import * as vscode from 'vscode';
import { LinterRule } from './LinterRule';
import { LinterContext } from '../LinterContext';

export class IndentationRule implements LinterRule {
    
    public checkLine(line: string, rawLine: string, lineIdx: number, ctx: LinterContext, lines: string[]): void {
        if (rawLine.trim().length === 0) {return;}
        if (rawLine.includes('\t')) {return;}

        // Sobald wir in Klammern oder einem Multi-Line Import sind (Visual Alignment),
        // greift die 4-Leerzeichen-Regel nicht!
        if (ctx.parenStack.length > 0 || ctx.bracketStack.length > 0 || ctx.inImportBlock) {
            return;
        }

        const leadingSpacesMatch = rawLine.match(/^ +/);
        const spaceCount = leadingSpacesMatch ? leadingSpacesMatch[0].length : 0;

        if (spaceCount > 0 && spaceCount % 4 !== 0) {
            ctx.addDiag(
                lineIdx, 
                0, 
                spaceCount,
                `Invalid indentation (${spaceCount} spaces). Please use a multiple of 4. (Tip: Shift+Alt+F to auto-format)`, 
                vscode.DiagnosticSeverity.Warning
            );
        }
    }

    public checkEnd(lines: string[], ctx: LinterContext): void {
        // empty
    }
}