RustedSciThe 0.4.0

/// Structural context for tracking expression hierarchy and preventing layout conflicts.
///
/// Each layout element belongs to a structural family to enable conflict detection
/// and resolution during the rendering process. This prevents mathematical elements
/// from overlapping when complex expressions are combined.
#[derive(Debug, Clone)]
pub struct StructuralContext {
    /// Optional parent structure ID for hierarchical tracking.
    /// Used to determine structural families and resolve layout conflicts.
    parent_id: Option<usize>,
}

/// A single text element in the mathematical expression layout.
///
/// Represents one piece of text (variable, operator, function name, etc.) with its
/// positioning information. Multiple elements at different levels combine to form
/// the complete mathematical expression.
#[derive(Debug, Clone)]
pub struct LayoutElement {
    /// The actual text content to be rendered (e.g., "x", "+", "sin", "─")
    content: String,

    /// Vertical level where this element should be placed.
    /// - Positive levels: above baseline (exponents, numerators)
    /// - Zero level: baseline (main expression)
    /// - Negative levels: below baseline (denominators, subscripts)
    level: i32,

    /// Horizontal position (column) where this element starts.
    /// Used for proper alignment when combining multiple elements on the same level.
    position: usize,

    /// Unique identifier linking this element to its structural context.
    /// Enables conflict detection and resolution during rendering.
    structure_id: usize,
}

/// Multi-level layout system for mathematical expression rendering.
///
/// Manages the positioning and rendering of mathematical expressions across multiple
/// vertical levels. Handles complex structures like fractions (numerator/denominator),
/// exponents, and nested functions while maintaining proper mathematical formatting.
///
/// ## Layout Strategy
///
/// - **Level-based positioning**: Each part of the expression is assigned a vertical level
/// - **Structure isolation**: Different mathematical constructs maintain separate structural contexts
/// - **Conservative gap management**: Minimal spacing between levels while preventing overlap
/// - **Conflict resolution**: Structural awareness prevents elements from interfering with each other
#[derive(Debug, Clone)]
pub struct LeveledLayout {
    /// Collection of all text elements that make up the expression.
    /// Elements are positioned across multiple levels and will be rendered
    /// into a multi-line string representation.
    elements: Vec<LayoutElement>,

    /// The reference level (typically 0) representing the main expression line.
    /// Positive levels are above baseline, negative levels are below.
    pub baseline: i32,

    /// Total horizontal width needed to accommodate all elements.
    /// Used for proper alignment and spacing calculations.
    total_width: usize,

    /// Maps each level to its height requirement (typically 1 for text lines).
    /// Used during rendering to determine which levels actually contain content.
    pub level_heights: std::collections::HashMap<i32, usize>,

    /// Maps structure IDs to their contexts for hierarchical tracking.
    /// Enables conflict detection and resolution between different mathematical structures.
    contexts: std::collections::HashMap<usize, StructuralContext>,

    /// Counter for generating unique structure IDs.
    /// Ensures each mathematical construct gets a unique identifier.
    next_structure_id: usize,
}

impl LeveledLayout {
    /// Creates a new empty layout system.
    ///
    /// Initializes all collections and sets baseline to 0 (main expression level).
    /// The layout is ready to accept elements and perform mathematical formatting.
    pub fn new() -> Self {
        Self {
            elements: Vec::new(),
            baseline: 0,
            total_width: 0,
            level_heights: std::collections::HashMap::new(),
            contexts: std::collections::HashMap::new(),
            next_structure_id: 0,
        }
    }

    /// Creates a new structural context for tracking expression hierarchy.
    ///
    /// Each mathematical construct (variable, operator, function, etc.) gets its own
    /// structural context to enable conflict detection and proper rendering isolation.
    ///
    /// # Arguments
    /// * `_path` - Structural path (currently unused but reserved for future enhancements)
    /// * `parent_id` - Optional parent structure for hierarchical relationships
    /// * `_depth` - Nesting depth (currently unused but reserved for future enhancements)
    ///
    /// # Returns
    /// Unique structure ID for the created context
    pub fn create_structure_context(
        &mut self,
        _path: Vec<String>,
        parent_id: Option<usize>,
        _depth: usize,
    ) -> usize {
        let structure_id = self.next_structure_id;
        self.next_structure_id += 1;

        let context = StructuralContext { parent_id };

