usaidwat 4.0.0

// SPDX-License-Identifier: Apache-2.0
// Copyright (C) 2025 Michael Dippery <michael@monkey-robot.com>

//! Formats viewable objects for display in a terminal.

use crate::cli::DateFormat;
use crate::count::SubredditCount;
use crate::reddit::client::{Redditor, Timeline};
use crate::reddit::thing::{Comment, HasSubreddit, Submission};
use crate::text::RegexReplaceable;
use colored::Colorize;
use horologe::{Clock, age::HasAge};
use indoc::formatdoc;
use itertools::Itertools;

/// View renderer options.
///
/// `ViewOptions` follows a builder pattern, allowing callers to incrementally
/// build up a set of options from a default set, starting with [`ViewOptions::default()`].
///
/// # Examples
///
/// ```
/// use usaidwat::cli::DateFormat;
/// use usaidwat::view::ViewOptions;
/// let opts = ViewOptions::default().date_format(DateFormat::Relative).raw(true);
/// ```
#[derive(Debug, Default)]
pub struct ViewOptions {
    date_format: DateFormat,
    oneline: bool,
    grep: Option<String>,
    #[allow(dead_code)] // This will be used eventually
    raw: bool,
}

impl ViewOptions {
    /// Sets the date format option to relative or absolute.
    pub fn date_format(self, date_format: DateFormat) -> Self {
        Self {
            date_format,
            ..self
        }
    }

    /// Sets the "oneline" option to true or false.
    pub fn oneline(self, oneline: bool) -> Self {
        Self { oneline, ..self }
    }

    /// Sets the "grep" option.
    pub fn grep(self, grep: Option<String>) -> Self {
        Self { grep, ..self }
    }

    /// Sets the "raw" option to true or false.
    pub fn raw(self, raw: bool) -> Self {
        Self { raw, ..self }
    }
}

/// Something that has a date that can be formatted.
trait DateFormattable: HasAge {
    /// Formats the date associated with the data structure.
    ///
    /// The date format can be relative or absolute and is specified in the
    /// `ViewOptions` parameter.
    fn format_date<C: Clock>(&self, opts: &ViewOptions, clock: &C) -> String {
        match opts.date_format {
            DateFormat::Relative => self.relative_age(clock),
            DateFormat::Absolute => self.format_absolute_date(),
        }
    }

    /// Formats an absolute date associated with the data structure.
    fn format_absolute_date(&self) -> String {
        let date = self.created_local();
        let date_part = format!("{}", date.format("%a, %-d %b %Y"));
        let time_part = format!("{}", date.format("%l:%M %p"));
        // %l formats a single-digit time as, e.g., " 8",
        // but I want to trim off the leading space.
        let time_part = time_part.trim();
        format!("{date_part}, {time_part}")
    }
}

/// Marks an item that can be converted into a string for display on a terminal.
pub trait Viewable {
    /// Converts the item into a string for display on a terminal.
    ///
    /// `opts` are a set of view options that control formatting of the
    /// resulting string. `clock` is a source from which the current
    /// time can be derived for items that print their age or other
    /// time-based parameters.
    fn view<C: Clock>(&self, opts: &ViewOptions, clock: &C) -> String;
}

impl Viewable for Redditor {
    fn view<C: Clock>(&self, _: &ViewOptions, clock: &C) -> String {
        formatdoc! {"
            Created: {} ({})
            Link Karma: {}
            Comment Karma: {}",
            self.created_local().format("%b %d, %Y %H:%M %p"),
            self.relative_age(clock),
            self.link_karma(),
            self.comment_karma(),
        }
    }
}

impl Viewable for Comment {
    fn view<C: Clock>(&self, opts: &ViewOptions, clock: &C) -> String {
        if opts.oneline {
            self.view_oneline(opts, clock)
        } else {
            self.view_full(opts, clock)
        }
    }
}

impl DateFormattable for Comment {}

impl Comment {
    fn view_full<C: Clock>(&self, opts: &ViewOptions, clock: &C) -> String {
        let age = self.format_date(opts, clock);

        let body = if opts.raw {
            self.raw_body()
        } else {
            self.body()
        };

        let body = if !opts.raw
            && let Some(grep) = &opts.grep
        {
            body.replace_all(&format!("(?i)(?<s>{grep})"), &"$s".red().to_string())
        } else {
            body
        };

        formatdoc! {"
            {}
            {}
            {}
            {} {} {}

            {body}",
            self.subreddit().green(),
            self.permalink().yellow(),
            self.link_title().magenta(),
            age.blue(),
            "\u{2022}".cyan(),
            format!("{:+}", self.score()).blue(),
        }
    }

    fn view_oneline<C: Clock>(&self, _: &ViewOptions, _: &C) -> String {
        format!("{} {}", self.subreddit().green(), self.link_title())
    }
}

