From d6d130dbba2fcea78109ca647f552ba8fc57a39d Mon Sep 17 00:00:00 2001
From: qwertyforce <44163887+qwertyforce@users.noreply.github.com>
Date: Sat, 26 Dec 2020 12:56:08 +0300
Subject: [PATCH] Update search.tsx

---
 pages/search.tsx | 209 +++++++++++++++++++++++++++++------------------
 1 file changed, 129 insertions(+), 80 deletions(-)

diff --git a/pages/search.tsx b/pages/search.tsx
index 5e5e2d5..8cfe2f2 100644
--- a/pages/search.tsx
+++ b/pages/search.tsx
@@ -47,9 +47,7 @@ export default function Search(props: any) {
 
   )
 }
-
-
-function parse(query:string) {
+function parse(tokens: string[]) {
   const operators: any = []
   const operands: any = []
   const priority: any = {
@@ -58,8 +56,8 @@ function parse(query:string) {
     "||": 1
   }
   function operate(operator: string, a: any, b: any = 0) {
-    if(a===undefined || b===undefined){
-      return {error:true}
+    if (a === undefined || b === undefined) {
+      return { error: true }
     }
     let x = {}
     switch (operator) {
@@ -122,71 +120,9 @@ function parse(query:string) {
       }
     }
   }
-  function detect_brackets(str:string) {
-    const tokens = ["&&", "||", "!", ",","-"]
-    const tokens2 = ["&&", "||", "!", "(", ")", ",","-"]
-    const stack=[]
-    const closing_brackets=[]
-    const opening_brackets=[]
-    for(let i=0;i<str.length;i++){
-        if(tokens2.includes(str[i])){
-            stack.push({token:str[i],idx:i})
-        }
-        if(str[i+1] && tokens2.includes(str[i]+str[i+1])){
-            stack.push({token:str[i]+str[i+1],idx:i})
-        }
-        if(str[i]===")"){
-             let x:any=stack.pop()
-             let m=false
-             while(x.token!=="("){
-                 x=stack.pop()
-                 if(tokens.includes(x.token)){
-                     m=true
-                 }
-             }
-             if(!m && (x.idx>0 && (tokens.includes(str[x.idx-1])) || (str[x.idx-2] && tokens.includes(str[x.idx-2]+str[x.idx-1]))) || 
-             (x.idx===0)){
-                closing_brackets.push(i)
-                opening_brackets.push(x.idx)
-             }else if(m){
-                closing_brackets.push(i)
-                opening_brackets.push(x.idx)
-             }
-        }
-    }
-    const arr=str.split("")
-    for(let i=0;i<closing_brackets.length;i++){
-      arr[opening_brackets[i]]="(%"
-      arr[closing_brackets[i]]="%)"
-    }
-    str=arr.join("")
-    return str
-}
 