        self.contexts.insert(structure_id, context.clone());
        structure_id
    }

    /// Adds a text element to the layout with specified structural context.
    ///
    /// Places the element at the current total width position and updates layout metrics.
    /// The element will be rendered at the specified level with proper structural tracking.
    ///
    /// # Arguments
    /// * `content` - Text content to be rendered
    /// * `level` - Vertical level for positioning (0=baseline, +above, -below)
    /// * `structure_id` - ID linking this element to its structural context
    pub fn add_element_with_context(&mut self, content: String, level: i32, structure_id: usize) {
        let position = self.total_width;

        self.elements.push(LayoutElement {
            content: content.clone(),
            level,
            position,
            structure_id,
        });
        self.total_width += content.chars().count();
        *self.level_heights.entry(level).or_insert(0) =
            (*self.level_heights.get(&level).unwrap_or(&0)).max(1);
    }

    /// Wraps the entire current layout in parentheses.
    ///
    /// Shifts all existing elements to the right and adds opening/closing brackets
    /// at the baseline level. Used when operator precedence requires bracketing
    /// for mathematical correctness.
    ///
    /// # Layout Changes
    /// - All existing elements are shifted right by 1 position
    /// - Opening bracket "(" is inserted at position 0
    /// - Closing bracket ")" is added at the end
    /// - Total width increases by 2
    pub fn add_brackets(&mut self) {
        let bracket_structure_id =
            self.create_structure_context(vec!["bracket".to_string()], None, 0);

        // Shift all existing elements to make room for opening bracket
        for element in &mut self.elements {
            element.position += 1;
        }

        // Add opening bracket at the beginning
        self.elements.insert(
            0,
            LayoutElement {
                content: "(".to_string(),
                level: self.baseline,
                position: 0,
                structure_id: bracket_structure_id,
            },
        );

        // Add closing bracket at the end
        self.elements.push(LayoutElement {
            content: ")".to_string(),
            level: self.baseline,
            position: self.total_width + 1,
            structure_id: bracket_structure_id,
        });

        self.total_width += 2;
    }

    /// Merges another layout horizontally with an operator between them.
    ///
    /// Combines two mathematical expressions side-by-side with an operator (like +, -, *, /)
    /// in between. Handles bracket insertion for the right operand when required by
    /// operator precedence rules.
    ///
    /// # Arguments
    /// * `other` - The right-hand layout to merge
    /// * `operator` - The operator string to place between layouts (e.g., "+", "*")
    /// * `op_level` - Vertical level where the operator should be placed
    /// * `right_needs_brackets` - Whether to wrap the right operand in brackets
    ///
    /// # Layout Process
    /// 1. Optionally add brackets to right operand
    /// 2. Add operator with spacing at current width
    /// 3. Merge structural contexts from both layouts
    /// 4. Offset and add all elements from right layout
    /// 5. Update total width and level heights
    pub fn merge_horizontal(
        &mut self,
        mut other: LeveledLayout,
        operator: &str,
        op_level: i32,
        right_needs_brackets: bool,
    ) {
        if right_needs_brackets {
            other.add_brackets();
        }

        let current_width = self.total_width;
        let op_width = operator.len() + 2; // operator + spaces

        // Create operator structure context
        let op_structure_id = self.create_structure_context(
            vec!["operator".to_string(), operator.to_string()],
            None,
            0,
        );

        // Add operator with spacing
        self.elements.push(LayoutElement {
            content: format!(" {} ", operator),
            level: op_level,
            position: current_width,
            structure_id: op_structure_id,
        });

        // Merge contexts from other layout
        for (id, context) in other.contexts {
            self.contexts.insert(id, context);
        }

        // Add other elements with proper position offset
        for mut element in other.elements {
            element.position += current_width + op_width;
            self.elements.push(element);
        }

        self.total_width += op_width + other.total_width;

        // Merge level heights
        for (level, height) in other.level_heights {
            *self.level_heights.entry(level).or_insert(0) =
                *self.level_heights.get(&level).unwrap_or(&0).max(&height);
        }
    }

