import * as fs from 'fs';
import * as path from 'path';

export interface CommandParameter {
    name: string;
    type: string;
    required: boolean;
    defaultValue?: string;
}

export interface CommandInfo {
    name: string;
    description: string;
    parameters: CommandParameter[];
    example?: string;
}

export class CommandParser {
    private projectRoot: string;

    constructor(projectRoot: string) {
        this.projectRoot = projectRoot;
    }

    /**
     * Parse project.godot file to extract command directories
     */
    private parseProjectGodot(): string[] {
        const projectGodotPath = path.join(this.projectRoot, 'project.godot');
        
        if (!fs.existsSync(projectGodotPath)) {
            console.warn('project.godot not found, using default command directories');
            return [
                'res://addons/escoria-core/game/core-scripts/esc/commands',
                'res://addons/escoria-ui-return-monkey-island/esc/commands',
                'res://addons/escoria-ui-return-monkey-island-dialog-simple/commands'
            ];
        }

        const content = fs.readFileSync(projectGodotPath, 'utf8');
        const lines = content.split('\n');
        
        let inEscoriaSection = false;
        let commandDirectories: string[] = [];

        for (const line of lines) {
            const trimmedLine = line.trim();
            
            if (trimmedLine === '[escoria]') {
                inEscoriaSection = true;
                continue;
            }
            
            if (inEscoriaSection && trimmedLine.startsWith('[')) {
                break; // End of escoria section
            }
            
            if (inEscoriaSection && trimmedLine.startsWith('main/command_directories=')) {
                // Parse the array format: ["path1", "path2", "path3"]
                const arrayMatch = trimmedLine.match(/main\/command_directories=\[(.*)\]/);
                if (arrayMatch) {
                    const pathsString = arrayMatch[1];
                    // Extract quoted paths
                    const pathMatches = pathsString.match(/"([^"]+)"/g);
                    if (pathMatches) {
                        commandDirectories = pathMatches.map(match => match.slice(1, -1)); // Remove quotes
                    }
                }
                break;
            }
        }

        return commandDirectories.length > 0 ? commandDirectories : [
            'res://addons/escoria-core/game/core-scripts/esc/commands',
            'res://addons/escoria-ui-return-monkey-island/esc/commands',
            'res://addons/escoria-ui-return-monkey-island-dialog-simple/commands'
        ];
    }

    /**
     * Convert res:// path to actual filesystem path
     */
    private resPathToFsPath(resPath: string): string {
        if (resPath.startsWith('res://')) {
            return path.join(this.projectRoot, resPath.substring(6));
        }
        return path.join(this.projectRoot, resPath);
    }

    /**
     * Parse a single command file to extract command information
     */
    private parseCommandFile(filePath: string): CommandInfo | null {
        try {
            const content = fs.readFileSync(filePath, 'utf8');
            const lines = content.split('\n');
            
            // Extract command name from filename
            const fileName = path.basename(filePath, '.gd');
            const commandName = fileName;
            
            // Parse description from comments
            let description = '';
            let parameters: CommandParameter[] = [];
            let example = '';
            
            let inParametersSection = false;
            let inExampleSection = false;
            let foundFirstDescription = false;
            
            for (let i = 0; i < lines.length; i++) {
                const line = lines[i].trim();
                
                // Skip empty lines
                if (!line) {
                    continue;
                }
                
                // Extract main description (first comment block)
                if (line.startsWith('# `') && line.includes('`')) {
                    const match = line.match(/# `([^`]+)`/);
                    if (match) {
                        description = match[1];
                        foundFirstDescription = true;
                    }
                    continue;
                }
                
                // Look for description in subsequent comment lines (before parameters section)
                if (line.startsWith('#') && !inParametersSection && !inExampleSection) {
                    const cleanLine = line.replace(/^#\s*/, '');
                    
                    // Skip lines that are clearly not part of the main description
                    if (cleanLine.startsWith('**') || cleanLine.startsWith('@') || 
                        cleanLine.startsWith('Example:') || cleanLine.startsWith('e.g.') ||
                        cleanLine.includes('*') && cleanLine.includes(':') ||
                        cleanLine.includes('Constructor') || cleanLine.includes('Use look-ahead') ||
                        cleanLine.includes('Return the descriptor') || cleanLine.includes('Validate whether') ||
                        cleanLine.includes('Run the command') || cleanLine.includes('Function called when')) {
                        continue;
                    }
                    
                    // If we haven't found the first description yet, this might be it
                    if (!foundFirstDescription && cleanLine) {
                        description = cleanLine;
                        foundFirstDescription = true;
                        continue;
                    }
                    
