**1. Functional Requirements**

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**1.1 User Requirements**

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**1.1.1 Browsing Programming Languages**

- **1.1.1.1** Users **shall be** able to browse a catalog of programming languages sourced from Wikidata.
- **1.1.1.2** Users **shall be** able to view detailed information about the language's origin.
- **1.1.1.3** Users **should be** able to filter programming languages based on attributes such syntactic similarity or domain of use.
- **1.1.1.4** Users **shall be** able to search for programming languages by name or attributes.
- **1.1.1.5** Users **should be** able to see related programming languages, such as predecessors, successors, or those with similar features.
- **1.1.1.6** Users **should be** able to compare multiple programming languages side by side and see the streghts and weaknesses.
- **1.1.1.7** Users **should be** able to bookmark or save programming languages for future reference.
- **1.1.1.8** Users **should be** able to report incorrect or outdated information.
- **1.1.1.9** Users **should be** able to access code examples or snippets associated with programming languages.

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**1.1.2 Question Search**

- **1.1.2.1** Users **shall be** able to search for questions within the forum using keywords. Those keyword may be assigned by admins.
- **1.1.2.2** Users **should be** able to filter search results by date range, programming language, tags, or user.
- **1.1.2.3** Users **should be** able to sort search results by relevance(?), date posted, or number of responses.
- **1.1.2.4** Users **should be** able to receive suggestions for similar questions when viewing a question. (?)
- **1.1.2.5** Users **should be** able to save or bookmark search queries for future use. (?)
- **1.1.2.6** Users **shall be** able to search within specific forums or categories.
- **1.1.2.7** Users **should be** able to search for code snippets within questions and answers.
- **1.1.2.8** Users **should be** able to receive notifications for new questions matching their saved search criteria. (?)
- **1.1.2.9** Users **shall be** prevented from posting duplicate questions by being prompted with similar existing questions.
- **1.1.2.10** Users **should be** able to use advanced search operators (e.g., AND, OR, NOT) in their queries.
- **1.1.2.11** Users **should be** able to see highlighted search terms in the search results.

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**1.2 System Requirements**

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**1.2.1 Browsing Programming Languages Functionality**

- **1.2.1.1** The system **shall** retrieve programming language data from Wikidata.
- **1.2.1.2** The system **shall** provide a user interface that displays programming languages in an organized manner, such as lists or grids (or both).
- **1.2.1.3** The system **shall** allow users to view detailed information and basic examples about each programming language.
- **1.2.1.4** The system **shall** implement filtering functionality, enabling users to filter programming languages based on fundamental attributes.
- **1.2.1.5** The system **shall** implement a search function to search programming languages by name or attributes.
- **1.2.1.6** The system **should** display related programming languages based on predefined relationships in the data.
- **1.2.1.7** The system **should** allow users to compare multiple programming languages side by side.
- **1.2.1.8** The system **should** allow users to bookmark or save programming languages for future reference.
- **1.2.1.9** The system **should** provide an option for users to report incorrect or outdated information, which will be reviewed by administrators. (?)
- **1.2.1.10** The system **should** support localization, displaying data in different languages if available in Wikidata. (?)
- **1.2.1.11** The system **shall** ensure that the user interface for browsing is accessible and user-friendly.
- **1.2.1.12** The system **should** provide access to code examples or snippets associated with programming languages.
- **1.2.1.13** The system **should** allow users to customize the display settings for browsing programming languages. (?)
- **1.2.1.14** The system **shall** ensure data consistency and integrity when fetching and displaying information from Wikidata.

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**1.2.2 Question Search Functionality**

- **1.2.2.1** The system **shall** provide a search functionality for users to search questions in the forum using keywords.
- **1.2.2.2** The system **shall** include filtering options in the search functionality, such as date range, programming language, tags, or user.
- **1.2.2.3** The system **shall** display search results matching the search criteria, including question title, brief excerpt, date, and number of answers.
- **1.2.2.4** The system **shall** allow users to sort search results by relevance, date posted, or number of responses.
- **1.2.2.5** The system **should** provide suggestions for similar questions when users are viewing a question.
- **1.2.2.6** The system **should** allow users to save or bookmark search queries for future use. (?)
- **1.2.2.7** The system **shall** enable users to search within specific forums or categories.
- **1.2.2.8** The system **shall** make the search functionality accessible from any page within the forum.
- **1.2.2.9** The system **should** highlight search terms in the search results.
- **1.2.2.10** The system **should** handle misspelled search queries by suggesting corrections.
- **1.2.2.11** The system **should** support advanced search operators (e.g., AND, OR, NOT).
- **1.2.2.12** The system **shall** prevent duplicate questions by prompting users with similar existing questions when they attempt to post a new question.
- **1.2.2.13** The system **shall** ensure that search performance is optimized to return results promptly.
- **1.2.2.14** The system **should** allow users to search for code snippets within questions and answers.
- **1.2.2.15** The system **should** provide a "Did you mean..." feature for ambiguous or unclear search terms.
- **1.2.2.16** The system **should** respect user permissions and privacy settings, displaying only content the user has access to.
- **1.2.2.17** The system **should** allow users to receive notifications for new questions matching their saved search criteria. (?)
- **1.2.2.18** The system **shall** index all forum content regularly to maintain up-to-date search results.
- **1.2.2.19** The system **should** integrate with the code execution platform to allow searching for runnable code examples.