    /// Merges two layouts vertically to create a fraction (numerator/denominator).
    ///
    /// Creates a mathematical fraction by placing the numerator above a division line
    /// and the denominator below. Both numerator and denominator are centered relative
    /// to the division line for proper mathematical formatting.
    ///
    /// # Arguments
    /// * `num_layout` - Layout for the numerator (top part)
    /// * `den_layout` - Layout for the denominator (bottom part)
    /// * `division_level` - Level where the division line should be placed (typically baseline)
    ///
    /// # Layout Structure
    /// ```text
    ///   numerator     <- above division_level
    /// ─────────────   <- at division_level
    ///  denominator    <- below division_level
    /// ```
    ///
    /// # Centering Logic
    /// - Division line width = max(numerator_width, denominator_width, 3)
    /// - Numerator and denominator are centered relative to division line
    /// - All elements maintain their original structural contexts
    pub fn merge_vertical(
        &mut self,
        num_layout: LeveledLayout,
        den_layout: LeveledLayout,
        division_level: i32,
    ) {
        let max_width = num_layout.total_width.max(den_layout.total_width).max(3);

        // Create division structure context
        let div_structure_id = self.create_structure_context(vec!["division".to_string()], None, 1);

        self.elements.clear();

        // Merge contexts from both layouts
        for (id, context) in num_layout.contexts {
            self.contexts.insert(id, context);
        }
        for (id, context) in den_layout.contexts {
            self.contexts.insert(id, context);
        }

        // Calculate centering offsets for numerator and denominator
        let num_offset = if num_layout.total_width < max_width {
            (max_width - num_layout.total_width) / 2
        } else {
            0
        };

        let den_offset = if den_layout.total_width < max_width {
            (max_width - den_layout.total_width) / 2
        } else {
            0
        };

        // Add numerator elements with centering and structure isolation
        for mut element in num_layout.elements {
            element.position = num_offset + element.position;
            // Preserve original structure context to prevent interference
            self.elements.push(element);
        }

        // Add division line with its own structure
        self.elements.push(LayoutElement {
            content: "─".repeat(max_width),
            level: division_level,
            position: 0,
            structure_id: div_structure_id,
        });

        // Add denominator elements with centering and structure isolation
        for mut element in den_layout.elements {
            element.position = den_offset + element.position;
            // Preserve original structure context to prevent interference
            self.elements.push(element);
        }

        // Merge level heights properly
        self.level_heights.clear();

        // Add numerator levels as-is (they should already be positioned correctly)
        for (&level, &height) in &num_layout.level_heights {
            *self.level_heights.entry(level).or_insert(0) = height;
        }

        // Add denominator levels as-is (they should already be positioned correctly)
        for (&level, &height) in &den_layout.level_heights {
            *self.level_heights.entry(level).or_insert(0) = height;
        }

        // Add division line level
        *self.level_heights.entry(division_level).or_insert(0) = 1;

        self.total_width = max_width;
        self.baseline = division_level;
    }

    /// Merges an exponent layout directly (unused helper method).
    ///
    /// This is a simple merge that adds exponent elements without level adjustment.
    /// Currently unused in favor of the more sophisticated `merge_power_exponent` method.
    ///
    /// # Arguments
    /// * `exp_layout` - The exponent layout to merge
    #[allow(dead_code)]
    fn _merge_exponent(&mut self, exp_layout: LeveledLayout) {
        // Add exponent elements
        self.elements.extend(exp_layout.elements);

        // Merge level heights
        for (level, height) in exp_layout.level_heights {
            *self.level_heights.entry(level).or_insert(0) =
                *self.level_heights.get(&level).unwrap_or(&0).max(&height);
        }

        self.total_width += exp_layout.total_width;
    }

    /// Merges an exponent layout as a superscript to the current base.
    ///
    /// Positions the exponent above the baseline and to the right of the base expression.
    /// Handles level conflicts by adjusting exponent levels to ensure they appear above
    /// the base without interfering with existing layout elements.
    ///
    /// # Arguments
    /// * `exp_layout` - Layout containing the exponent expression
    ///
    /// # Layout Process
    /// 1. Calculate base width and baseline for positioning
    /// 2. Merge structural contexts from exponent
    /// 3. Find minimum level in exponent for offset calculation
    /// 4. Adjust all exponent levels to appear above base
    /// 5. Position exponent elements to the right of base
    /// 6. Update total width and level heights
    ///
    /// # Example
    /// ```text
    /// Before: "x"     Exponent: "2"
    /// After:  "x²"    (if Unicode) or "x" with "2" at higher level
    /// ```
    pub fn merge_power_exponent(&mut self, exp_layout: LeveledLayout) {
        let base_width = self.total_width;
        let base_baseline = self.baseline;

        // Create power structure context
        let _power_structure_id = self.create_structure_context(
            vec!["power".to_string(), "exponent".to_string()],
            None,
            2,
        );