                    // If we have a description and this line looks like continuation
                    if (foundFirstDescription && cleanLine && !cleanLine.includes('*')) {
                        // Stop if we hit code-related content
                        if (cleanLine.includes('Constructor') || cleanLine.includes('Use look-ahead') ||
                            cleanLine.includes('Return the descriptor') || cleanLine.includes('Validate whether') ||
                            cleanLine.includes('Run the command') || cleanLine.includes('Function called when')) {
                            break;
                        }
                        description += ' ' + cleanLine;
                    }
                    continue;
                }
                
                // Check for parameters section
                if (line.includes('**Parameters**')) {
                    inParametersSection = true;
                    inExampleSection = false;
                    continue;
                }
                
                // Check for example section
                if (line.includes('Example:')) {
                    inParametersSection = false;
                    inExampleSection = true;
                    const exampleMatch = line.match(/Example:\s*(.+)/);
                    if (exampleMatch) {
                        example = exampleMatch[1];
                    }
                    continue;
                }
                
                // Parse parameters (support both # - *param*: and # * *param*: formats)
                if (inParametersSection && (line.includes('# - *') || line.includes('# * *'))) {
                    const paramMatch = line.match(/#\s*[-*]\s*\*([^*]+)\*:\s*(.+)/);
                    if (paramMatch) {
                        const paramName = paramMatch[1].trim();
                        const paramDesc = paramMatch[2].trim();
                        
                        // Try to determine if parameter is required
                        const isRequired = !paramDesc.includes('default:') && !paramDesc.includes('(default:');
                        
                        // Extract default value if present
                        let defaultValue: string | undefined;
                        const defaultMatch = paramDesc.match(/\(default:\s*([^)]+)\)/);
                        if (defaultMatch) {
                            defaultValue = defaultMatch[1].trim();
                        }
                        
                        // Determine parameter type from description
                        let paramType = 'string';
                        if (paramDesc.includes('boolean') || paramDesc.includes('true') || paramDesc.includes('false')) {
                            paramType = 'boolean';
                        } else if (paramDesc.includes('number') || paramDesc.includes('int') || paramDesc.includes('float')) {
                            paramType = 'number';
                        }
                        
                        parameters.push({
                            name: paramName,
                            type: paramType,
                            required: isRequired,
                            defaultValue: defaultValue
                        });
                    }
                    continue;
                }
                
                // Parse configure() method to get more accurate parameter info
                if (line.includes('func configure()') && i + 5 < lines.length) {
                    // Look for ESCCommandArgumentDescriptor in the next few lines
                    for (let j = i + 1; j < Math.min(i + 15, lines.length); j++) {
                        const configLine = lines[j].trim();
                        if (configLine.includes('ESCCommandArgumentDescriptor.new(')) {
                            // Parse the descriptor parameters
                            const descriptorMatch = configLine.match(/ESCCommandArgumentDescriptor\.new\(\s*(\d+)/);
                            if (descriptorMatch) {
                                const minArgs = parseInt(descriptorMatch[1]);
                                
                                // Look for type arrays, defaults, and required flags in subsequent lines
                                let types: string[] = [];
                                let defaults: string[] = [];
                                let requiredFlags: boolean[] = [];
                                
                                for (let k = j + 1; k < Math.min(j + 10, lines.length); k++) {
                                    const typeLine = lines[k].trim();
                                    
                                    // Extract types array
                                    if (typeLine.includes('TYPE_') && typeLine.includes('[')) {
                                        const typeMatch = typeLine.match(/\[([^\]]+)\]/);
                                        if (typeMatch) {
                                            types = typeMatch[1].split(',').map(t => t.trim());
                                        }
                                    }
                                    
                                    // Extract defaults array
                                    if (typeLine.includes('null') && typeLine.includes('[') && !typeLine.includes('TYPE_')) {
                                        const defaultMatch = typeLine.match(/\[([^\]]+)\]/);
                                        if (defaultMatch) {
                                            defaults = defaultMatch[1].split(',').map(d => d.trim());
                                        }
                                    }
                                    
                                    // Extract required flags array (look for true/false pattern)
                                    if (typeLine.includes('true') && typeLine.includes('false') && typeLine.includes('[') && !typeLine.includes('TYPE_')) {
                                        const requiredMatch = typeLine.match(/\[([^\]]+)\]/);
                                        if (requiredMatch) {
                                            requiredFlags = requiredMatch[1].split(',').map(f => f.trim() === 'true');
                                        }
                                    }
                                }
                                