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*Requirements marked with (?) are open to change.*

# Diagrams for Browsing Programming Languages and Question Search

### **2.1 Browsing Programming Languages Use Case**

flowchart

    User --> BrowseLanguages;
    BrowseLanguages -. "include" .-> FilterLanguages;
    BrowseLanguages -. "include" .-> SearchLanguages;
    BrowseLanguages -. "include" .-> ViewRelatedLanguages;
    BrowseLanguages -. "include" .-> CompareLanguages;
    BrowseLanguages -. "include" .-> BookmarkLanguages;
    BrowseLanguages --> ViewLanguageDetails;
    
    ViewLanguageDetails -. "extend" .-> ReportIncorrectInfo;
    ViewLanguageDetails -. "extend" .-> ViewCodeSnippets;
    ViewLanguageDetails -. "extend" .-> CustomizeView;

**Explanation:**

- **User** initiates the **BrowseLanguages** use case.
- **BrowseLanguages** includes functionalities like:
- **FilterLanguages**
- **SearchLanguages**
- **ViewRelatedLanguages**
- **CompareLanguages**
- **BookmarkLanguages**
- **BrowseLanguages** leads to **ViewLanguageDetails**.
- **ViewLanguageDetails** can be extended with:
- **ReportIncorrectInfo**
- **ViewCodeSnippets**
- **CustomizeView**

---

### **2.2 Question Search Use Case**

flowchart

    User --> SearchQuestions;
    SearchQuestions -. "include" .-> FilterSearchResults;
    SearchQuestions -. "include" .-> SortSearchResults;
    SearchQuestions -. "include" .-> SearchWithinForums;
    SearchQuestions -. "include" .-> UseAdvancedSearch;
    SearchQuestions -. "include" .-> SearchCodeSnippets;
    SearchQuestions --> ViewQuestionDetails;
    
    ViewQuestionDetails -. "extend" .-> SaveSearchQueries;
    ViewQuestionDetails -. "extend" .-> ReceiveNotifications;
    ViewQuestionDetails -. "extend" .-> ViewSimilarQuestions;
    ViewQuestionDetails -. "extend" .-> PreventDuplicateQuestions;

**Explanation:**

- **User** initiates the **SearchQuestions** use case.
- **SearchQuestions** includes functionalities like:
- **FilterSearchResults**
- **SortSearchResults**
- **SearchWithinForums**
- **UseAdvancedSearch**
- **SearchCodeSnippets**
- **SearchQuestions** leads to **ViewQuestionDetails**.
- **ViewQuestionDetails** can be extended with:
- **SaveSearchQueries**
- **ReceiveNotifications**
- **ViewSimilarQuestions**
- **PreventDuplicateQuestions**

---

### **3. Class Diagram**

classDiagram
    class User {
        +userID: int
        +username: string
        +email: string
        +bookmarkLanguage(languageID: int)
        +searchQuestions(query: string)
        +reportIncorrectInfo(languageID: int, report: string)
    }

    class ProgrammingLanguage {
        +languageID: int
        +name: string
        +creator: string
        +yearCreated: int
        +paradigm: string[]
        +typingDiscipline: string
        +influencedBy: string[]
        +influenced: string[]
        +getDetails(): LanguageDetails
    }

    class LanguageDetails {
        +languageID: int
        +description: string
        +codeExamples: string[]
        +relatedLanguages: string[]
        +displayDetails()
    }

    class Bookmark {
        +userID: int
        +languageID: int
        +dateBookmarked: Date
    }

    class SearchQuery {
        +queryText: string
        +filters: FilterOptions
        +executeSearch(): SearchResult[]
    }

    class FilterOptions {
        +dateRange: DateRange
        +languages: string[]
        +tags: string[]
        +applyFilters()
    }

    class SearchResult {
        +questionID: int
        +title: string
        +excerpt: string
        +datePosted: Date
        +numberOfAnswers: int
    }

    class Question {
        +questionID: int
        +title: string
        +body: string
        +datePosted: Date
        +tags: string[]
        +codeSnippets: string[]
    }

    User --> ProgrammingLanguage : views
    User --> Bookmark : creates
    User --> SearchQuery : initiates
    SearchQuery --> SearchResult : returns
    SearchResult --> Question : links to
    ProgrammingLanguage --> LanguageDetails : provides
    ProgrammingLanguage --> ProgrammingLanguage : related to
    User --> Question : posts, views

**Explanation:**

- **User** interacts with **ProgrammingLanguage**, can **bookmark** languages, and **search** for questions.
- **ProgrammingLanguage** provides **LanguageDetails**, which include descriptions and code examples.
- **SearchQuery** uses **FilterOptions** to refine the search and returns **SearchResult**.
- **SearchResult** links to **Question**, which contains the full details.
- **ProgrammingLanguage** may be related to other programming languages.

