import type { AgentExecutionReceipt, ConsultationAgentPublicEvent } from "./consultation-agent-events.ts";
import {
  CONSULTATION_CHART_CALCULATION_LABEL,
  CONSULTATION_COMPOSING_LABEL,
  CONSULTATION_DONE_CHART_LABEL,
  CONSULTATION_DONE_SKILL_LABEL,
  CONSULTATION_LOADING_METHOD_LABEL,
  consultationWriteLabel,
} from "./consultation-activity-labels.ts";
import {
  consultationDomainDefinition,
  normalizeConsultationDomain,
} from "./consultation-domain-registry.ts";
import type { PublicThinkingSection } from "./consultation-thinking-plan.ts";

export const CONSULTATION_TIMELINE_KINDS = ["method", "calculate", "think", "write"] as const;
export type ConsultationTimelineKind = (typeof CONSULTATION_TIMELINE_KINDS)[number];
export type ConsultationTimelineStatus = "live" | "done";

export type ConsultationTimelineRow = Readonly<{
  id: string;
  kind: ConsultationTimelineKind;
  status: ConsultationTimelineStatus;
  label: string;
  queries?: readonly string[];
  sources?: readonly string[];
  thinkingText?: string;
}>;

export type ConsultationTimelineState = Readonly<{
  rows: readonly ConsultationTimelineRow[];
  answer: string;
}>;

const METHOD_ID = "method";
const CALCULATE_ID = "calculate";

export function emptyConsultationTimeline(): ConsultationTimelineState {
  return { rows: [], answer: "" };
}

export function reduceConsultationTimeline(
  state: ConsultationTimelineState,
  event: ConsultationAgentPublicEvent,
): ConsultationTimelineState {
  if (event.type === "skill.started") {
    return upsertRow(state, {
      id: METHOD_ID,
      kind: "method",
      status: "live",
      label: CONSULTATION_LOADING_METHOD_LABEL,
    });
  }
  if (event.type === "skill.completed") {
    return completeRow(state, METHOD_ID, CONSULTATION_DONE_SKILL_LABEL);
  }
  if (event.type === "tool.started") {
    return upsertRow(completeLiveThink(state), {
      id: CALCULATE_ID,
      kind: "calculate",
      status: "live",
      label: event.label || CONSULTATION_CHART_CALCULATION_LABEL,
    });
  }
  if (event.type === "activity") {
    if (event.phase === "chart-calculation") {
      return patchRow(state, CALCULATE_ID, {
        status: "live",
        label: event.label,
      }, {
        id: CALCULATE_ID,
        kind: "calculate",
        status: "live",
        label: event.label,
      });
    }
    if (event.phase === "evidence-validation") {
      return completeRow(state, CALCULATE_ID, CONSULTATION_DONE_CHART_LABEL);
    }
    if (event.phase === "answer-composition") {
      return upsertWrite(completeLiveThink(state), event.label);
    }
    return state;
  }
  if (event.type === "tool.completed") {
    return completeRow(state, CALCULATE_ID, CONSULTATION_DONE_CHART_LABEL);
  }
  if (event.type === "tool.failed") {
    return completeRow(state, CALCULATE_ID, CONSULTATION_DONE_CHART_LABEL);
  }
  if (event.type === "thinking.section") {
    const section: PublicThinkingSection = {
      id: event.id,
      title: event.title,
      heading: event.heading,
      steps: event.steps,
    };
    const withCalc = enrichCalculate(completeRow(state, CALCULATE_ID, CONSULTATION_DONE_CHART_LABEL), section);
    const withoutOpen = completeLiveThink(withCalc);
    return upsertRow(withoutOpen, {
      id: `think-${section.id}`,
      kind: "think",
      status: "live",
      label: consultationThinkTitle(section.title),
    });
  }
  if (event.type === "thinking.delta") {
    const think = lastRow(state.rows, (row) => row.kind === "think" && row.status === "live");
    if (think) {
      const thinkingText = `${think.thinkingText ?? ""}${event.text}`.slice(0, 4_000);
      return upsertRow(state, { ...think, status: "live", thinkingText });
    }
    const thinkCount = state.rows.filter((row) => row.kind === "think").length;
    return upsertRow(state, {
      id: `think-open-${thinkCount + 1}`,
      kind: "think",
      status: "live",
      label: "正在分析…",
      thinkingText: event.text.slice(0, 4_000),
    });
  }
  if (event.type === "answer.delta") {
    const next = { ...completeLiveThink(state), answer: `${state.answer}${event.text}` };
    return syncWriteRows(next, false);
  }
  if (event.type === "run.completed" || event.type === "run.failed") {
    const next = syncWriteRows(completeLiveThink(state), true);
    return {
      ...next,
      rows: next.rows.map((row) => (
        row.status === "done" ? row : { ...row, status: "done" as const, label: doneLabel(row) }
      )),
    };
  }
  return state;
}

