import {
  buildAssistantMcpDiscoveryPlan,
  type AssistantMcpDiscoveryPlanContract,
  type AssistantMcpDiscoveryPrimitive,
  type AssistantMcpDiscoveryTurnMeaningRef
} from "./assistantMcpDiscoveryPolicy";
import {
  reviewAssistantMcpDiscoveryPlanAgainstCatalog,
  type AssistantMcpCatalogPlanReview
} from "./assistantMcpCatalogIndex";

export const ASSISTANT_MCP_DISCOVERY_PLANNER_SCHEMA_VERSION = "assistant_mcp_discovery_planner_v1" as const;

export type AssistantMcpDiscoveryPlannerStatus = "ready_for_execution" | "needs_clarification" | "blocked";

export interface AssistantMcpDiscoveryPlannerInput {
  semanticDataNeed?: string | null;
  turnMeaning?: AssistantMcpDiscoveryTurnMeaningRef | null;
}

export interface AssistantMcpDiscoveryPlannerContract {
  schema_version: typeof ASSISTANT_MCP_DISCOVERY_PLANNER_SCHEMA_VERSION;
  policy_owner: "assistantMcpDiscoveryPlanner";
  planner_status: AssistantMcpDiscoveryPlannerStatus;
  semantic_data_need: string | null;
  proposed_primitives: AssistantMcpDiscoveryPrimitive[];
  required_axes: string[];
  discovery_plan: AssistantMcpDiscoveryPlanContract;
  catalog_review: AssistantMcpCatalogPlanReview;
  reason_codes: string[];
}

interface PlannerRecipe {
  semanticDataNeed: string;
  primitives: AssistantMcpDiscoveryPrimitive[];
  axes: string[];
  reason: string;
}

interface PlannerBudgetOverride {
  maxProbeCount?: number;
}

function toNonEmptyString(value: unknown): string | null {
  if (value === null || value === undefined) {
    return null;
  }
  const text = String(value).trim();
  return text.length > 0 ? text : null;
}

function lower(value: unknown): string {
  return String(value ?? "").trim().toLowerCase();
}

function normalizeReasonCode(value: string): string | null {
  const normalized = value
    .trim()
    .replace(/[^\p{L}\p{N}_.:-]+/gu, "_")
    .replace(/^_+|_+$/g, "")
    .toLowerCase();
  return normalized.length > 0 ? normalized.slice(0, 120) : null;
}

function pushReason(target: string[], value: string): void {
  const normalized = normalizeReasonCode(value);
  if (normalized && !target.includes(normalized)) {
    target.push(normalized);
  }
}

function pushUnique(target: string[], value: string): void {
  const text = value.trim();
  if (text && !target.includes(text)) {
    target.push(text);
  }
}

function hasEntity(meaning: AssistantMcpDiscoveryTurnMeaningRef | null | undefined): boolean {
  return (meaning?.explicit_entity_candidates?.length ?? 0) > 0;
}

function aggregationAxis(meaning: AssistantMcpDiscoveryTurnMeaningRef | null | undefined): string | null {
  return toNonEmptyString(meaning?.asked_aggregation_axis)?.toLowerCase() ?? null;
}

function addScopeAxes(axes: string[], meaning: AssistantMcpDiscoveryTurnMeaningRef | null | undefined): void {
  if (hasEntity(meaning)) {
    pushUnique(axes, "counterparty");
  }
  if (toNonEmptyString(meaning?.explicit_organization_scope)) {
    pushUnique(axes, "organization");
  }
  if (toNonEmptyString(meaning?.explicit_date_scope)) {
    pushUnique(axes, "period");
  }
}

function includesAny(text: string, tokens: string[]): boolean {
  return tokens.some((token) => text.includes(token));
}

function isYearDateScope(meaning: AssistantMcpDiscoveryTurnMeaningRef | null | undefined): boolean {
  return /^\d{4}$/.test(toNonEmptyString(meaning?.explicit_date_scope) ?? "");
}

function budgetOverrideFor(input: AssistantMcpDiscoveryPlannerInput, recipe: PlannerRecipe): PlannerBudgetOverride {
  const meaning = input.turnMeaning ?? null;
  const requestedAggregationAxis = aggregationAxis(meaning);
  const isValueFlowRecipe =
    recipe.semanticDataNeed === "counterparty value-flow evidence" &&
    recipe.primitives.includes("query_movements");
  if (!isValueFlowRecipe) {
    return {};
  }
  if (requestedAggregationAxis === "month" || isYearDateScope(meaning)) {
    return {
      maxProbeCount: 30
    };
  }
  return {};
}

function recipeFor(input: AssistantMcpDiscoveryPlannerInput): PlannerRecipe {
  const meaning = input.turnMeaning ?? null;
  const domain = lower(meaning?.asked_domain_family);
  const action = lower(meaning?.asked_action_family);
  const unsupported = lower(meaning?.unsupported_but_understood_family);
  const combined = `${domain} ${action} ${unsupported}`.trim();
  const axes: string[] = [];
  const requestedAggregationAxis = aggregationAxis(meaning);
  addScopeAxes(axes, meaning);

