feat: Implement dispute flow with database schema and API endpoints

backend/src/disputes/dispute-service.js

@@ -0,0 +1,68 @@
+import { DB } from '../db/index.js';
+
+export class DisputeService {
+  constructor(db) {
+    this.db = db;
+  }
+
+  async createDispute(disputeData) {
+    const { deal_id, opened_by_user_id, reason_code, summary, requested_outcome } = disputeData;
+    
+    const result = await this.db.query(
+      `INSERT INTO disputes (deal_id, opened_by_user_id, reason_code, summary, requested_outcome) 
+       VALUES (?, ?, ?, ?, ?)`,
+      [deal_id, opened_by_user_id, reason_code, summary, requested_outcome]
+    );
+    
+    const disputeId = result.insertId;
+    return await this.getDisputeById(disputeId);
+  }
+
+  async getDisputeById(id) {
+    const [rows] = await this.db.query('SELECT * FROM disputes WHERE id = ?', [id]);
+    return rows.length > 0 ? rows[0] : null;
+  }
+
+  async updateDisputeStatus(disputeId, status, updatedByUserId) {
+    await this.db.query(
+      'UPDATE disputes SET status = ?, updated_at = CURRENT_TIMESTAMP WHERE id = ?',
+      [status, disputeId]
+    );
+    
+    // Log the status change as an event
+    await this.logDisputeEvent(disputeId, 'status_change', updatedByUserId, { 
+      old_status: 'open', 
+      new_status: status 
+    });
+  }
+
+  async addEvidence(disputeId, userId, evidenceData) {
+    // Log the evidence addition as an event
+    await this.logDisputeEvent(disputeId, 'evidence_added', userId, evidenceData);
+  }
+
+  async resolveDispute(disputeId, resolvedByUserId, decision, reason) {
+    await this.db.query(
+      `UPDATE disputes 
+       SET status = 'resolved', final_decision = ?, final_reason = ?, decided_by_user_id = ?, decided_at = CURRENT_TIMESTAMP 
+       WHERE id = ?`,
+      [decision, reason, resolvedByUserId, disputeId]
+    );
+    
+    // Log the resolution as an event
+    await this.logDisputeEvent(disputeId, 'resolved', resolvedByUserId, { decision, reason });
+  }
+
+  async logDisputeEvent(disputeId, eventType, actorUserId, payload) {
+    await this.db.query(
+      `INSERT INTO dispute_events (dispute_id, event_type, actor_user_id, payload_json) 
+       VALUES (?, ?, ?, ?)`,
+      [disputeId, eventType, actorUserId, JSON.stringify(payload)]
+    );
+  }
+
+  async getDisputeEvents(disputeId) {
+    const [rows] = await this.db.query('SELECT * FROM dispute_events WHERE dispute_id = ? ORDER BY created_at ASC', [disputeId]);
+    return rows;
+  }
+}

backend/src/disputes/dispute-service.ts

@@ -0,0 +1,67 @@
+import { DB } from '../db';
+import { Dispute, DisputeEvent, DisputeStatus, DisputeReasonCode, DisputeOutcome } from './types';
+
+export class DisputeService {
+  constructor(private db: DB) {}
+
+  async createDispute(disputeData: Omit<Dispute, 'id' | 'status' | 'created_at' | 'updated_at'>): Promise<Dispute> {
+    const { deal_id, opened_by_user_id, reason_code, summary, requested_outcome } = disputeData;
+    
+    const result = await this.db.query(
+      `INSERT INTO disputes (deal_id, opened_by_user_id, reason_code, summary, requested_outcome) 
+       VALUES (?, ?, ?, ?, ?)`,
+      [deal_id, opened_by_user_id, reason_code, summary, requested_outcome]
+    );
+    
+    const disputeId = result.insertId;
+    return await this.getDisputeById(disputeId);
+  }
+
+  async getDisputeById(id: number): Promise<Dispute | null> {
+    const [rows] = await this.db.query('SELECT * FROM disputes WHERE id = ?', [id]);
+    return rows.length > 0 ? rows[0] as Dispute : null;
+  }
+
+  async updateDisputeStatus(disputeId: number, status: DisputeStatus, updatedByUserId: number): Promise<void> {
+    await this.db.query(
+      'UPDATE disputes SET status = ?, updated_at = CURRENT_TIMESTAMP WHERE id = ?',
+      [status, disputeId]
+    );
+    
+    // Log the status change as an event
+    await this.logDisputeEvent(disputeId, 'status_change', updatedByUserId, { 
+      old_status: 'open', 
+      new_status: status 
+    });
+  }
+
+  async addEvidence(disputeId: number, userId: number, evidenceData: any): Promise<void> {
+    // Log the evidence addition as an event
+    await this.logDisputeEvent(disputeId, 'evidence_added', userId, evidenceData);
+  }
+
+  async resolveDispute(disputeId: number, resolvedByUserId: number, decision: DisputeOutcome, reason: string): Promise<void> {
+    await this.db.query(
+      `UPDATE disputes 
+       SET status = 'resolved', final_decision = ?, final_reason = ?, decided_by_user_id = ?, decided_at = CURRENT_TIMESTAMP 
+       WHERE id = ?`,
+      [decision, reason, resolvedByUserId, disputeId]
+    );
+    
+    // Log the resolution as an event
+    await this.logDisputeEvent(disputeId, 'resolved', resolvedByUserId, { decision, reason });
+  }
+
+  async logDisputeEvent(disputeId: number, eventType: string, actorUserId: number, payload: any): Promise<void> {
+    await this.db.query(
+      `INSERT INTO dispute_events (dispute_id, event_type, actor_user_id, payload_json) 
+       VALUES (?, ?, ?, ?)`,
+      [disputeId, eventType, actorUserId, JSON.stringify(payload)]
+    );
+  }
+
+  async getDisputeEvents(disputeId: number): Promise<DisputeEvent[]> {
+    const [rows] = await this.db.query('SELECT * FROM dispute_events WHERE dispute_id = ? ORDER BY created_at ASC', [disputeId]);
+    return rows as DisputeEvent[];
+  }
+}

