/**
 * Task Compiler - File Scope Assignment
 *
 * Assigns filesInScope and FileOwnership to each compiled task
 * based on the project structure and task type.
 */

import type {
	CompiledTask,
	FileOwnership,
	FileOwnershipMode,
	ProjectProfile,
	TaskCandidate,
	TaskType,
} from "./types.js";

/**
 * Assign file scope and ownership to each task candidate.
 *
 * File scope is determined by:
 * - Task type (implementation → source files, test → test files)
 * - Project structure (detected by Project Analyzer)
 * - Requirement goals and constraints
 */
export function assignFileScope(
	candidates: TaskCandidate[],
	project: ProjectProfile,
): CompiledTask[] {
	const __projectPath = project.projectPath;
	const sourceExts = detectSourceExtensions(project);
	const testExts = detectTestExtensions(project);

	return candidates.map((candidate) => {
		const filesInScope = inferFiles(candidate, project, sourceExts, testExts);
		const mode = getOwnershipMode(candidate.type);
		const ownership: FileOwnership = {
			taskId: candidate.id,
			include: filesInScope,
			exclude: getExclusions(candidate.type, project),
			mode,
		};

		return {
			id: candidate.id,
			jobId: "", // Set by compiler
			title: candidate.title,
			objective: candidate.objective,
			type: candidate.type,
			dependencies: candidate.roughDependencies,
			filesInScope,
			filesExclude: ownership.exclude,
			expectedOutputs: [], // Set by verification.ts
			acceptanceCriteria: candidate.criteria,
			requiredCapabilities: inferCapabilities(candidate.type),
			permittedCommands: [], // Set by command-policy.ts
			prohibitedCommands: [], // Set by command-policy.ts
			preferredProvider: undefined, // Set by compiler.ts
			estimatedComplexity: candidate.estimatedComplexity,
			fileOwnership: ownership,
			priority: candidate.priority,
		};
	});
}

// ─── File inference by task type ───────────────────────────────────────

function inferFiles(
	candidate: TaskCandidate,
	project: ProjectProfile,
	_sourceExts: string[],
	testExts: string[],
): string[] {
	const { type, objective } = candidate;
	const base = project.projectPath;

	switch (type) {
		case "analysis": {
			return [`${base}/src/**`];
		}

		case "design": {
			return [`${base}/src/**/*.ts`, `${base}/docs/**`];
		}

		case "implementation": {
			// Default to all source files; narrow by extracting file mentions from objective
			const mentions = extractFileMentions(objective);
			if (mentions.length > 0) return mentions;
			return [`${base}/src/**`];
		}

		case "test": {
			if (testExts.length > 0)
				return [`${base}/test/**`, `${base}/**/*.test.*`];
			return [`${base}/**/*.test.*`, `${base}/**/*.spec.*`];
		}

		case "e2e_test": {
			return [`${base}/**/*.e2e.*`, `${base}/e2e/**`];
		}

		case "review": {
			// Review reads everything that's been modified
			return [`${base}/src/**`];
		}

		case "repair": {
			// Repair targets whatever the review flagged
			const mentions = extractFileMentions(objective);
			return mentions.length > 0 ? mentions : [`${base}/src/**`];
		}

		case "documentation": {
			return [`${base}/README.md`, `${base}/docs/**`, `${base}/src/**/*.md`];
		}

		default: {
			return [`${base}/src/**`];
		}
	}
}

// ─── Extract file mentions from objective text ──────────────────────────

function extractFileMentions(text: string): string[] {
	// Match common file/directory patterns in natural language:
	// - "src/components/Button.tsx"
	// - "packages/foo/src/"
	// - "test/user.test.ts"
	const pattern =
		/(?:src|test|packages?|apps?|lib|components?|hooks?|utils|docs?)[/\\][^\s"']+/gi;
	const matches = text.match(pattern);
	if (!matches) return [];
	// Deduplicate and return
	return [...new Set(matches)];
}

// ─── Ownership mode ────────────────────────────────────────────────────

function getOwnershipMode(type: TaskType): FileOwnershipMode {
	// Parallel tasks with "exclusive" mode cannot modify the same files
	switch (type) {
		case "implementation":
		case "test":
		case "e2e_test":
		case "repair":
			return "exclusive";
		case "analysis":
		case "design":
		case "review":
		case "documentation":
			return "shared_read";
		default:
			return "shared_read";
	}
}

// ─── Exclusions ────────────────────────────────────────────────────────

function getExclusions(_type: TaskType, project: ProjectProfile): string[] {
	const exclusions: string[] = [
		// Never touch these regardless of task type
		"**/node_modules/**",
		"**/dist/**",
		"**/.git/**",
		"**/coverage/**",
		"**/build/**",
	];

	// Add project-specific exclusions from rules
	if (project.rules) {
		for (const rule of project.rules) {
			if (rule.section === "scope" || rule.section === "files") {
				// Rules may specify excluded patterns
			}
		}
	}

	return exclusions;
}

// ─── Capability inference ───────────────────────────────────────────────

function inferCapabilities(type: TaskType): string[] {
	const caps: Record<TaskType, string[]> = {
		analysis: ["plan", "analysis"],
		design: ["plan", "analysis"],
		implementation: ["code"],
		test: ["code", "test"],
		e2e_test: ["code", "e2e"],
		review: ["review"],
		repair: ["code", "debug"],
		documentation: ["code"],
	};
	return caps[type] ?? ["code"];
}

// ─── Extension detection ─────────────────────────────────────────────────

function detectSourceExtensions(project: ProjectProfile): string[] {
	const frameworks = project.frameworks ?? [];
	const exts = new Set<string>(["ts", "tsx", "js", "jsx"]);

	if (frameworks.some((f) => /typescript|ts|tsx/i.test(f.name))) {
		exts.add("ts");
		exts.add("tsx");
	}
	if (frameworks.some((f) => /react|next\.?js|vue|svelte/i.test(f.name))) {
		exts.add("jsx");
		exts.add("tsx");
	}
	if (frameworks.some((f) => /python|flask|django|fastapi/i.test(f.name))) {
		exts.add("py");
	}
	if (frameworks.some((f) => /frappe|erpnext/i.test(f.name))) {
		exts.add("py");
		exts.add("js");
	}

	return [...exts];
}

function detectTestExtensions(project: ProjectProfile): string[] {
	const frameworks = project.frameworks ?? [];
	const testCaps = project.testCapabilities ?? [];
	const exts = new Set<string>();

	if (
		frameworks.some((f) =>
			/playwright|cypress|selenium|nightwatch/i.test(f.name),
		) ||
		testCaps.some((t) =>
			/playwright|cypress|selenium|nightwatch/i.test(t.runner),
		)
	) {
		exts.add("e2e.ts");
	}

	return [...exts];
}