From 2e575857872679ce8ebb1eda9e7b1b30f5dd3139 Mon Sep 17 00:00:00 2001
From: Oliver Hamlet <oliver.hamlet@gmail.com>
Date: Wed, 3 Oct 2018 18:31:26 +0100
Subject: [PATCH] Add evaluation of active() and many_active() conditions

---
 src/function/eval.rs | 101 +++++++++++++++++++++++++++++++++++++++++++
 src/lib.rs           |   3 ++
 2 files changed, 104 insertions(+)

diff --git a/src/function/eval.rs b/src/function/eval.rs
index 3917a5e..8cecf59 100644
--- a/src/function/eval.rs
+++ b/src/function/eval.rs
@@ -92,6 +92,32 @@ fn evaluate_many(state: &State, parent_path: &Path, regex: &Regex) -> Result<boo
     Ok(false)
 }
 
+fn evaluate_active_path(state: &State, path: &Path) -> Result<bool, Error> {
+    Ok(path
+        .to_str()
+        .map(|s| state.active_plugins.contains(&s.to_lowercase()))
+        .unwrap_or(false))
+}
+
+fn evaluate_active_regex(state: &State, regex: &Regex) -> Result<bool, Error> {
+    Ok(state.active_plugins.iter().any(|p| regex.is_match(p)))
+}
+
+fn evaluate_many_active(state: &State, regex: &Regex) -> Result<bool, Error> {
+    let mut found_one = false;
+    for active_plugin in &state.active_plugins {
+        if regex.is_match(&active_plugin) {
+            if found_one {
+                return Ok(true);
+            } else {
+                found_one = true;
+            }
+        }
+    }
+
+    Ok(false)
+}
+
 impl Function {
     pub fn eval(&self, state: &State) -> Result<bool, Error> {
         // TODO: Handle all variants.
@@ -99,7 +125,10 @@ impl Function {
         match *self {
             Function::FilePath(ref f) => evaluate_file_path(state, f),
             Function::FileRegex(ref p, ref r) => evaluate_file_regex(state, p, r),
+            Function::ActivePath(ref p) => evaluate_active_path(state, p),
+            Function::ActiveRegex(ref r) => evaluate_active_regex(state, r),
             Function::Many(ref p, ref r) => evaluate_many(state, p, r),
+            Function::ManyActive(ref r) => evaluate_many_active(state, r),
             _ => Ok(false),
         }
     }
@@ -117,6 +146,10 @@ mod tests {
     use GameType;
 
     fn state<T: Into<PathBuf>>(data_path: T) -> State {
+        state_with_active_plugins(data_path, &[])
+    }
+
+    fn state_with_active_plugins<T: Into<PathBuf>>(data_path: T, active_plugins: &[&str]) -> State {
         let data_path = data_path.into();
         if !data_path.exists() {
             create_dir(&data_path).unwrap();
@@ -125,6 +158,10 @@ mod tests {
         State {
             game_type: GameType::tes4,
             data_path: data_path,
+            active_plugins: active_plugins
+                .into_iter()
+                .map(|s| s.to_lowercase())
+                .collect(),
         }
     }
 
@@ -219,6 +256,46 @@ mod tests {
         assert!(function.eval(&state).unwrap());
     }
 
+    #[test]
+    fn function_active_path_eval_should_be_true_if_the_path_is_an_active_plugin() {
+        let function = Function::ActivePath(PathBuf::from("Blank.esp"));
+        let state = state_with_active_plugins(".", &["Blank.esp"]);
+
+        assert!(function.eval(&state).unwrap());
+    }
+
+    #[test]
+    fn function_active_path_eval_should_be_case_insensitive() {
+        let function = Function::ActivePath(PathBuf::from("Blank.esp"));
+        let state = state_with_active_plugins(".", &["blank.esp"]);
+
+        assert!(function.eval(&state).unwrap());
+    }
+
+    #[test]
+    fn function_active_path_eval_should_be_false_if_the_path_is_not_an_active_plugin() {
+        let function = Function::ActivePath(PathBuf::from("inactive.esp"));
+        let state = state_with_active_plugins(".", &["Blank.esp"]);
+
+        assert!(!function.eval(&state).unwrap());
+    }
+
+    #[test]
+    fn function_active_regex_eval_should_be_true_if_the_regex_matches_an_active_plugin() {
+        let function = Function::ActiveRegex(regex("Blank\\.esp"));
+        let state = state_with_active_plugins(".", &["Blank.esp"]);
+
+        assert!(function.eval(&state).unwrap());
+    }
+
+    #[test]
+    fn function_active_regex_eval_should_be_false_if_the_regex_does_not_match_an_active_plugin() {
+        let function = Function::ActiveRegex(regex("inactive\\.esp"));
+        let state = state_with_active_plugins(".", &["Blank.esp"]);
+
+        assert!(!function.eval(&state).unwrap());
+    }
+
     #[test]
     fn function_many_eval_should_be_false_if_no_directory_entries_match() {
         let function = Function::Many(PathBuf::from("."), regex("missing"));
@@ -256,4 +333,28 @@ mod tests {
 
         assert!(function.eval(&state).unwrap());
     }
+
+    #[test]
+    fn function_many_active_eval_should_be_true_if_the_regex_matches_more_than_one_active_plugin() {
+        let function = Function::ManyActive(regex("Blank.*"));
+        let state = state_with_active_plugins(".", &["Blank.esp", "Blank.esm"]);
+
+        assert!(function.eval(&state).unwrap());
+    }
+
+    #[test]
+    fn function_many_active_eval_should_be_false_if_one_active_plugin_matches() {
+        let function = Function::ManyActive(regex("Blank\\.esp"));
+        let state = state_with_active_plugins(".", &["Blank.esp", "Blank.esm"]);
+
+        assert!(!function.eval(&state).unwrap());
+    }
+
+    #[test]
+    fn function_many_active_eval_should_be_false_if_the_regex_does_not_match_an_active_plugin() {
+        let function = Function::ManyActive(regex("inactive\\.esp"));
+        let state = state_with_active_plugins(".", &["Blank.esp", "Blank.esm"]);
+
+        assert!(!function.eval(&state).unwrap());
+    }
 }
diff --git a/src/lib.rs b/src/lib.rs
index 77c5548..8615f62 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -5,6 +5,7 @@ extern crate regex;
 #[cfg(test)]
 extern crate tempfile;
 
+use std::collections::HashSet;
 use std::io;
 use std::path::PathBuf;
 use std::str;
@@ -61,6 +62,7 @@ impl GameType {
 pub struct State {
     game_type: GameType,
     data_path: PathBuf,
+    active_plugins: HashSet<String>, // Lowercased plugin filenames.
 }
 
 // Compound conditions joined by 'or'
@@ -160,6 +162,7 @@ mod tests {
         State {
             game_type: GameType::tes4,
             data_path: data_path,
+            active_plugins: HashSet::new(),
         }
     }