                                // Update or create parameters with accurate information
                                const maxParams = Math.max(types.length, defaults.length);
                                const newParameters: CommandParameter[] = [];
                                
                                // Store original parameters from comments for name preservation
                                const originalParams = [...parameters];
                                
                                for (let p = 0; p < maxParams; p++) {
                                    const type = types[p] || 'TYPE_STRING';
                                    const defaultValue = defaults[p] || 'null';
                                    // If requiredFlags array is not provided, use minArgs to determine required parameters
                                    const isRequired = p < minArgs || (requiredFlags[p] !== undefined ? requiredFlags[p] : p < minArgs);
                                    
                                    // Convert Godot types to readable types
                                    let paramType = 'string';
                                    if (type.includes('TYPE_BOOL')) {
                                        paramType = 'boolean';
                                    } else if (type.includes('TYPE_INT') || type.includes('TYPE_FLOAT')) {
                                        paramType = 'number';
                                    } else if (type.includes('TYPE_STRING')) {
                                        paramType = 'string';
                                    }
                                    
                                    // Try to get parameter name from comments if available, otherwise generate one
                                    let paramName = `param${p + 1}`;
                                    if (p < originalParams.length && originalParams[p] && originalParams[p].name !== `param${p + 1}`) {
                                        paramName = originalParams[p].name;
                                    }
                                    
                                    newParameters.push({
                                        name: paramName,
                                        type: paramType,
                                        required: isRequired,
                                        defaultValue: defaultValue !== 'null' ? defaultValue : undefined
                                    });
                                }
                                
                                // Replace parameters with the new ones from configure method
                                parameters = newParameters;
                            }
                            break;
                        }
                    }
                    break;
                }
            }
            
            // If we couldn't parse parameters from comments, try to infer from configure method
            if (parameters.length === 0) {
                // Look for configure method and try to extract parameter count
                const configureMatch = content.match(/func configure\(\)[^}]*ESCCommandArgumentDescriptor\.new\(\s*(\d+)/);
                if (configureMatch) {
                    const paramCount = parseInt(configureMatch[1]);
                    for (let i = 0; i < paramCount; i++) {
                        parameters.push({
                            name: `param${i + 1}`,
                            type: 'string',
                            required: true
                        });
                    }
                }
            }
            
            // Clean up description - remove extra whitespace and fix common issues
            if (description) {
                description = description.trim();
                
                // Remove extra whitespace
                description = description.replace(/\s+/g, ' ');
                
                // Truncate if too long (keep first sentence or first 200 chars)
                const firstSentence = description.split('.')[0];
                if (firstSentence.length < 200 && firstSentence.length > 20) {
                    description = firstSentence + '.';
                } else if (description.length > 200) {
                    description = description.substring(0, 200).trim() + '...';
                }
                
                // If description is just the command name, try to get a better one
                if (description === commandName || description === `${commandName} command`) {
                    description = `${commandName} command`;
                }
            }
            
            return {
                name: commandName,
                description: description || `${commandName} command`,
                parameters: parameters,
                example: example
            };
            
        } catch (error) {
            console.error(`Error parsing command file ${filePath}:`, error);
            return null;
        }
    }

    /**
     * Parse all command files from the specified directories
     */
    public parseCommands(): CommandInfo[] {
        const commandDirectories = this.parseProjectGodot();
        const commands: CommandInfo[] = [];
        
        for (const dir of commandDirectories) {
            const fsPath = this.resPathToFsPath(dir);
            
            if (!fs.existsSync(fsPath)) {
                console.warn(`Command directory not found: ${fsPath}`);
                continue;
            }
            
            try {
                const files = fs.readdirSync(fsPath);
                const gdFiles = files.filter(file => file.endsWith('.gd') && !file.endsWith('.gd.uid'));
                
                for (const file of gdFiles) {
                    const filePath = path.join(fsPath, file);
                    const commandInfo = this.parseCommandFile(filePath);
                    
                    if (commandInfo) {
                        commands.push(commandInfo);
                    }
                }
            } catch (error) {
                console.error(`Error reading directory ${fsPath}:`, error);
            }
        }
        
        // Sort commands alphabetically
        commands.sort((a, b) => a.name.localeCompare(b.name));
        
        return commands;
    }

    /**
     * Get commands in the format expected by the VSCode extension
     */
    public getCommandsForExtension(): Array<{name: string, description: string, parameters: CommandParameter[]}> {
        const commands = this.parseCommands();
        
        return commands.map(cmd => ({
            name: cmd.name,
            description: cmd.description,
            parameters: cmd.parameters
        }));
    }
}