// SPEC: PJ2026-01060703 CI/CD branch follower timing helpers.
// Responsibility: compact branch-follower total/stage timing contracts and performance summaries.
import { prioritizedTaskRunItems } from "./cicd-taskruns";
import type { AdapterSummary, BranchFollowerPhase, FollowerSpec, FollowerState, StageTiming } from "./cicd-types";

type TotalTiming = {
  seconds: number;
  status: string;
  source: string;
  sourceCommit: string | null;
  startedAt: string | null;
  finishedAt: string | null;
};

export function buildFollowerTimings(
  follower: FollowerSpec,
  live: AdapterSummary,
  triggerCommand: Record<string, unknown> | undefined,
  storedTimings?: Record<string, unknown> | null,
  phase?: BranchFollowerPhase,
): FollowerState["timings"] {
  const nativePayload = asOptionalRecord(live.payload);
  const finishOverride = stringOrNull(triggerCommand?.finishedAt) ?? noopStoredTotalFinishOverride(storedTimings, phase, live);
  const total = totalTimingFromCommand(triggerCommand, phase) ?? totalTimingFromStored(storedTimings, phase, finishOverride, live.observedSha);
  const storedStages = live.observedSha !== null && stringOrNull(storedTimings?.sourceCommit) === live.observedSha ? storedStageTimings(storedTimings ?? null) : [];
  const stages = dedupeTimingStages([
    ...stageTimingsFromCommand(triggerCommand),
    ...stageTimingsFromNativePayload(nativePayload, total),
    ...storedStages,
  ]).slice(0, 24);
  const stageSourceCommit = stages.length > 0 ? live.observedSha : null;
  return {
    budgetSeconds: follower.budgets.endToEndSeconds,
    totalSeconds: total?.seconds ?? null,
    totalStatus: total?.status ?? "unknown",
    totalSource: total?.source ?? "-",
    sourceCommit: total?.sourceCommit ?? stringOrNull(triggerCommand?.sourceCommit) ?? stageSourceCommit,
    startedAt: total?.startedAt ?? null,
    finishedAt: total?.finishedAt ?? null,
    overBudget: total === null ? null : total.seconds > follower.budgets.endToEndSeconds,
    stages,
  };
}

export function storedFollowerTimingsForStatus(
  follower: FollowerSpec,
  storedTimings: Record<string, unknown> | null,
  phase: BranchFollowerPhase,
  observedSha: string | null,
): FollowerState["timings"] {
  const total = totalTimingFromStored(storedTimings, phase, null, observedSha);
  const sourceCommit = total?.sourceCommit ?? stringOrNull(storedTimings?.sourceCommit) ?? null;
  return {
    budgetSeconds: follower.budgets.endToEndSeconds,
    totalSeconds: total?.seconds ?? null,
    totalStatus: total?.status ?? "unknown",
    totalSource: total?.source ?? "-",
    sourceCommit,
    startedAt: total?.startedAt ?? null,
    finishedAt: total?.finishedAt ?? null,
    overBudget: total === null ? null : total.seconds > follower.budgets.endToEndSeconds,
    stages: sourceCommit === null ? [] : storedStageTimings(storedTimings),
  };
}

export function compactTimings(timings: FollowerState["timings"]): FollowerState["timings"] {
  return {
    budgetSeconds: timings.budgetSeconds,
    totalSeconds: timings.totalSeconds,
    totalStatus: timings.totalStatus,
    totalSource: timings.totalSource,
    sourceCommit: timings.sourceCommit,
    startedAt: timings.startedAt,
    finishedAt: timings.finishedAt,
    overBudget: timings.overBudget,
    stages: timings.stages.slice(0, 24).map((stage) => ({
      stage: stage.stage,
      status: stage.status,
      seconds: stage.seconds,
      budgetSeconds: stage.budgetSeconds,
      source: stage.source,
      object: stage.object,
    })),
  };
}

export function compactListTimings(timings: FollowerState["timings"]): Record<string, unknown> {
  return {
    budgetSeconds: timings.budgetSeconds,
    totalSeconds: timings.totalSeconds,
    totalStatus: timings.totalStatus,
    totalSource: timings.totalSource,
    sourceCommit: timings.sourceCommit,
    startedAt: timings.startedAt,
    finishedAt: timings.finishedAt,
    overBudget: timings.overBudget,
    stages: timings.stages.slice(0, 4).map((stage) => ({
      stage: stage.stage,
      status: stage.status,
      seconds: stage.seconds,
    })),
  };
}

