重构AST抽象rewrite

1 files changed, 137 insertions, 0 deletions

diff --git a/src/ast/parser/emphasis.rs b/src/ast/parser/emphasis.rs
new file mode 100644
index 0000000..c8e6b9b
--- /dev/null
+++ b/src/ast/parser/emphasis.rs
@@ -0,0 +1,137 @@
+use crate::ast::parser::{ParserInternalStatus, ParserMatchResult};
+
+#[derive(Default)]
+struct EmphasisTmp {
+    /// 强调开始的列
+    emphasis_begin_col: u16,
+
+    /// 前缀，用于后缀匹配
+    prefix_count: String,
+
+    /// 是否正在输入强调前缀
+    typing_emphasis_prefix: bool,
+
+    /// 是否正在输入强调内容
+    typing_emphasis_content: bool,
+}
+
+#[derive(Default, PartialEq, Eq)]
+#[repr(u8)]
+enum Style {
+    /// 无样式
+    #[default]
+    None,
+
+    /// 星号
+    Star,
+
+    /// 下划线
+    Underline,
+}
+
+impl Style {
+    /// 反转样式
+    pub fn invert(&self) -> Style {
+        match self {
+            Style::Underline => Style::Star,
+            Style::Star => Style::Underline,
+            Style::None => Style::None,
+        }
+    }
+}
+
+impl std::fmt::Display for Style {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Style::None => write!(f, ""),
+            Style::Star => write!(f, "*"),
+            Style::Underline => write!(f, "_"),
+        }
+    }
+}
+
+impl From<Style> for char {
+    fn from(style: Style) -> char {
+        match style {
+            Style::None => ' ',
+            Style::Star => '*',
+            Style::Underline => '_',
+        }
+    }
+}
+
+fn get_tmp<'a>(inr: &'a mut ParserInternalStatus) -> &'a mut EmphasisTmp {
+    inr.get_tmp_or_init::<EmphasisTmp>("emphasis_tmp")
+}
+
+pub(crate) fn proc(c: &char, inr: &mut ParserInternalStatus) -> ParserMatchResult {
+    match c {
+        // 输入能被识别的符号时
+
+        // 星星
+        '*' => typed_emphasis_char(Style::Star, inr),
+
+        // 下划线
+        '_' => typed_emphasis_char(Style::Underline, inr),
+
+        // 输入其他字符时
+        _ => typed_other_char(c, inr),
+    }
+}
+
+fn typed_emphasis_char(s: Style, inr: &mut ParserInternalStatus) -> ParserMatchResult {
+    let col = inr.col;
+    let tmp = get_tmp(inr);
+
+    // 如果没设置样式（没初始化）
+    if tmp.prefix_style == Style::None {
+        // 设置样式
+        tmp.prefix_style = s;
+        // 设置前缀长度
+        tmp.prefix_count = 1;
+        // 设置开始位置
+        tmp.emphasis_begin_col = col;
+
+        tmp.typing_emphasis_prefix = true;
+        tmp.typing_emphasis_content = false;
+    } else
+    // 如果设置了样式，则判断其是否匹配
+    if tmp.prefix_style == s {
+        // 如果匹配，增加前缀长度
+        tmp.prefix_count += 1;
+
+        // 增加长度后，如果前缀长度大于 3（最长），将报语法错误
+        if tmp.prefix_count > 3 {
+            return ParserMatchResult::SyntaxError {
+                begin_col: tmp.emphasis_begin_col,
+                begin_row: inr.row,
+                end_col: inr.col,
+                end_row: inr.row,
+                msg: "Emphasis characters can be at most 3".to_string(),
+            };
+        }
+    } else {
+        // 如果不匹配，将报语法错误
+        return ParserMatchResult::SyntaxError {
+            begin_col: inr.col,
+            begin_row: inr.row,
+            end_col: inr.col,
+            end_row: inr.row,
+            msg: format!(
+                "Emphasis statement (style: \"{}\") cannot use another emphasis statement (style: \"{}\") before closing",
+                s.invert(),
+                s
+            ),
+        };
+    }
+
+    ParserMatchResult::Done
+}
+
+fn typed_other_char(c: &char, inr: &mut ParserInternalStatus) -> ParserMatchResult {
+    let tmp = get_tmp(inr);
+
+    // 修改当前状态
+    tmp.typing_emphasis_prefix = false;
+    tmp.typing_emphasis_content = true;
+}