  if (includesAny(combined, ["turnover", "revenue", "payment", "payout", "value", "net", "netting", "balance", "cashflow"])) {
    pushUnique(axes, "aggregate_axis");
    pushUnique(axes, "amount");
    pushUnique(axes, "coverage_target");
    if (requestedAggregationAxis === "month") {
      pushUnique(axes, "calendar_month");
    }
    return {
      semanticDataNeed: "counterparty value-flow evidence",
      primitives: ["resolve_entity_reference", "query_movements", "aggregate_by_axis", "probe_coverage"],
      axes,
      reason: requestedAggregationAxis === "month"
        ? "planner_selected_monthly_value_flow_recipe"
        : "planner_selected_value_flow_recipe"
    };
  }

  if (includesAny(combined, ["lifecycle", "activity", "duration", "age"])) {
    pushUnique(axes, "document_date");
    pushUnique(axes, "coverage_target");
    pushUnique(axes, "evidence_basis");
    return {
      semanticDataNeed: "counterparty lifecycle evidence",
      primitives: ["resolve_entity_reference", "query_documents", "probe_coverage", "explain_evidence_basis"],
      axes,
      reason: "planner_selected_lifecycle_recipe"
    };
  }

  if (includesAny(combined, ["metadata", "schema", "catalog"])) {
    pushUnique(axes, "metadata_scope");
    return {
      semanticDataNeed: "1C metadata evidence",
      primitives: ["inspect_1c_metadata"],
      axes,
      reason: "planner_selected_metadata_recipe"
    };
  }

  if (includesAny(combined, ["document", "documents"])) {
    pushUnique(axes, "coverage_target");
    return {
      semanticDataNeed: "document evidence",
      primitives: ["resolve_entity_reference", "query_documents", "probe_coverage"],
      axes,
      reason: "planner_selected_document_recipe"
    };
  }

  if (hasEntity(meaning)) {
    pushUnique(axes, "business_entity");
    return {
      semanticDataNeed: "entity discovery evidence",
      primitives: ["search_business_entity", "resolve_entity_reference", "probe_coverage"],
      axes,
      reason: "planner_selected_entity_resolution_recipe"
    };
  }

  return {
    semanticDataNeed: "unclassified 1C discovery need",
    primitives: ["inspect_1c_metadata"],
    axes,
    reason: "planner_selected_clarification_recipe"
  };
}

function statusFrom(
  plan: AssistantMcpDiscoveryPlanContract,
  review: AssistantMcpCatalogPlanReview
): AssistantMcpDiscoveryPlannerStatus {
  if (plan.plan_status === "blocked" || review.review_status === "catalog_blocked") {
    return "blocked";
  }
  if (plan.plan_status !== "allowed" || review.review_status !== "catalog_compatible") {
    return "needs_clarification";
  }
  return "ready_for_execution";
}

export function planAssistantMcpDiscovery(
  input: AssistantMcpDiscoveryPlannerInput
): AssistantMcpDiscoveryPlannerContract {
  const recipe = recipeFor(input);
  const budgetOverride = budgetOverrideFor(input, recipe);
  const semanticDataNeed = toNonEmptyString(input.semanticDataNeed) ?? recipe.semanticDataNeed;
  const reasonCodes: string[] = [];
  pushReason(reasonCodes, recipe.reason);
  if (budgetOverride.maxProbeCount) {
    pushReason(reasonCodes, "planner_enabled_chunked_coverage_probe_budget");
  }

  const plan = buildAssistantMcpDiscoveryPlan({
    semanticDataNeed,
    turnMeaning: input.turnMeaning,
    proposedPrimitives: recipe.primitives,
    requiredAxes: recipe.axes,
    maxProbeCount: budgetOverride.maxProbeCount
  });
  const review = reviewAssistantMcpDiscoveryPlanAgainstCatalog(plan);
  const plannerStatus = statusFrom(plan, review);

  if (plannerStatus === "ready_for_execution") {
    pushReason(reasonCodes, "planner_ready_for_guarded_mcp_execution");
  } else if (plannerStatus === "blocked") {
    pushReason(reasonCodes, "planner_blocked_by_policy_or_catalog");
  } else {
    pushReason(reasonCodes, "planner_needs_more_user_or_scope_context");
  }

  return {
    schema_version: ASSISTANT_MCP_DISCOVERY_PLANNER_SCHEMA_VERSION,
    policy_owner: "assistantMcpDiscoveryPlanner",
    planner_status: plannerStatus,
    semantic_data_need: semanticDataNeed,
    proposed_primitives: recipe.primitives,
    required_axes: recipe.axes,
    discovery_plan: plan,
    catalog_review: review,
    reason_codes: reasonCodes
  };
}