import { execSync } from "node:child_process";
import { Decision, DecisionCategory, Alternative, confidenceToLevel } from "../types/decisions.js";
import { CIAgentConfig } from "../types/config.js";
import { CommitBuilder, DecisionCommitInput } from "./commit-builder.js";
import { CommitDecision } from "../types/commit-meta.js";

export interface DecisionInput {
  decision: string;
  rationale: string;
  confidence: number;
  category: DecisionCategory;
  alternatives_considered: Alternative[];
  phase?: string;
  task?: string;
}

export interface DecisionResult {
  decision: Decision;
  escalated: boolean;
  reason?: string;
  commitMessage?: string;
}

export class DecisionEngine {
  private config: CIAgentConfig;
  private projectPath: string;
  private currentPhase: number;
  private currentMilestone: string;
  private decisionCounter: number;

  constructor(config: CIAgentConfig, projectPath: string, milestone: string = "v1.0") {
    this.config = config;
    this.projectPath = projectPath;
    this.currentPhase = 0;
    this.currentMilestone = milestone;
    this.decisionCounter = 0;
  }

  setPhase(phase: number): void {
    this.currentPhase = phase;
  }

  setMilestone(milestone: string): void {
    this.currentMilestone = milestone;
  }

  makeDecision(input: DecisionInput): DecisionResult {
    const id = `D-${String(++this.decisionCounter).padStart(3, "0")}`;
    const threshold = this.config.autonomy.decision_confidence_threshold;

    const decision: Decision = {
      id,
      timestamp: new Date().toISOString(),
      decision: input.decision,
      rationale: input.rationale,
      confidence: input.confidence,
      category: input.category,
      alternatives_considered: input.alternatives_considered,
      human_override: null,
      phase: input.phase,
      task: input.task,
    };

    const commitDecision: CommitDecision = {
      id,
      decision: input.decision,
      rationale: input.rationale,
      confidence: input.confidence,
      alternatives: input.alternatives_considered.map((a) => a.option),
    };

    const confidenceLevel = confidenceToLevel(input.confidence);

    const escalated = input.confidence < threshold;

    let commitMessage: string | undefined;
    if (this.config.git.auto_commit) {
      commitMessage = CommitBuilder.buildDecisionCommit({
        phase: this.currentPhase,
        milestone: this.currentMilestone,
        subject: input.decision,
        decisions: [commitDecision],
      });
    }

    if (escalated) {
      return {
        decision,
        escalated: true,
        reason: `Confidence ${input.confidence.toFixed(2)} below threshold ${threshold} (${confidenceLevel})`,
        commitMessage,
      };
    }

    return { decision, escalated: false, commitMessage };
  }

  makeHighConfidenceDecision(
    decision: string,
    rationale: string,
    category: DecisionCategory,
    alternatives: Alternative[] = []
  ): DecisionResult {
    return this.makeDecision({
      decision,
      rationale,
      confidence: 0.95,
      category,
      alternatives_considered: alternatives,
    });
  }

  makeMediumConfidenceDecision(
    decision: string,
    rationale: string,
    category: DecisionCategory,
    alternatives: Alternative[] = []
  ): DecisionResult {
    return this.makeDecision({
      decision,
      rationale,
      confidence: 0.7,
      category,
      alternatives_considered: alternatives,
    });
  }

  shouldAutoDecide(confidence: number): boolean {
    return confidence >= this.config.autonomy.decision_confidence_threshold;
  }

  isIrreversibleAction(action: string): boolean {
    return this.config.autonomy.escalation_hooks.some((hook) =>
      action.toLowerCase().includes(hook.toLowerCase())
    );
  }

  commitDecision(commitMessage: string): boolean {
    if (!this.config.git.auto_commit) return false;
    try {
      execSync(`git add -A && git commit -m "${commitMessage.replace(/"/g, '\\"')}" --allow-empty`, {
        cwd: this.projectPath,
        stdio: "pipe",
      });
      return true;
    } catch {
      return false;
    }
  }
}