Move builtin framework impl to its own module

The framework is now moved in its entirity to the `framework` module,
with the `Framework` trait currently on its own and the builtin
implementation provided.

The builtin implementation has been renamed to "Standard".

Upgrade path:

Rename the `BuiltinFramework` import to `StandardFramework`. Instead of
importing builtin framework items from `serenity::framework`, import
them from `serenity::framework::standard`.

This is the beginning to #60. The root `framework` module (non-standard
implementation) will be built more by the time it's closed.

1 files changed, 157 insertions, 0 deletions

diff --git a/src/framework/standard/command.rs b/src/framework/standard/command.rs
new file mode 100644
index 0000000..01c4c5e
--- /dev/null
+++ b/src/framework/standard/command.rs
@@ -0,0 +1,157 @@
+use std::sync::Arc;
+use super::Configuration;
+use client::Context;
+use model::{Message, Permissions};
+use std::collections::HashMap;
+
+pub type Check = Fn(&mut Context, &Message, &[String], &Arc<Command>) -> bool + 'static;
+pub type Exec = Fn(&mut Context, &Message, Vec<String>, String) -> Result<(), String> + 'static;
+pub type Help = Fn(&mut Context,
+                   &Message,
+                   HashMap<String, Arc<CommandGroup>>,
+                   &[String])
+                   -> Result<(), String>
+                    + 'static;
+pub type BeforeHook = Fn(&mut Context, &Message, &str) -> bool + 'static;
+pub type AfterHook = Fn(&mut Context, &Message, &str, Result<(), String>) + 'static;
+pub(crate) type InternalCommand = Arc<Command>;
+pub type PrefixCheck = Fn(&mut Context, &Message) -> Option<String> + 'static;
+
+pub enum CommandOrAlias {
+    Alias(String),
+    Command(InternalCommand),
+}
+
+/// Command function type. Allows to access internal framework things inside
+/// your commands.
+pub enum CommandType {
+    StringResponse(String),
+    Basic(Box<Exec>),
+    WithCommands(Box<Help>),
+}
+
+#[derive(Default)]
+pub struct CommandGroup {
+    pub prefix: Option<String>,
+    pub commands: HashMap<String, CommandOrAlias>,
+}
+
+/// Command struct used to store commands internally.
+pub struct Command {
+    /// A set of checks to be called prior to executing the command. The checks
+    /// will short-circuit on the first check that returns `false`.
+    pub checks: Vec<Box<Check>>,
+    /// Function called when the command is called.
+    pub exec: CommandType,
+    /// Ratelimit bucket.
+    pub bucket: Option<String>,
+    /// Command description, used by other commands.
+    pub desc: Option<String>,
+    /// Example arguments, used by other commands.
+    pub example: Option<String>,
+    /// Command usage schema, used by other commands.
+    pub usage: Option<String>,
+    /// Whether arguments should be parsed using quote parser or not.
+    pub use_quotes: bool,
+    /// Minumum amount of arguments that should be passed.
+    pub min_args: Option<i32>,
+    /// Maximum amount of arguments that can be passed.
+    pub max_args: Option<i32>,
+    /// Permissions required to use this command.
+    pub required_permissions: Permissions,
+    /// Whether command should be displayed in help list or not, used by other commands.
+    pub help_available: bool,
+    /// Whether command can be used only privately or not.
+    pub dm_only: bool,
+    /// Whether command can be used only in guilds or not.
+    pub guild_only: bool,
+    /// Whether command can only be used by owners or not.
+    pub owners_only: bool,
+    pub(crate) aliases: Vec<String>,
+}
+
+impl Command {
+    pub fn new<F>(f: F) -> Self
+        where F: Fn(&mut Context, &Message, Vec<String>, String) -> Result<(), String> + 'static {
+        Command {
+            aliases: Vec::new(),
+            checks: Vec::default(),
+            exec: CommandType::Basic(Box::new(f)),
+            desc: None,
+            usage: None,
+            example: None,
+            use_quotes: false,
+            dm_only: false,
+            bucket: None,
+            guild_only: false,
+            help_available: true,
+            min_args: None,
+            max_args: None,
+            owners_only: false,
+            required_permissions: Permissions::empty(),
+        }
+    }
+}
+
+pub fn positions(ctx: &mut Context, msg: &Message, conf: &Configuration) -> Option<Vec<usize>> {
+    if !conf.prefixes.is_empty() || conf.dynamic_prefix.is_some() {
+        // Find out if they were mentioned. If not, determine if the prefix
+        // was used. If not, return None.
+        let mut positions: Vec<usize> = vec![];
+
+        if let Some(mention_end) = find_mention_end(&msg.content, conf) {
+            positions.push(mention_end);
+        } else if let Some(ref func) = conf.dynamic_prefix {
+            if let Some(x) = func(ctx, msg) {
+                if msg.content.starts_with(&x) {
+                    positions.push(x.len());
+                }
+            } else {
+                for n in &conf.prefixes {
+                    if msg.content.starts_with(n) {
+                        positions.push(n.len());
+                    }
+                }
+            }
+        } else {
+            for n in &conf.prefixes {
+                if msg.content.starts_with(n) {
+                    positions.push(n.len());
+                }
+            }
+        };
+
+        if positions.is_empty() {
+            return None;
+        }
+
+        if conf.allow_whitespace {
+            let pos = *unsafe { positions.get_unchecked(0) };
+
+            positions.insert(0, pos + 1);
+        }
+
+        Some(positions)
+    } else if conf.on_mention.is_some() {
+        find_mention_end(&msg.content, conf).map(|mention_end| {
+            let mut positions = vec![mention_end];
+
+            if conf.allow_whitespace {
+                positions.insert(0, mention_end + 1);
+            }
+
+            positions
+        })
+    } else {
+        None
+    }
+}
+
+fn find_mention_end(content: &str, conf: &Configuration) -> Option<usize> {
+    conf.on_mention.as_ref().and_then(|mentions| {
+        mentions
+            .iter()
+            .find(|mention| content.starts_with(&mention[..]))
+            .map(|m| m.len())
+    })
+}