/**
 * Code Review Engine - Markdown Reporter
 *
 * Generate Markdown format reports.
 */

import type { CodeIssue, ReportOptions, ReviewResult } from "../types.js";

export class MarkdownReporter {
	/**
	 * Generate Markdown report
	 */
	generate(result: ReviewResult, options: ReportOptions): string {
		const lines: string[] = [];

		// Header
		lines.push("# Code Review Report");
		lines.push("");
		lines.push(`**Review ID:** ${result.id}`);
		lines.push(`**Timestamp:** ${result.timestamp}`);
		lines.push(`**Duration:** ${result.durationMs}ms`);
		lines.push("");

		// Summary
		if (options.includeSummary !== false) {
			lines.push("## Summary");
			lines.push("");
			lines.push(`| Metric | Value |`);
			lines.push(`|--------|-------|`);
			lines.push(`| Files Reviewed | ${result.stats.filesReviewed} |`);
			lines.push(`| Lines Reviewed | ${result.stats.linesReviewed} |`);
			lines.push(`| Total Issues | ${result.summary.total} |`);
			lines.push(`| Errors | ${result.summary.errors} |`);
			lines.push(`| Warnings | ${result.summary.warnings} |`);
			lines.push(`| Info | ${result.summary.info} |`);
			lines.push(`| Hints | ${result.summary.hints} |`);
			lines.push("");
		}

		// Category breakdown
		if (Object.keys(result.summary.byCategory).length > 0) {
			lines.push("### Issues by Category");
			lines.push("");
			lines.push(`| Category | Count |`);
			lines.push(`|----------|-------|`);
			for (const [category, count] of Object.entries(
				result.summary.byCategory,
			)) {
				lines.push(`| ${category} | ${count} |`);
			}
			lines.push("");
		}

		// Issues
		if (result.issues.length > 0) {
			lines.push("## Issues");
			lines.push("");

			// Group issues
			const groupedIssues = options.groupByFile
				? this.groupByFile(result.issues)
				: options.groupBySeverity
					? this.groupBySeverity(result.issues)
					: [{ header: "", issues: result.issues }];

			for (const group of groupedIssues) {
				if (group.header) {
					lines.push(`### ${group.header}`);
					lines.push("");
				}

				for (const issue of group.issues) {
					lines.push(this.formatIssue(issue, options));
				}
			}
		} else {
			lines.push("## Issues");
			lines.push("");
			lines.push(
				"🎉 **No issues found!** Your code passed all automated checks.",
			);
			lines.push("");
		}

		// Footer
		lines.push("---");
		lines.push("");
		lines.push("*Generated by pi-harness-runtime Code Review Engine*");

		return lines.join("\n");
	}

	/**
	 * Format a single issue
	 */
	private formatIssue(issue: CodeIssue, options: ReportOptions): string {
		const lines: string[] = [];

		const severityEmoji = this.getSeverityEmoji(issue.severity);
		lines.push(`#### ${severityEmoji} ${issue.title}`);
		lines.push("");
		lines.push(`- **Severity:** ${issue.severity}`);
		lines.push(`- **Category:** ${issue.category}`);
		lines.push(
			`- **Location:** ${issue.file}${issue.line ? `:${issue.line}` : ""}`,
		);

		if (issue.rule) {
			lines.push(`- **Rule:** \`${issue.rule}\``);
		}

		lines.push("");
		lines.push(`${issue.message}`);
		lines.push("");

		if (issue.suggestion && options.includeSuggestions !== false) {
			lines.push(`> **Suggestion:** ${issue.suggestion}`);
			lines.push("");
		}

		if (issue.code && options.includeCode !== false) {
			lines.push("```");
			lines.push(issue.code);
			lines.push("```");
			lines.push("");
		}

		return lines.join("\n");
	}

	/**
	 * Get severity emoji
	 */
	private getSeverityEmoji(severity: string): string {
		switch (severity) {
			case "error":
				return "🔴";
			case "warning":
				return "🟡";
			case "info":
				return "🔵";
			case "hint":
				return "💡";
			default:
				return "⚪";
		}
	}

	/**
	 * Group issues by file
	 */
	private groupByFile(
		issues: CodeIssue[],
	): { header: string; issues: CodeIssue[] }[] {
		const groups = new Map<string, CodeIssue[]>();

		for (const issue of issues) {
			const existing = groups.get(issue.file);
			if (existing) {
				existing.push(issue);
			} else {
				groups.set(issue.file, [issue]);
			}
		}

		return Array.from(groups.entries()).map(([file, fileIssues]) => ({
			header: file,
			issues: fileIssues,
		}));
	}

	/**
	 * Group issues by severity
	 */
	private groupBySeverity(
		issues: CodeIssue[],
	): { header: string; issues: CodeIssue[] }[] {
		const groups = new Map<string, CodeIssue[]>();
		const order = ["error", "warning", "info", "hint"];

		for (const issue of issues) {
			const existing = groups.get(issue.severity);
			if (existing) {
				existing.push(issue);
			} else {
				groups.set(issue.severity, [issue]);
			}
		}

		return order
			.filter((s) => groups.has(s))
			.map((severity) => ({
				header: `${severity.charAt(0).toUpperCase() + severity.slice(1)}s`,
				issues: groups.get(severity)!,
			}));
	}
}