import type { SCUMConfigRead, SCUMFeatureKey, SCUMFeatureMigrationAuthority, SCUMFeatureMigrationStatus, SCUMGiftGrant, SCUMMigrationRecord, SCUMPlayer, SCUMPlayerProfile, SCUMPlayerRisk, SCUMPlayerSession, SCUMStatePatch, SCUMTrajectory, SCUMTrajectoryPoint } from "./contracts.js";
import { configurationCatalog } from "./schemas.js";

export function transitionalReadOnly<T extends Record<string, unknown>>(payload: T, recordedAt: string, sourceRecordId?: string): SCUMMigrationRecord<T> { return { provenance: "transitional-read-only", readOnly: true, payload, recordedAt, sourceRecordId }; }
export function pluginOwned<T extends Record<string, unknown>>(payload: T, recordedAt: string): SCUMMigrationRecord<T> { return { provenance: "plugin", readOnly: false, payload, recordedAt }; }

// The authority flag is exact-server. Missing, duplicate, or
// transitional flags fail closed: history remains readable, but plugin writes
// are not enabled. Execution still additionally requires the plugin-declared
// feature surface to be available; this flag never authorizes a command by itself.
export function migrationStatus(flags: readonly SCUMFeatureMigrationAuthority[], serverInstanceId: string, feature: SCUMFeatureKey): SCUMFeatureMigrationStatus {
  const matches = flags.filter((flag) => flag.serverInstanceId === serverInstanceId && flag.feature === feature);
  if (matches.length !== 1) return { authority: "transitional-read-only", readOnlyHistory: true, pluginWritesEnabled: false, reason: matches.length ? "迁移标记冲突，已保持只读。" : "当前服务器尚未启用插件权威记录。" };
  const flag = matches[0];
  if (flag.authority !== "plugin") return { authority: "transitional-read-only", readOnlyHistory: true, pluginWritesEnabled: false, reason: flag.reason ?? "过渡记录仅供只读查看。" };
  return { authority: "plugin", readOnlyHistory: true, pluginWritesEnabled: true, reason: flag.reason };
}

export function migratePlayerRecord(record: Record<string, unknown>): SCUMMigrationRecord<SCUMPlayer> | null {
  const id = text(record.id); const gamePlayerId = text(record.gamePlayerId); const displayName = text(record.displayName); if (!id || !gamePlayerId || !displayName) return null;
  const lastSeenAt = timestamp(record.lastSeenAt); const recordedAt = timestamp(record.updatedAt) ?? lastSeenAt ?? new Date(0).toISOString();
  return transitionalReadOnly({ id, gamePlayerId, displayName, ...(lastSeenAt ? { lastSeenAt } : {}), status: record.online === true ? "online" : "unknown" }, recordedAt, id);
}

export function migrateConfigurationRecord(record: Record<string, unknown>): SCUMMigrationRecord<SCUMConfigRead> | null {
  const fields = declaredConfigFields(record.fields); const observedAt = timestamp(record.observedAt) ?? timestamp(record.updatedAt); if (!fields || !observedAt) return null;
  return transitionalReadOnly({ fields, observedAt }, observedAt, text(record.id));
}

export function migratePlayerProfileRecord(record: Record<string, unknown>): SCUMMigrationRecord<SCUMPlayerProfile> | null {
  const player = migratePlayerRecord(object(record.player) ?? record); if (!player) return null;
  const sessions = array(record.sessions).map((item) => migrateSession(item, player.payload.id)).filter((item): item is SCUMPlayerSession => item !== null);
  const risks = [...array(record.accessAttempts), ...array(record.securitySignals)].map(migrateRisk).filter((item): item is SCUMPlayerRisk => item !== null);
  const recordedAt = timestamp(record.updatedAt) ?? player.recordedAt;
  return transitionalReadOnly({ player: player.payload, sessions, risks }, recordedAt, player.sourceRecordId);
}

export function migrateGiftGrantRecord(record: Record<string, unknown>): SCUMMigrationRecord<SCUMGiftGrant> | null {
  const id = text(record.id); const revisionId = text(record.revisionId); const playerId = text(record.gamePlayerRecordId) ?? text(record.playerId); const status = giftStatus(record.status); const createdAt = timestamp(record.createdAt); if (!id || !revisionId || !playerId || !status || !createdAt) return null;
  const completedAt = timestamp(record.completedAt); const notice = optionalText(record.notice) ?? "";
  return transitionalReadOnly({ id, revisionId, playerId, notice, status, createdAt, ...(completedAt ? { completedAt } : {}) }, timestamp(record.updatedAt) ?? createdAt, id);
}

export function migrateStatePatchRecord(record: Record<string, unknown>): SCUMMigrationRecord<SCUMStatePatch> | null {
  const id = text(record.id); const playerId = text(record.gamePlayerRecordId) ?? text(record.playerId); const expectedStateVersion = text(record.expectedStateVersion); const safetyWindow = text(record.safetyWindow); const reason = optionalText(record.reason) ?? ""; const status = stateStatus(record.status); const createdAt = timestamp(record.createdAt); const changes = array(record.changes).map(migrateStateChange).filter((item): item is { fieldKey: string; before: number; after: number } => item !== null);
  if (!id || !playerId || !expectedStateVersion || !safetyWindow || !status || !createdAt || !changes.length) return null;
  return transitionalReadOnly({ id, playerId, expectedStateVersion, safetyWindow, reason, changes, status, createdAt }, timestamp(record.updatedAt) ?? createdAt, id);
}