        // Merge contexts from exponent layout
        for (id, context) in exp_layout.contexts {
            self.contexts.insert(id, context);
        }

        // Find min level in exponent to calculate proper offset
        let exp_min_level = *exp_layout.level_heights.keys().min().unwrap_or(&0);

        // Calculate offset to move all exponent levels above the base
        // Ensures exponent appears as superscript without level conflicts
        let level_offset = (base_baseline + 1) - exp_min_level;

        // Add exponent elements with level adjustment and structure isolation
        for mut element in exp_layout.elements {
            element.level += level_offset;
            element.position += base_width;
            // Preserve original structure context but update level
            self.elements.push(element);
        }

        // Merge level heights with offset
        for (level, height) in exp_layout.level_heights {
            *self.level_heights.entry(level + level_offset).or_insert(0) = height;
        }

        // Update total width to accommodate both base and exponent
        self.total_width = base_width + exp_layout.total_width;
    }

    /// Merges another layout inline (horizontally) without any operator or spacing.
    ///
    /// Directly concatenates the other layout to the right of the current layout.
    /// Used for combining function arguments, parenthetical content, or other
    /// expressions that should appear immediately adjacent.
    ///
    /// # Arguments
    /// * `other` - Layout to merge inline
    ///
    /// # Layout Process
    /// 1. Merge structural contexts
    /// 2. Offset all elements by current width
    /// 3. Add all elements to current layout
    /// 4. Merge level heights (taking maximum for each level)
    /// 5. Update total width
    pub fn merge_inline(&mut self, other: LeveledLayout) {
        let current_width = self.total_width;

        // Merge contexts from other layout
        for (id, context) in other.contexts {
            self.contexts.insert(id, context);
        }

        for mut element in other.elements {
            element.position += current_width;
            self.elements.push(element);
        }

        for (level, height) in other.level_heights {
            *self.level_heights.entry(level).or_insert(0) =
                *self.level_heights.get(&level).unwrap_or(&0).max(&height);
        }

        self.total_width += other.total_width;
    }

    /// Merges a function with potentially multi-line content inside parentheses.
    ///
    /// Handles mathematical functions like sin(x), ln(complex_expression), etc.
    /// Automatically detects whether the inner content spans multiple levels and
    /// formats accordingly - simple inline for single-level content, or structured
    /// multi-line layout for complex expressions.
    ///
    /// # Arguments
    /// * `func_name` - Name of the function (e.g., "sin", "ln", "exp")
    /// * `inner_layout` - Layout of the function's argument/content
    ///
    /// # Layout Strategies
    ///
    /// ## Single-line content:
    /// ```text
    /// sin(x + y)  <- All on baseline
    /// ```
    ///
    /// ## Multi-line content:
    /// ```text
    /// sin( x + y )  <- Function name and brackets at baseline
    ///      ───      <- Inner content preserves its level structure
    ///       z
    /// ```
    ///
    /// # Implementation Details
    /// - Detects multi-line by comparing min/max levels in inner layout
    /// - Single-line: Concatenates everything into one element
    /// - Multi-line: Preserves inner structure with proper offset positioning
    /// - Maintains structural isolation to prevent layout conflicts
    pub fn merge_function_with_multiline(&mut self, func_name: &str, inner_layout: LeveledLayout) {
        // Create function structure context
        let func_structure_id = self.create_structure_context(
            vec!["function".to_string(), func_name.to_string()],
            None,
            1,
        );

        // For multi-line content inside functions, we need special handling
        let min_level = *inner_layout.level_heights.keys().min().unwrap_or(&0);
        let max_level = *inner_layout.level_heights.keys().max().unwrap_or(&0);

        // Merge contexts from inner layout
        for (id, context) in inner_layout.contexts {
            self.contexts.insert(id, context);
        }

        // Check if inner layout has multiple levels (is truly multi-line)
        if min_level == max_level {
            // Single line - use simple inline approach
            let content = inner_layout
                .elements
                .iter()
                .map(|e| e.content.clone())
                .collect::<Vec<_>>()
                .join("");
            let func_with_content = format!("{}({})", func_name, content);

            self.elements.push(LayoutElement {
                content: func_with_content.clone(),
                level: self.baseline,
                position: self.total_width,
                structure_id: func_structure_id,
            });

            self.total_width += func_with_content.chars().count();
            self.level_heights.extend(inner_layout.level_heights);
            return;
        }

        // Multi-line case: preserve function structure with isolation
        let current_pos = self.total_width;

