Some((index, SpanSegment::Start)));
+    }
+
+    fn stop_span(&mut self, index: usize) {
+        for span in self.spans.iter_mut() {
+            match span {
+                Some((i, s)) if *i == index => *s = SpanSegment::End,
+                _ => {}
+            }
+        }
+    }
+
+    fn step_spans(&mut self) {
+        for span in self.spans.iter_mut() {
+            match span {
+                Some((_, s @ SpanSegment::Start)) => *s = SpanSegment::Middle,
+                Some((_, SpanSegment::End)) => *span = None,
+                _ => {}
+            }
+        }
+    }
+
+    fn line(&mut self, index: Option<usize>, time: Option<Time>, text: String) {
+        let number = match index {
+            Some(index) => Some(match self.numbers.get(&index) {
+                Some(number) => *number,
+                None => {
+                    self.last_number += 1;
+                    self.numbers.insert(index, self.last_number);
+                    self.last_number
+                }
+            }),
+            None => None,
+        };
+
+        let spans = self
+            .spans
+            .iter()
+            .map(|span| span.as_ref().map(|(_, s)| *s))
+            .collect();
+
+        self.lines.push(Line {
+            number,
+            spans,
+            time,
+            text,
+        });
+
+        self.step_spans();
+    }
+}