impl Viewable for Submission {
    fn view<C: Clock>(&self, opts: &ViewOptions, clock: &C) -> String {
        if opts.oneline {
            self.view_oneline()
        } else {
            self.view_full(opts, clock)
        }
    }
}

impl DateFormattable for Submission {}

impl Submission {
    fn view_full<C: Clock>(&self, opts: &ViewOptions, clock: &C) -> String {
        let age = self.format_date(opts, clock);
        String::from(
            formatdoc! {"
                {}
                {}
                {}
                {}
                {}",
                self.subreddit().green(),
                self.short_permalink().yellow(),
                self.title().magenta(),
                age.blue(),
                self.link_uri(),
            }
            // Remove trailing space since the link will be blank for self posts
            .trim_end(),
        )
    }

    fn view_oneline(&self) -> String {
        format!("{} {}", self.subreddit().green(), self.title())
    }

    fn short_permalink(&self) -> String {
        let permalink = self.permalink();
        let parts: Vec<_> = permalink.split("/").collect();
        let len = parts.len().saturating_sub(2);
        parts[..len].join("/")
    }

    fn link_uri(&self) -> &str {
        if self.is_self() { "" } else { self.url() }
    }
}

impl Viewable for Vec<SubredditCount> {
    fn view<C: Clock>(&self, _: &ViewOptions, _: &C) -> String {
        let width = self
            .iter()
            .map(|(subreddit, _)| subreddit.len())
            .max()
            .unwrap_or(0);

        self.iter()
            .map(|(subreddit, count)| format!("{subreddit:width$}  {count:>3}"))
            .join("\n")
    }
}

impl Viewable for Timeline {
    fn view<C: Clock>(&self, _: &ViewOptions, _: &C) -> String {
        let mut s = String::from(" ");
        s += (0..24)
            .map(|i| format!("{i:>3}"))
            .collect::<Vec<_>>()
            .join("")
            .as_ref();
        s += "\n";
        s += self
            .days()
            .map(|(wday, day)| {
                let wday = format!("{wday}")
                    .chars()
                    .nth(0)
                    .expect(&format!("could not get first character of {wday}"));
                let days = day
                    // Remove this line to print the number of comments instead of a *
                    .map(|d| if d > 0 { '*' } else { ' ' })
                    .map(|ch| format!("{ch:>3}"))
                    .join("");
                format!("{wday}{days}")
            })
            .collect::<Vec<_>>()
            .join("\n")
            .as_ref();
        s
    }
}

#[cfg(test)]
mod tests {
    fn with_no_color<F, T>(f: F) -> T
    where
        F: FnOnce() -> T,
    {
        colored::control::set_override(false);
        let result = f();
        colored::control::unset_override();
        result
    }

    mod view_options {
        use super::super::*;

        #[test]
        fn it_returns_default_options() {
            let opts = ViewOptions::default();
            assert_eq!(opts.date_format, DateFormat::default());
            assert!(!opts.oneline);
            assert!(!opts.raw);
        }

        #[test]
        fn it_returns_custom_options() {
            let opts = ViewOptions::default()
                .oneline(true)
                .raw(true)
                .date_format(DateFormat::Absolute);
            assert_eq!(opts.date_format, DateFormat::Absolute);
            assert!(opts.oneline);
            assert!(opts.raw);
        }

        #[test]
        fn it_returns_custom_options_with_only_oneline() {
            let opts = ViewOptions::default().oneline(true);
            assert_eq!(opts.date_format, DateFormat::default());
            assert!(opts.oneline);
            assert!(!opts.raw);
        }

        #[test]
        fn it_returns_custom_options_with_only_raw() {
            let opts = ViewOptions::default().raw(true);
            assert_eq!(opts.date_format, DateFormat::default());
            assert!(!opts.oneline);
            assert!(opts.raw);
        }
    }

    mod format_info {
        use super::super::*;
        use crate::reddit::Redditor;
        use crate::test_utils::load_output;
        use horologe::testing::FrozenClock;

        #[tokio::test]
        async fn it_formats_a_user() {
            let user = Redditor::test().await;
            let actual = user.view(&ViewOptions::default(), &FrozenClock::default());
            let expected = load_output("about_mipadi");
            assert_eq!(actual, expected);
        }
    }

    mod format_comment {
        use super::super::*;
        use super::with_no_color;
        use crate::reddit::Redditor;
        use crate::test_utils::{do_logging, load_output};
        use horologe::testing::FrozenClock;
        use pretty_assertions::assert_eq;

        // TODO: Test with and without color when possible

        async fn get_comment(n: usize) -> Comment {
            Redditor::test()
                .await
                .comments()
                .nth(n)
                .expect("no comment found")
        }

