import type { MpcPhase } from "./utils.js";

export function phaseLabel(phase: MpcPhase): string {
	const labels: Record<MpcPhase, string> = {
		idle: "off",
		explore: "explore",
		dryrun: "dry-run",
		issues: "issues",
		backtrack: "backtrack",
		verified: "verified",
		execute: "execute",
	};
	return labels[phase];
}

export function buildPhasePrompt(phase: MpcPhase): string {
	switch (phase) {
		case "explore":
			return `[MPC MODE - PHASE 1: EXPLORATION]
Goal: Understand the codebase relevant to this task. Do NOT make any changes.
- Read files, grep for patterns, understand the structure
- Identify all files that will need to change
- Note dependencies, interfaces, test files
- End your response with exactly: "EXPLORATION COMPLETE: [one-sentence summary of what you found]"`;

		case "dryrun":
			return `[MPC MODE - PHASE 2: DRY RUN]
You have explored the codebase. Now mentally execute the task without actually doing it.
- Describe each edit you would make, step by step
- For each step, predict: what does the file look like after this change?
- Trace through call sites, imports, type signatures
- End your response with exactly: "DRY RUN COMPLETE: [numbered list of steps]"`;

		case "issues":
			return `[MPC MODE - PHASE 3: ISSUE DETECTION]
Review your dry run. Actively look for problems:
- Type errors that would result from your changes
- Broken imports or missing exports
- Tests that would fail
- Edge cases or missing error handling
- Incorrect assumptions about the codebase
List each issue as: "ISSUE N: [description] → [impact]"
If there are no problems, end with exactly: "NO ISSUES FOUND"`;

		case "backtrack":
			return `[MPC MODE - PHASE 4: BACKTRACK]
Issues were found in Phase 3. Revise your plan:
- Address each issue identified
- Adjust the step sequence if needed
- Re-verify your assumptions
End your response with exactly: "REVISED PLAN: [updated numbered steps]"`;

		case "verified":
			return `[MPC MODE - PHASE 5: VERIFIED PLAN]
Present the final verified plan in this format:

## Verified Plan

### Summary
[One paragraph: what this does and why]

### Assumptions Verified
- [assumption]: [how you verified it]

### Steps
1. **[File/Action]**: [what and why]
2. ...

### Potential Risks
- [any remaining unknowns or caveats]

### Confidence
[HIGH/MEDIUM/LOW]: [reason]`;

		case "execute":
			return `[MPC MODE - EXECUTING PLAN]
Execute the verified plan exactly as described. Follow the steps in order.`;

		default:
			return "";
	}
}