-
-  function split(str:any) {
-    const tokens = ["&&", "||", "!", "(%", "%)", ",","-"]
-    const temp_char = "#$#"
-    str=detect_brackets(str)
-    console.log(str)
-    for (const token of tokens) {
-      str = str.replaceAll(token, temp_char + token + temp_char)
-    }
-    const arr = str.split(temp_char).map((el:any)=>el.trim()).filter((el:any) => el !== "")
-    for(let i=0;i<arr.length;i++){
-      if(arr[i]==="(%"){
-        arr[i]="("
-      }
-      if(arr[i]==="%)"){
-        arr[i]=")"
-      }
-    }
-    return arr;
-  }
-
-  const query_splitted = split(query)
-  for (const word of query_splitted) {
-    switch (word) {
+  for (const token of tokens) {
+    switch (token) {
       case "||":
         x("||")
         break;
@@ -205,32 +141,145 @@ function parse(query:string) {
         execute_until_opening_bracket()
         break;
       default:
-        operands.push({ tags: word })
+        operands.push({ tags: token })
         break;
     }
   }
   execute_remaining()
-  if(operands.length!==1 || operators.length!==0){
-    return {error:true}
-  }else{
+  if (operands.length !== 1 || operators.length !== 0) {
+    return { error: true }
+  } else {
     return operands[0]
   }
 }
+function tokenize(query: string) {
+  function detect_brackets(str: string) {
+    const tokens = ["&&", "||", "#!", ",", "#-"];
+    const tokens2 = ["&&", "||", "#!", "(", ")", ",", "#-"];
+    const stack = [];
+    const closing_brackets = [];
+    const opening_brackets = [];
+    for (let i = 0; i < str.length; i++) {
+      if (tokens2.includes(str[i])) {
+        stack.push({ token: str[i], idx: i });
+      }
+      if (str[i + 1] && tokens2.includes(str[i] + str[i + 1])) {
+        stack.push({ token: str[i] + str[i + 1], idx: i });
+      }
+      if (stack.length > 0 && str[i] === ")") {
+        let x = stack.pop();
+        let m = false;
+        if (!x) {
+          return "##errror##"
+        }
+        while (x.token !== "(") {
+          x = stack.pop();
+          if (!x) {
+            return "##errror##"
+          }
+          if (tokens.includes(x.token)) {
+            m = true;
+          }
+        }
+        if (!m && (x.idx > 0 && (tokens.includes(str[x.idx - 1])) || (str[x.idx - 2] && tokens.includes(str[x.idx - 2] + str[x.idx - 1]))) ||
+          (x.idx === 0)) {
+          closing_brackets.push(i);
+          opening_brackets.push(x.idx);
+        }
+        else if (m) {
+          closing_brackets.push(i);
+          opening_brackets.push(x.idx);
+        }
+      }
+    }
+    const arr = str.split("");
+    for (let i = 0; i < closing_brackets.length; i++) {
+      arr[opening_brackets[i]] = "(%";
+      arr[closing_brackets[i]] = "%)";
+    }
+    str = arr.join("");
+    return str;
+  }
+  function not_operator_fix(str: string) {
+    const str_arr = str.split("");
+    const tokens = ["&&", "||", "!", ",", "-", "(", ")"];
+    const not_operators = ["!", "-"];
+    const stack = [];
+    for (let i = 0; i < str.length; i++) {
+      if (tokens.includes(str[i])) {
+        stack.push({ token: str[i], idx: i });
+      }
+      if (str[i + 1] && tokens.includes(str[i] + str[i + 1])) {
+        stack.push({ token: str[i] + str[i + 1], idx: i });
+      }
+    }
+    if (stack[0] && stack[0].idx === 0 && not_operators.includes(stack[0].token)) {
+      str_arr[0] = "#" + stack[0].token;
+    }
+    for (let i = 1; i < stack.length; i++) {
+      if (not_operators.includes(stack[i].token)) {
+        if (stack[i - 1].token !== ")" && stack[i - 1].token.length + stack[i - 1].idx === stack[i].idx) {
+          str_arr[stack[i].idx] = "#" + stack[i].token;
+        }
+      }
+    }
+    return str_arr.join("");
+  }
+  function split(str: string) {
+    const operators = ["&&", "||", "#!", "(%", "%)", ",", "#-"];
+    const temp_char = "#$#";
+    str = not_operator_fix(str);
+    str = detect_brackets(str);
+    if (str === "##errror##") {
+      return []
+    }
+    for (const operator of operators) {
+      str = str.replaceAll(operator, temp_char + operator + temp_char);
+    }
+    const arr = str.split(temp_char).map((el) => el.trim()).filter((el) => el !== "");
+    for (let i = 0; i < arr.length; i++) {
+      if (arr[i] === "(%") {
+        arr[i] = "(";
+      }
+      if (arr[i] === "#-") {
+        arr[i] = "-";
+      }
+      if (arr[i] === "#!") {
+        arr[i] = "!";
+      }
+      if (arr[i] === "%)") {
+        arr[i] = ")";
+      }
+    }
+    console.log(arr);
+    return arr;
+  }
+  return split(query)
+}
 
 
+function build_ast(str: string) {
+  const tokens = tokenize(str)
+  if (tokens.length === 0) {
+    return { error: true }
+  }
+  const ast = parse(tokens)
+  return ast
+}
+
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 export async function getServerSideProps(context: any) {
   if (context.query.q) {
-    if(context.query.q.includes("$")){
+    if (context.query.q.includes("$")) {  //anti - nosql injection or something
       return {
-        props: { err: true } 
+        props: { err: true }
       }
     }
     console.log(context.query.q)
-    const query=parse(context.query.q)
-    if(query.error){
+    const query = build_ast(context.query.q)
+    if (query.error) {
       return {
-        props: { err: true } 
+        props: { err: true }
       }
     }
     const images = await db_ops.image_ops.find_images_by_tags(query)
@@ -242,7 +291,7 @@ export async function getServerSideProps(context: any) {
     } else {
       page = 1
     }
-    page = Math.max(page,1)
+    page = Math.max(page, 1)
     if (page <= Math.ceil(images.length / images_on_page)) {
       for (let i = (page - 1) * images_on_page; (i < (page) * images_on_page) && (i < images.length); i++) {
         photos.push({
@@ -263,6 +312,6 @@ export async function getServerSideProps(context: any) {
     }
   }
   return {
-    props: { err: true } 
+    props: { err: true }
   }
 }
\ No newline at end of file