export function reduceConsultationTimelineEvents(
  events: readonly ConsultationAgentPublicEvent[],
  state = emptyConsultationTimeline(),
): ConsultationTimelineState {
  return events.reduce(reduceConsultationTimeline, state);
}

export function consultationTimelineFromSettled(input: {
  text?: string;
  thinkingText?: string;
  thinkingSections?: readonly PublicThinkingSection[];
  agentExecutionReceipt?: AgentExecutionReceipt;
}): readonly ConsultationTimelineRow[] {
  const text = input.text?.trim() ?? "";
  const sections = input.thinkingSections ?? [];
  const receipt = input.agentExecutionReceipt;
  if (!text && !sections.length && !input.thinkingText?.trim() && !receipt) return [];

  const events: ConsultationAgentPublicEvent[] = [
    { type: "skill.started", name: "jyotish-vedic-astrology" },
    { type: "skill.completed", name: "jyotish-vedic-astrology" },
  ];
  const calculated = receipt?.steps.some((step) => step.kind === "tool")
    || sections.some((section) => section.id.startsWith("domain-"));
  if (calculated) {
    events.push({
      type: "tool.started",
      callId: "settled",
      tool: "run-jyotish-consultation",
      label: CONSULTATION_CHART_CALCULATION_LABEL,
    });
    events.push({
      type: "tool.completed",
      callId: "settled",
      tool: "run-jyotish-consultation",
      status: "ready",
      durationMs: 0,
    });
  }
  for (const section of sections) {
    events.push({ type: "thinking.section", ...section });
  }
  if (input.thinkingText?.trim() && sections.length === 0) {
    events.push({ type: "thinking.delta", text: input.thinkingText });
  }
  if (text) events.push({ type: "answer.delta", text });
  events.push({
    type: "run.completed",
    receipt: receipt ?? {
      runId: "settled",
      runtime: "mastra-agentic",
      skill: {
        name: "jyotish-vedic-astrology",
        loaded: true,
        referenceReads: 0,
        methodologySections: 0,
      },
      steps: [],
      workflow: { route: "settled", status: "ready", preciseTiming: "blocked", missingLayers: [] },
    },
  });
  let state = reduceConsultationTimelineEvents(events);
  if (input.thinkingText?.trim() && sections.length > 0) {
    const lastThink = [...state.rows].reverse().find((row) => row.kind === "think");
    if (lastThink) {
      state = upsertRow(state, { ...lastThink, thinkingText: input.thinkingText.slice(0, 4_000) });
    }
  }
  return state.rows;
}

export function consultationThinkTitle(title: string): string {
  const cleaned = title.replace(/\s+/g, " ").trim();
  if (cleaned.length <= 20) return cleaned || "正在分析";
  return cleaned.slice(0, 20);
}

function answerHeadings(text: string): string[] {
  return [...text.matchAll(/^##\s+(.+?)\s*$/gm)].map((match) => match[1]?.trim() ?? "").filter(Boolean);
}

function queriesFromSection(section: PublicThinkingSection): string[] {
  const domain = section.id.startsWith("domain-")
    ? normalizeConsultationDomain(section.id.slice("domain-".length))
    : null;
  if (!domain) return [];
  const definition = consultationDomainDefinition(domain);
  return uniqueLabels([definition.label, ...definition.evidencePreview]).slice(0, 8);
}

function sourcesFromSection(section: PublicThinkingSection): string[] {
  return uniqueLabels(section.steps
    .map((step) => step.label.replace(/^对照\s+/, "").trim())
    .filter((label) => label.length > 0 && label.length <= 24)).slice(0, 8);
}

function uniqueLabels(values: readonly string[]): string[] {
  const seen = new Set<string>();
  const kept: string[] = [];
  for (const value of values) {
    const label = value.replace(/\s+/g, " ").trim();
    if (!label || seen.has(label)) continue;
    seen.add(label);
    kept.push(label);
  }
  return kept;
}