---

### **4. Sequence Diagram**

#### **4.1 Browsing Programming Languages Sequence Diagram**

sequenceDiagram
    participant User
    participant Browser
    participant PageController
    participant WikidataAPI
    participant LanguageController
    participant Database

    User->>Browser: Navigate to Browse Languages
    Browser->>PageController: Request BrowseLanguages Page
    PageController->>WikidataAPI: Fetch Language List
    WikidataAPI->>PageController: Return Language Data
    PageController->>LanguageController: Process Language Data
    LanguageController->>Database: Store/Update Languages
    LanguageController->>Browser: Display Language List
    User->>Browser: Apply Filters/Search
    Browser->>LanguageController: Request Filtered/Search Results
    LanguageController->>Database: Query with Filters/Search Terms
    Database->>LanguageController: Return Filtered Language Data
    LanguageController->>Browser: Display Filtered Language List
    User->>Browser: Select Language for Details
    Browser->>LanguageController: Request Language Details
    LanguageController->>Database: Retrieve Language Details
    LanguageController->>Browser: Display Language Details
    User->>Browser: ViewCodeSnippets/ReportIncorrectInfo/CustomizeView

#### **4.2 Question Search Sequence Diagram**

sequenceDiagram
    participant User
    participant Browser
    participant SearchController
    participant ForumDatabase
    participant WikidataAPI
    participant ResultPage

    User->>Browser: Enter Search Query
    Browser->>SearchController: Submit Query
    SearchController->>ForumDatabase: Search Questions
    ForumDatabase->>SearchController: Return Question Results
    SearchController->>WikidataAPI: Search Wikidata (if applicable)
    WikidataAPI->>SearchController: Return Wikidata Results
    SearchController->>ResultPage: Compile and Send Results
    ResultPage->>Browser: Display Results
    User->>Browser: Apply Filters/Sort Options
    Browser->>ResultPage: Request Updated Results
    ResultPage->>SearchController: Process Filters/Sort
    SearchController->>ForumDatabase: Query with Filters/Sort
    ForumDatabase->>SearchController: Return Updated Results
    SearchController->>ResultPage: Send Updated Results
    ResultPage->>Browser: Display Updated Results
    User->>Browser: ViewQuestionDetails
    Browser->>ForumDatabase: Retrieve Question Details
    ForumDatabase->>Browser: Send Question Details
    Browser->>User: Display Question Details
    User->>Browser: SaveSearchQueries/ReceiveNotifications

**Explanation:**

- **Browsing Programming Languages:**
- The **User** navigates to browse languages.
- The **PageController** fetches data from **WikidataAPI**.
- Data is processed by **LanguageController** and stored in the **Database**.
- The **User** can apply filters or search terms, and the system updates the displayed languages accordingly.
- When a language is selected, detailed information is retrieved and displayed.
- **Question Search:**
- The **User** enters a search query.
- The **SearchController** searches the **ForumDatabase** and may also query **WikidataAPI**.
- Results are compiled and displayed on the **ResultPage**.
- The **User** can apply filters or sorting options to refine results.
- Upon selecting a question, details are retrieved from the **ForumDatabase** and displayed.

---

sequenceDiagram
    participant User
    participant Browser
    participant LanguageController
    participant WikidataAPI

    User->>Browser: Search(keyword)
    Browser->>Wikidata: getLanguage(keyword)
    Wikidata->>Browser: top5MatchedWords
    

    
    Browser->>Wikidata: getLanguageDetails(language)
    
    
    Browser->>LanguageController: filterLanguages(filters)

    LanguageController->>WikidataAPI: queryLanguages(filters)
    WikidataAPI-->>LanguageController: filteredLanguages
    LanguageController-->>Browser: displayLanguages(filteredLanguages)

    User->>Browser: Select Language for Details
    Browser->>LanguageController: getLanguageDetails(languageId)
    LanguageController->>WikidataAPI: fetchLanguageDetails(languageId)
    WikidataAPI-->>LanguageController: languageDetails
    LanguageController-->>Browser: displayLanguageDetails(languageDetails)

flowchart
    User --> SearchLanguages
    User --> FilterLanguages
    User --> ViewQuestionsAboutLanguage

    SearchLanguages --> Browser
    Browser --> GetWordsFromAPI
    Browser --> GetLanguageDetails

    GetWordsFromAPI --> WikidataAPI
    GetLanguageDetails --> WikidataAPI

    ViewQuestionsAboutLanguage --> LanguageController
    LanguageController --> ShowLanguageDetails
    LanguageController --> ShowRelatedPosts

    ShowLanguageDetails --> WikidataAPI
    ShowRelatedPosts --> WikidataAPI

    FilterLanguages --> LanguageController
    FilterLanguages -.-> |extend| ViewQuestionsAboutLanguage

    LanguageController --> FilteredPosts