        #[tokio::test]
        async fn it_formats_an_absolute_date() {
            let actual = get_comment(0).await.format_absolute_date();
            let expected = "Thu, 17 Apr 2025, 8:44 PM";
            assert_eq!(actual, expected);
        }

        #[tokio::test]
        async fn it_formats_a_comment_with_a_raw_body() {
            let opts = ViewOptions::default().raw(true);
            let comment = get_comment(1).await;
            let actual = comment.view(&opts, &FrozenClock::default());
            let expected = load_output("comments_raw_body");
            assert_eq!(actual, expected, "\nleft:\n{actual}\n\nright:\n{expected}");
        }

        #[tokio::test]
        async fn it_formats_a_comment_with_markdown_markup() {
            let opts = ViewOptions::default();
            let comment = get_comment(3).await;
            let actual = comment.view(&opts, &FrozenClock::default());
            let expected = load_output("comments_markdown_body");
            assert_eq!(actual, expected, "\nleft:\n{actual}\n\nright:\n{expected}");
        }

        #[tokio::test]
        async fn it_formats_a_comment_with_no_markdown_markup() {
            do_logging();
            let opts = ViewOptions::default();
            let comment = get_comment(0).await;
            let actual = comment.view(&opts, &FrozenClock::default());
            let expected = load_output("comments_no_markdown");
            assert_eq!(actual, expected, "\nleft:\n{actual}\n\nright:\n{expected}");
        }

        #[tokio::test]
        async fn it_formats_a_comment_with_relative_dates() {
            do_logging();
            let opts = ViewOptions::default().date_format(DateFormat::Relative);
            let actual = get_comment(0).await.view(&opts, &FrozenClock::default());
            let expected = load_output("comments_relative_dates");
            assert_eq!(actual, expected, "\nleft:\n{actual}\n\nright:\n{expected}");
        }

        #[tokio::test]
        async fn it_formats_a_comment_with_absolute_dates() {
            do_logging();
            let opts = ViewOptions::default().date_format(DateFormat::Absolute);
            let actual = get_comment(0).await.view(&opts, &FrozenClock::default());
            let expected = load_output("comments_absolute_dates");
            assert_eq!(actual, expected, "\nleft:\n{actual}\n\nright:\n{expected}");
        }

        #[tokio::test]
        async fn it_formats_a_comment_on_oneline() {
            let opts = ViewOptions::default().oneline(true);
            let actual = get_comment(0).await.view(&opts, &FrozenClock::default());
            let expected = "\u{1b}[32mcyphersystem\u{1b}[0m Cypher System & ChatGPT";
            assert_eq!(actual, expected);
        }

        #[tokio::test]
        async fn it_formats_a_comment_with_grep() {
            let opts = ViewOptions::default().grep(Some(String::from("Pathfinder")));
            let actual = get_comment(3).await.view(&opts, &FrozenClock::default());
            let expected = load_output("comments_markdown_body_grep");
            assert_eq!(actual, expected);
        }

        #[tokio::test]
        async fn it_formats_a_comment_with_grep_case_insensitively() {
            let opts = ViewOptions::default().grep(Some(String::from("pathfinder")));
            let actual = get_comment(3).await.view(&opts, &FrozenClock::default());
            let expected = load_output("comments_markdown_body_grep");
            assert_eq!(actual, expected);
        }

        #[tokio::test]
        // TODO: Fix test
        // Running this causes the previous test to fail. I suspect tests are run
        // in parallel and colored::control::set_override() is not threadsafe.
        // Don't worry about this for now, but we should test uncolored output
        // eventually.
        #[ignore]
        async fn it_formats_a_comment_on_oneline_without_color() {
            let opts = ViewOptions::default().oneline(true);
            let expected = "cyphersystem Cypher System & ChatGPT";
            let comment = get_comment(0).await;
            let actual = with_no_color(|| comment.view(&opts, &FrozenClock::default()));
            assert_eq!(actual, expected);
        }
    }

    mod format_submission {
        use super::super::*;
        use crate::reddit::{Redditor, thing::Submission};
        use crate::test_utils::load_output;
        use horologe::testing::FrozenClock;
        use pretty_assertions::assert_eq;

        async fn get_post(n: usize) -> Submission {
            Redditor::test()
                .await
                .submissions()
                .nth(n)
                .expect("no comment found")
        }

        #[tokio::test]
        async fn it_returns_the_permalink_without_the_full_title() {
            let post = get_post(0).await;
            let expected = "https://www.reddit.com/r/rpg/comments/1hv9k9l";
            assert_eq!(post.short_permalink(), expected);
        }

        #[tokio::test]
        async fn it_returns_the_link_uri() {
            let post = get_post(0).await;
            let expected = "https://acoup.blog/2025/01/03/collections-coinage-and-the-tyranny-of-fantasy-gold/";
            assert_eq!(post.link_uri(), expected);
        }