function lastRow(
  rows: readonly ConsultationTimelineRow[],
  match: (row: ConsultationTimelineRow) => boolean,
): ConsultationTimelineRow | undefined {
  for (let index = rows.length - 1; index >= 0; index -= 1) {
    const row = rows[index];
    if (row && match(row)) return row;
  }
  return undefined;
}

function upsertRow(state: ConsultationTimelineState, row: ConsultationTimelineRow): ConsultationTimelineState {
  const index = state.rows.findIndex((item) => item.id === row.id);
  if (index < 0) return { ...state, rows: [...state.rows, row] };
  return {
    ...state,
    rows: state.rows.map((item, current) => (current === index ? { ...item, ...row } : item)),
  };
}

function patchRow(
  state: ConsultationTimelineState,
  id: string,
  patch: Partial<ConsultationTimelineRow>,
  create?: ConsultationTimelineRow,
): ConsultationTimelineState {
  const existing = state.rows.find((row) => row.id === id);
  if (!existing) return create ? upsertRow(state, create) : state;
  return upsertRow(state, { ...existing, ...patch, id, kind: existing.kind });
}

function completeRow(
  state: ConsultationTimelineState,
  id: string,
  label?: string,
): ConsultationTimelineState {
  const existing = state.rows.find((row) => row.id === id);
  if (!existing) return state;
  return upsertRow(state, {
    ...existing,
    status: "done",
    label: label ?? doneLabel(existing),
  });
}

function completeLiveThink(state: ConsultationTimelineState): ConsultationTimelineState {
  return {
    ...state,
    rows: state.rows.map((row) => (
      row.kind === "think" && row.status === "live"
        ? { ...row, status: "done" as const, label: doneLabel(row) }
        : row
    )),
  };
}

function doneLabel(row: ConsultationTimelineRow): string {
  if (row.kind === "method") return CONSULTATION_DONE_SKILL_LABEL;
  if (row.kind === "calculate") return CONSULTATION_DONE_CHART_LABEL;
  if (row.kind === "write") {
    const heading = row.id.startsWith("write-") ? row.id.slice("write-".length) : "";
    return heading ? consultationWriteLabel(heading, false) : row.label.replace(/…$/, "").replace(/^正在/, "");
  }
  return row.label.replace(/…$/, "").replace(/^正在/, "") || row.label;
}

function upsertWrite(state: ConsultationTimelineState, liveLabel: string): ConsultationTimelineState {
  const headings = answerHeadings(state.answer);
  const heading = headings.at(-1);
  if (!heading) {
    return upsertRow(state, {
      id: "write-open",
      kind: "write",
      status: "live",
      label: liveLabel || CONSULTATION_COMPOSING_LABEL,
    });
  }
  return syncWriteRows(state, false);
}

function syncWriteRows(state: ConsultationTimelineState, settled: boolean): ConsultationTimelineState {
  const headings = answerHeadings(state.answer);
  if (headings.length === 0) {
    if (!state.answer.trim() && !settled) return state;
    if (!state.answer.trim()) return state;
    return upsertRow(completeRow(state, "write-open"), {
      id: "write-open",
      kind: "write",
      status: settled ? "done" : "live",
      label: settled ? "组织回答" : CONSULTATION_COMPOSING_LABEL,
    });
  }
  let next = completeRow(state, "write-open");
  next = {
    ...next,
    rows: next.rows.filter((row) => row.id !== "write-open"),
  };
  headings.forEach((heading, index) => {
    const last = index === headings.length - 1;
    next = upsertRow(next, {
      id: `write-${heading}`,
      kind: "write",
      status: settled || !last ? "done" : "live",
      label: consultationWriteLabel(heading, !settled && last),
    });
  });
  return next;
}

function enrichCalculate(
  state: ConsultationTimelineState,
  section: PublicThinkingSection,
): ConsultationTimelineState {
  const calculate = state.rows.find((row) => row.id === CALCULATE_ID);
  if (!calculate) return state;
  const queries = uniqueLabels([...(calculate.queries ?? []), ...queriesFromSection(section)]).slice(0, 8);
  const sources = uniqueLabels([...(calculate.sources ?? []), ...sourcesFromSection(section)]).slice(0, 8);
  return upsertRow(state, { ...calculate, queries, sources });
}