        // Add function name and opening parenthesis at baseline
        let opening = format!("{}(", func_name);
        self.elements.push(LayoutElement {
            content: opening.clone(),
            level: self.baseline,
            position: current_pos,
            structure_id: func_structure_id,
        });

        // Add inner elements with proper offset and structure isolation
        let func_offset = opening.chars().count();
        for mut element in inner_layout.elements {
            element.position = current_pos + func_offset + element.position;
            // Preserve original structure context to prevent interference
            self.elements.push(element);
        }

        // Add closing parenthesis at baseline
        let inner_width = inner_layout.total_width;
        self.elements.push(LayoutElement {
            content: ")".to_string(),
            level: self.baseline,
            position: current_pos + func_offset + inner_width,
            structure_id: func_structure_id,
        });

        // Update layout properties
        self.level_heights.extend(inner_layout.level_heights);
        self.total_width = current_pos + func_offset + inner_width + 1;
    }

    /// Renders the layout into a vector of strings representing the final mathematical expression.
    ///
    /// This is the core rendering method that converts the multi-level layout structure
    /// into human-readable mathematical notation. It handles proper alignment, spacing,
    /// and conflict resolution between different structural elements.
    ///
    /// # Returns
    /// Vector of strings where each string represents one line of the mathematical expression
    ///
    /// # Rendering Process
    ///
    /// ## 1. Level Collection and Sorting
    /// - Identifies all levels that contain actual content (non-empty elements)
    /// - Sorts levels from top to bottom (descending order: +2, +1, 0, -1, -2)
    ///
    /// ## 2. Element Positioning
    /// - Groups elements by structural families to prevent conflicts
    /// - Sorts elements within each level by structure family, then by position
    /// - Creates character arrays for each line with proper width
    ///
    /// ## 3. Conflict Resolution
    /// - Detects when multiple elements try to occupy the same position
    /// - Uses structural compatibility checking to resolve conflicts
    /// - Skips conflicting characters when structures are incompatible
    ///
    /// ## 4. Gap Management (Conservative Approach)
    /// - Only adds empty lines between levels with gaps > 2
    /// - Ensures tight rendering for fractions (numerator/line/denominator)
    /// - Preserves spacing for complex nested expressions
    ///
    /// # Example Output
    /// ```text
    /// For expression: x² + sin(y) / e^x + 1
    ///
    ///     2        x
    /// x  + sin(y) / e  + 1
    /// ```
    ///
    /// # Gap Reduction Logic
    /// - gap ≤ 2: No empty lines (tight mathematical formatting)
    /// - gap > 2: One empty line (prevents visual confusion)
    pub fn render(&self) -> Vec<String> {
        if self.elements.is_empty() {
            return vec![String::new()];
        }

        let _min_level = *self.level_heights.keys().min().unwrap_or(&0);
        let _max_level = *self.level_heights.keys().max().unwrap_or(&0);

        let mut lines = Vec::new();

        // Calculate the maximum width needed for proper alignment
        let max_width = self
            .elements
            .iter()
            .map(|e| e.position + e.content.chars().count())
            .max()
            .unwrap_or(0);

        // Group elements by structural families to prevent interference
        let _structural_families = self.group_by_structural_families();

        // Collect all levels that actually have content
        let mut levels_with_content: Vec<i32> = self
            .level_heights
            .keys()
            .filter(|&&level| {
                self.elements
                    .iter()
                    .any(|e| e.level == level && !e.content.trim().is_empty())
            })
            .cloned()
            .collect();
        levels_with_content.sort_by(|a, b| b.cmp(a)); // Sort descending (top to bottom)

        // Render only levels that have content, with conservative gap reduction
        for (i, level) in levels_with_content.iter().enumerate() {
            // Collect elements at this level, sorted by position and structure
            let mut level_elements: Vec<&LayoutElement> = self
                .elements
                .iter()
                .filter(|e| e.level == *level && !e.content.trim().is_empty())
                .collect();

            // Sort by structure family first, then by position to prevent conflicts
            level_elements.sort_by(|a, b| {
                let family_a = self.get_structure_family(a.structure_id);
                let family_b = self.get_structure_family(b.structure_id);
                family_a.cmp(&family_b).then(a.position.cmp(&b.position))
            });

            if level_elements.is_empty() {
                continue;
            }

            // Build line with structure-aware positioning
            let mut line_chars: Vec<char> = " ".repeat(max_width).chars().collect();

            for element in level_elements {
                let content = &element.content;

                if content.is_empty() {
                    continue;
                }

                let start_pos = element.position;
                let content_chars: Vec<char> = content.chars().collect();

