From 32901f57d2ab891d03377e097e1cba403efe4d33 Mon Sep 17 00:00:00 2001
From: Manos Pitsidianakis <el13635@mail.ntua.gr>
Date: Wed, 15 Sep 2021 22:19:19 +0300
Subject: [PATCH] Add show_date_in_my_timezone pager config flag

Closes #28
---
 docs/meli.conf.5            |  5 ++++
 src/components/mail/view.rs | 46 ++++++++++++++++++++++++++++++++++++-
 src/conf/overrides.rs       |  6 +++++
 src/conf/pager.rs           |  5 ++++
 4 files changed, 61 insertions(+), 1 deletion(-)

diff --git a/docs/meli.conf.5 b/docs/meli.conf.5
index 9e5b799d..5ee92dcd 100644
--- a/docs/meli.conf.5
+++ b/docs/meli.conf.5
@@ -880,6 +880,11 @@ Minimum text width in columns.
 Choose `text/html` alternative if `text/plain` is empty in `multipart/alternative` attachments.
 .\" default value
 .Pq Em true
+.It Ic show_date_in_my_timezone Ar boolean
+.Pq Em optional
+Show Date: in local timezone
+.\" default value
+.Pq Em true
 .El
 .Sh LISTING
 .Bl -tag -width 36n
diff --git a/src/components/mail/view.rs b/src/components/mail/view.rs
index a7931f7c..ee142d80 100644
--- a/src/components/mail/view.rs
+++ b/src/components/mail/view.rs
@@ -1111,8 +1111,52 @@ impl Component for MailView {
                         })+
                     };
                 }
+                let find_offset = |s: &str| -> (bool, (i64, i64)) {
+                    let mut diff = (true, (0, 0));
+                    if let Some(pos) = s.as_bytes().iter().position(|b| *b == b'+' || *b == b'-') {
+                        let offset = &s[pos..];
+                        diff.0 = offset.starts_with('+');
+                        if let (Ok(hr_offset), Ok(min_offset)) =
+                            (offset[1..3].parse::<i64>(), offset[3..5].parse::<i64>())
+                        {
+                            diff.1 .0 = hr_offset;
+                            diff.1 .1 = min_offset;
+                        }
+                    }
+                    diff
+                };
+                let orig_date = envelope.date_as_str();
+                let date_str: std::borrow::Cow<str> = if mailbox_settings!(
+                    context[self.coordinates.0][&self.coordinates.1]
+                        .pager
+                        .show_date_in_my_timezone
+                )
+                .is_true()
+                {
+                    let local_date = melib::datetime::timestamp_to_string(
+                        envelope.timestamp,
+                        Some(melib::datetime::RFC822_DATE),
+                        false,
+                    );
+                    let orig_offset = find_offset(orig_date);
+                    let local_offset = find_offset(&local_date);
+                    if orig_offset == local_offset {
+                        orig_date.into()
+                    } else {
+                        format!(
+                            "{} [actual timezone: {}{:02}{:02}]",
+                            local_date,
+                            if orig_offset.0 { '+' } else { '-' },
+                            orig_offset.1 .0,
+                            orig_offset.1 .1
+                        )
+                        .into()
+                    }
+                } else {
+                    orig_date.into()
+                };
                 print_header!(
-                    ("Date:", envelope.date_as_str()),
+                    ("Date:", date_str),
                     ("From:", envelope.field_from_to_string()),
                     ("To:", envelope.field_to_to_string()),
                 );
diff --git a/src/conf/overrides.rs b/src/conf/overrides.rs
index 7629178a..2b10540d 100644
--- a/src/conf/overrides.rs
+++ b/src/conf/overrides.rs
@@ -76,6 +76,11 @@ pub struct PagerSettingsOverride {
     #[serde(alias = "auto-choose-multipart-alternative")]
     #[serde(default)]
     pub auto_choose_multipart_alternative: Option<ToggleFlag>,
+    #[doc = " Show Date: in my timezone"]
+    #[doc = " Default: true"]
+    #[serde(alias = "show-date-in-my-timezone")]
+    #[serde(default)]
+    pub show_date_in_my_timezone: Option<ToggleFlag>,
 }
 impl Default for PagerSettingsOverride {
     fn default() -> Self {
@@ -90,6 +95,7 @@ impl Default for PagerSettingsOverride {
             split_long_lines: None,
             minimum_width: None,
             auto_choose_multipart_alternative: None,
+            show_date_in_my_timezone: None,
         }
     }
 }
diff --git a/src/conf/pager.rs b/src/conf/pager.rs
index 99754037..a76d6886 100644
--- a/src/conf/pager.rs
+++ b/src/conf/pager.rs
@@ -87,6 +87,10 @@ pub struct PagerSettings {
         alias = "auto-choose-multipart-alternative"
     )]
     pub auto_choose_multipart_alternative: ToggleFlag,
+    /// Show Date: in my timezone
+    /// Default: true
+    #[serde(default = "internal_value_true", alias = "show-date-in-my-timezone")]
+    pub show_date_in_my_timezone: ToggleFlag,
 }
 
 impl Default for PagerSettings {
@@ -102,6 +106,7 @@ impl Default for PagerSettings {
             split_long_lines: true,
             minimum_width: 80,
             auto_choose_multipart_alternative: ToggleFlag::InternalVal(true),
+            show_date_in_my_timezone: ToggleFlag::InternalVal(true),
         }
     }
 }