        #[tokio::test]
        async fn it_returns_an_empty_link_uri_for_self_posts() {
            let post = get_post(3).await;
            assert_eq!(post.link_uri(), "")
        }

        #[tokio::test]
        async fn it_formats_a_post_with_relative_dates() {
            let post = get_post(0).await;
            let expected = load_output("posts");
            let actual = post.view(&ViewOptions::default(), &FrozenClock::default());
            assert_eq!(actual, expected);
        }

        #[tokio::test]
        async fn it_formats_a_post_with_absolute_dates() {
            let opts = ViewOptions::default().date_format(DateFormat::Absolute);
            let post = get_post(0).await;
            let expected = load_output("posts_absolute_dates");
            let actual = post.view(&opts, &FrozenClock::default());
            assert_eq!(actual, expected);
        }

        #[tokio::test]
        async fn it_formats_a_self_post() {
            let post = get_post(3).await;
            let expected = load_output("posts_self");
            let actual = post.view(&ViewOptions::default(), &FrozenClock::default());
            assert_eq!(actual, expected);
        }

        #[tokio::test]
        async fn it_formats_a_post_on_oneline() {
            let opts = ViewOptions::default().oneline(true);
            let post = get_post(0).await;
            let expected =
                "\u{1b}[32mrpg\u{1b}[0m Collections: Coinage and the Tyranny of Fantasy \"Gold\"";
            let actual = post.view(&opts, &FrozenClock::default());
            assert_eq!(actual, expected);
        }
    }

    mod format_tallies {
        use super::super::*;
        use crate::count::{SortAlgorithm, SubredditCounter};
        use crate::reddit::Redditor;
        use crate::test_utils::load_output;
        use horologe::testing::FrozenClock;
        use pretty_assertions::assert_eq;

        #[tokio::test]
        async fn it_formats_comment_tallies_by_subreddit_name() {
            let redditor = Redditor::test().await;
            let counts = SubredditCounter::from_iter(redditor.comments())
                .sort_by(&SortAlgorithm::Lexicographically);
            let expected = load_output("tally_comments_abc");
            let actual = counts.view(&ViewOptions::default(), &FrozenClock::default());
            assert_eq!(actual, expected);
        }

        #[tokio::test]
        async fn it_formats_comment_tallies_by_count() {
            let redditor = Redditor::test().await;
            let counts = SubredditCounter::from_iter(redditor.comments())
                .sort_by(&SortAlgorithm::Numerically);
            let expected = load_output("tally_comments_count");
            let actual = counts.view(&ViewOptions::default(), &FrozenClock::default());
            assert_eq!(actual, expected);
        }

        #[tokio::test]
        async fn it_returns_an_empty_string_if_no_comments() {
            let redditor = Redditor::test_empty().await;
            let counts =
                SubredditCounter::from_iter(redditor.comments()).sort_by(&SortAlgorithm::default());
            let actual = counts.view(&ViewOptions::default(), &FrozenClock::default());
            assert_eq!(actual, "");
        }

        #[tokio::test]
        async fn it_formats_submission_tallies_by_subreddit_name() {
            let redditor = Redditor::test().await;
            let counts = SubredditCounter::from_iter(redditor.submissions())
                .sort_by(&SortAlgorithm::Lexicographically);
            let expected = load_output("tally_posts_abc");
            let actual = counts.view(&ViewOptions::default(), &FrozenClock::default());
            assert_eq!(actual, expected);
        }

        #[tokio::test]
        async fn it_formats_submission_tallies_by_count() {
            let redditor = Redditor::test().await;
            let counts = SubredditCounter::from_iter(redditor.submissions())
                .sort_by(&SortAlgorithm::Numerically);
            let expected = load_output("tally_posts_count");
            let actual = counts.view(&ViewOptions::default(), &FrozenClock::default());
            assert_eq!(actual, expected);
        }

        #[tokio::test]
        async fn it_returns_an_empty_string_if_no_submissions() {
            let redditor = Redditor::test_empty().await;
            let counts = SubredditCounter::from_iter(redditor.submissions())
                .sort_by(&SortAlgorithm::default());
            let actual = counts.view(&ViewOptions::default(), &FrozenClock::default());
            assert_eq!(actual, "");
        }
    }

    mod format_timeline {
        use super::super::*;
        use crate::reddit::Redditor;
        use crate::test_utils::load_output;
        use horologe::testing::FrozenClock;

        #[tokio::test]
        async fn it_formats_a_timeline() {
            let user = Redditor::test().await;
            let actual = user
                .timeline()
                .view(&ViewOptions::default(), &FrozenClock::default());
            let expected = load_output("timeline_mipadi");
            assert_eq!(actual, expected);
        }
    }
}