                // Safely place each character with conflict detection
                for (i, &ch) in content_chars.iter().enumerate() {
                    let pos = start_pos + i;
                    if pos < line_chars.len() {
                        // Check for conflicts with different structural families
                        if line_chars[pos] != ' '
                            && !self.are_compatible_structures(element.structure_id, pos)
                        {
                            // Handle conflict by adjusting position or skipping
                            continue;
                        }
                        line_chars[pos] = ch;
                    }
                }
            }

            let line_str: String = line_chars.into_iter().collect();
            lines.push(line_str.trim_end().to_string());

            // DIVISION-AWARE GAP MANAGEMENT: Tight spacing for divisions, conservative for others
            if i < levels_with_content.len() - 1 {
                let current_level = *level;
                let next_level = levels_with_content[i + 1];
                let gap = (current_level - next_level).abs();

                // Check if we're in a division context by looking for division lines
                let has_division_line = self.elements.iter().any(|e| {
                    e.content.contains('─')
                        && (e.level == current_level
                            || e.level == next_level
                            || (e.level > next_level && e.level < current_level))
                });

                // For divisions: no gaps (tight formatting)
                // For other expressions: gaps only when > 2
                if !has_division_line && gap > 2 {
                    lines.push(String::new());
                }
            }
        }

        // Remove trailing empty lines
        while lines.last().map_or(false, |line| line.trim().is_empty()) {
            lines.pop();
        }

        if lines.is_empty() {
            vec![String::new()]
        } else {
            lines
        }
    }

    /// Groups layout elements by their structural families for conflict resolution.
    ///
    /// Elements belonging to the same structural family (sharing a common root structure)
    /// are grouped together. This enables the rendering system to detect and resolve
    /// conflicts between different mathematical constructs.
    ///
    /// # Returns
    /// HashMap mapping family root IDs to vectors of structure IDs in that family
    ///
    /// # Usage
    /// Used during rendering to ensure elements from different structural families
    /// don't interfere with each other's positioning and layout.
    fn group_by_structural_families(&self) -> std::collections::HashMap<usize, Vec<usize>> {
        let mut families = std::collections::HashMap::new();

        for element in &self.elements {
            let family_id = self.get_structure_family(element.structure_id);
            families
                .entry(family_id)
                .or_insert_with(Vec::new)
                .push(element.structure_id);
        }

        families
    }

    /// Finds the root structure ID for a given structure by traversing parent relationships.
    ///
    /// Walks up the structural hierarchy to find the topmost parent structure.
    /// This identifies which "family" a structure belongs to, enabling conflict
    /// detection between different mathematical constructs.
    ///
    /// # Arguments
    /// * `structure_id` - The structure ID to find the family root for
    ///
    /// # Returns
    /// The root structure ID of the family
    ///
    /// # Example
    /// For a complex expression like "sin(x/y)", the division structure and
    /// the sin function structure would have different family roots, preventing
    /// layout conflicts between them.
    fn get_structure_family(&self, structure_id: usize) -> usize {
        // Find the root structure ID by traversing parent relationships
        let mut current_id = structure_id;
        while let Some(context) = self.contexts.get(&current_id) {
            if let Some(parent_id) = context.parent_id {
                current_id = parent_id;
            } else {
                break;
            }
        }
        current_id
    }

    /// Checks if two structures can coexist at the same position without conflict.
    ///
    /// Currently implements a permissive policy allowing all structures to coexist.
    /// This method is designed to be enhanced with more sophisticated conflict
    /// detection logic as needed.
    ///
    /// # Arguments
    /// * `_structure_id` - ID of the structure being placed (currently unused)
    /// * `_position` - Position where the structure is being placed (currently unused)
    ///
    /// # Returns
    /// `true` if structures are compatible, `false` if they conflict
    ///
    /// # Future Enhancements
    /// Could be extended to:
    /// - Detect overlapping mathematical constructs
    /// - Prevent division lines from interfering with exponents
    /// - Resolve bracket placement conflicts
    /// - Handle complex nested expression conflicts
    fn are_compatible_structures(&self, _structure_id: usize, _position: usize) -> bool {
        // For now, allow all structures to coexist
        // This can be enhanced with more sophisticated conflict detection
        true
    }
}