export function migrateTrajectoryRecord(record: Record<string, unknown>): SCUMTrajectory | null {
  const subjectId = text(record.playerRecordId) ?? text(record.gamePlayerRecordId) ?? text(record.vehicleId) ?? text(record.entityId); const subjectType = trajectorySubjectType(record); const points = Array.isArray(record.points) && subjectId && subjectType ? record.points.map((point) => migratePoint(point, subjectId, subjectType)).filter((point): point is SCUMTrajectoryPoint => point !== null) : [];
  if (!subjectId || !subjectType || !points.length) return null;
  return { subjectId, subjectType, points, provenance: "transitional-read-only" };
}

export function migrateTrajectoryHistoryRecord(record: Record<string, unknown>): SCUMMigrationRecord<SCUMTrajectory> | null {
  const trajectory = migrateTrajectoryRecord(record); if (!trajectory) return null;
  const recordedAt = timestamp(record.updatedAt) ?? trajectory.points[trajectory.points.length - 1].occurredAt;
  return transitionalReadOnly(trajectory, recordedAt, text(record.id));
}

function migratePoint(value: unknown, defaultSubjectId: string, defaultSubjectType: SCUMTrajectoryPoint["subjectType"]): SCUMTrajectoryPoint | null { const record = object(value); if (!record) return null; const x = number(record.mapX) ?? number(record.worldX); const y = number(record.mapY) ?? number(record.worldY); const occurredAt = timestamp(record.recordedAt) ?? timestamp(record.occurredAt); if (x === undefined || y === undefined || !occurredAt) return null; const subjectId = text(record.playerRecordId) ?? text(record.gamePlayerRecordId) ?? text(record.vehicleId) ?? text(record.entityId) ?? defaultSubjectId; const subjectType = trajectorySubjectType(record) ?? defaultSubjectType; return { occurredAt, subjectId, subjectType, x, y, ...(number(record.worldZ) !== undefined ? { z: number(record.worldZ) } : {}), source: "transitional-read-only" }; }
function migrateSession(value: unknown, defaultPlayerId: string): SCUMPlayerSession | null { const record = object(value); const id = record && text(record.id); const playerId = record && (text(record.gamePlayerRecordId) ?? text(record.playerId) ?? defaultPlayerId); const startedAt = record && timestamp(record.startedAt); if (!id || !playerId || !startedAt) return null; const endedAt = timestamp(record.endedAt); return { id, playerId, kind: endedAt ? "logout" : "login", occurredAt: endedAt ?? startedAt }; }
function migrateRisk(value: unknown): SCUMPlayerRisk | null { const record = object(value); const observedAt = record && (timestamp(record.occurredAt) ?? timestamp(record.lastObservedAt)); const kind = record && (text(record.ruleKey) ?? text(record.outcome)); const summary = record && (text(record.summary) ?? text(record.reason)); if (!observedAt || !kind || !summary) return null; return { kind, level: "medium", observedAt, summary }; }
function migrateStateChange(value: unknown): { fieldKey: string; before: number; after: number } | null { const record = object(value); if (!record) return null; const fieldKey = text(record.fieldKey); const before = number(record.before); const after = number(record.after); return fieldKey && before !== undefined && after !== undefined ? { fieldKey, before, after } : null; }
function declaredConfigFields(value: unknown): Record<string, string> | null { const fields = object(value); const allowed = new Set(configurationCatalog.flatMap((field) => [field.configKey, field.configKey.replace(/^scum\./, "")])); if (!fields || !allowed.size) return null; const result: Record<string, string> = {}; for (const [key, field] of Object.entries(fields)) { if (allowed.has(key) && (typeof field === "string" || typeof field === "number" || typeof field === "boolean")) result[key] = String(field); } return Object.keys(result).length ? result : null; }
function giftStatus(value: unknown): SCUMGiftGrant["status"] | null { return value === "pending-approval" || value === "queued" || value === "delivered" || value === "notification_failed" || value === "failed" || value === "unknown" ? value : null; }
function stateStatus(value: unknown): SCUMStatePatch["status"] | null { if (value === "pending-approval" || value === "queued" || value === "unsupported" || value === "unknown" || value === "execution-unknown") return value === "execution-unknown" ? "unknown" : value; if (value === "confirmed") return "succeeded"; return value === "execution-failed" || value === "confirmation-failed" || value === "failed" ? "failed" : null; }
function trajectorySubjectType(record: Record<string, unknown>): SCUMTrajectoryPoint["subjectType"] | null { if (record.kind === "player" || record.kind === "vehicle") return record.kind; return text(record.playerRecordId) || text(record.gamePlayerRecordId) ? "player" : text(record.vehicleId) ? "vehicle" : null; }
function array(value: unknown): unknown[] { return Array.isArray(value) ? value : []; }
function object(value: unknown): Record<string, unknown> | null { return value && typeof value === "object" && !Array.isArray(value) ? value as Record<string, unknown> : null; }
function text(value: unknown): string | undefined { return typeof value === "string" && value.trim() ? value : undefined; }
function optionalText(value: unknown): string | undefined { return text(value); }
function number(value: unknown): number | undefined { return typeof value === "number" && Number.isFinite(value) ? value : undefined; }
function timestamp(value: unknown): string | undefined { const candidate = text(value); return candidate && !Number.isNaN(Date.parse(candidate)) ? candidate : undefined; }