backend/src/disputes/index.ts

@@ -0,0 +1,2 @@
+export * from './dispute-service';
+export * from './types';

backend/src/disputes/types.js

@@ -0,0 +1,51 @@
+export const DisputeStatus = {
+  OPEN: 'open',
+  EVIDENCE: 'evidence',
+  MEDIATION: 'mediation',
+  RESOLVED: 'resolved',
+  CANCELLED: 'cancelled'
+};
+
+export const DisputeReasonCode = {
+  NO_SHOW: 'NO_SHOW',
+  QUALITY_ISSUE: 'QUALITY_ISSUE',
+  PAYMENT_DISPUTE: 'PAYMENT_DISPUTE',
+  ABUSE: 'ABUSE',
+  OTHER: 'OTHER'
+};
+
+export const DisputeOutcome = {
+  REFUND: 'refund',
+  PARTIAL_REFUND: 'partial_refund',
+  COMPLETE_WORK: 'complete_work',
+  OTHER: 'other'
+};
+
+export class Dispute {
+  constructor(id, deal_id, opened_by_user_id, status, reason_code, summary, requested_outcome, final_decision = null, final_reason = null, decided_by_user_id = null, decided_at = null, created_at, updated_at) {
+    this.id = id;
+    this.deal_id = deal_id;
+    this.opened_by_user_id = opened_by_user_id;
+    this.status = status;
+    this.reason_code = reason_code;
+    this.summary = summary;
+    this.requested_outcome = requested_outcome;
+    this.final_decision = final_decision;
+    this.final_reason = final_reason;
+    this.decided_by_user_id = decided_by_user_id;
+    this.decided_at = decided_at;
+    this.created_at = created_at;
+    this.updated_at = updated_at;
+  }
+}
+
+export class DisputeEvent {
+  constructor(id, dispute_id, event_type, actor_user_id, payload_json, created_at) {
+    this.id = id;
+    this.dispute_id = dispute_id;
+    this.event_type = event_type;
+    this.actor_user_id = actor_user_id;
+    this.payload_json = payload_json;
+    this.created_at = created_at;
+  }
+}

backend/src/disputes/types.ts

@@ -0,0 +1,30 @@
+export type DisputeStatus = 'open' | 'evidence' | 'mediation' | 'resolved' | 'cancelled';
+
+export type DisputeReasonCode = 'NO_SHOW' | 'QUALITY_ISSUE' | 'PAYMENT_DISPUTE' | 'ABUSE' | 'OTHER';
+
+export type DisputeOutcome = 'refund' | 'partial_refund' | 'complete_work' | 'other';
+
+export interface Dispute {
+  id: number;
+  deal_id: number;
+  opened_by_user_id: number;
+  status: DisputeStatus;
+  reason_code: DisputeReasonCode;
+  summary: string;
+  requested_outcome: DisputeOutcome;
+  final_decision?: DisputeOutcome | null;
+  final_reason?: string | null;
+  decided_by_user_id?: number | null;
+  decided_at?: string | null;
+  created_at: string;
+  updated_at: string;
+}
+
+export interface DisputeEvent {
+  id: number;
+  dispute_id: number;
+  event_type: string;
+  actor_user_id: number;
+  payload_json: string;
+  created_at: string;
+}