export function timingPerformanceSummary(timings: FollowerState["timings"]): Record<string, unknown> {
  const slowStages = timings.stages
    .filter((stage) => stage.seconds !== null)
    .sort((a, b) => (b.seconds ?? 0) - (a.seconds ?? 0))
    .slice(0, 5)
    .map((stage) => ({
      stage: stage.stage,
      status: stage.status,
      seconds: stage.seconds,
      source: stage.source,
      object: stage.object,
    }));
  return {
    budgetSeconds: timings.budgetSeconds,
    totalSeconds: timings.totalSeconds,
    totalSource: timings.totalSource,
    sourceCommit: timings.sourceCommit,
    startedAt: timings.startedAt,
    finishedAt: timings.finishedAt,
    overBudget: timings.overBudget,
    slowestStage: slowStages[0] ?? null,
    slowStages,
    note: timings.overBudget === true ? "advisory budget exceeded; inspect slowStages and stage source before rerun" : null,
  };
}

function noopStoredTotalFinishOverride(
  storedTimings: Record<string, unknown> | null | undefined,
  phase: BranchFollowerPhase | undefined,
  live: AdapterSummary,
): string | null {
  if (phase !== "Noop" || live.aligned !== true || live.observedSha === null) return null;
  if (storedTimings === null || storedTimings === undefined) return null;
  if (stringOrNull(storedTimings.sourceCommit) !== live.observedSha) return null;
  if (stringOrNull(storedTimings.startedAt) === null) return null;
  if (stringOrNull(storedTimings.finishedAt) !== null) return null;
  return new Date().toISOString();
}

function storedStageTimings(storedTimings: Record<string, unknown> | null): StageTiming[] {
  if (storedTimings === null) return [];
  return arrayRecords(storedTimings.stages)
    .map((stage) => stageTiming(
      stringOrNull(stage.stage) ?? "",
      stringOrNull(stage.status) ?? "unknown",
      numberOrNull(stage.seconds),
      numberOrNull(stage.budgetSeconds),
      stringOrNull(stage.source) ?? "stored-state",
      stringOrNull(stage.object),
    ))
    .filter((stage) => stage.stage.length > 0)
    .slice(0, 24);
}

function totalTimingFromCommand(command: Record<string, unknown> | undefined, phase?: BranchFollowerPhase): TotalTiming | null {
  if (command === undefined) return null;
  if (command.mode === "k8s-native-closeout") return null;
  const payload = asOptionalRecord(command.payload);
  if (payload?.reused === true) return null;
  const startedAt = stringOrNull(command.startedAt);
  const finishedAt = stringOrNull(command.finishedAt);
  const seconds = totalSecondsFromRange(startedAt, finishedAt) ?? secondsFromMs(numberOrNull(command.elapsedMs));
  if (seconds === null) return null;
  const closeout = asOptionalRecord(command.closeout);
  const exitCode = numberOrNull(command.exitCode);
  const status = command.ok === false || (exitCode !== null && exitCode !== 0)
    ? "failed"
    : command.budgetTimedOut === true || closeout?.timedOut === true
      ? "over-budget"
      : command.timedOut === true
        ? "timed-out"
        : closeout?.completed === true || command.completed === true
          ? "completed"
          : command.stillRunning === true
            ? "running"
            : command.pipelineRunCompleted === true
              ? "ci-completed"
              : phase === undefined
                ? "submitted"
                : phase.toLowerCase();
  return { seconds, status, source: stringOrNull(command.mode) ?? stringOrNull(command.status) ?? "command", sourceCommit: stringOrNull(command.sourceCommit), startedAt, finishedAt };
}

function totalTimingFromStored(storedTimings: Record<string, unknown> | null | undefined, phase?: BranchFollowerPhase, finishOverride?: string | null, observedSha?: string | null): TotalTiming | null {
  if (storedTimings === null || storedTimings === undefined) return null;
  const status = stringOrNull(storedTimings.totalStatus);
  const source = stringOrNull(storedTimings.totalSource);
  const sourceCommit = stringOrNull(storedTimings.sourceCommit);
  if (sourceCommit === null) return null;
  if (observedSha !== null && observedSha !== undefined && sourceCommit !== observedSha) return null;
  const startedAt = stringOrNull(storedTimings.startedAt);
  const finishedAt = stringOrNull(storedTimings.finishedAt) ?? finishOverride ?? null;
  if (phase === "Noop" && finishedAt === null) return null;
  const seconds = totalSecondsFromRange(startedAt, finishedAt) ?? numberOrNull(storedTimings.totalSeconds);
  if (seconds === null) return null;
  return {
    seconds,
    status: finishedAt === null && phase !== undefined && !terminalPhase(phase) ? phase.toLowerCase() : phase === undefined ? status ?? "recorded" : phase.toLowerCase(),
    source: source ?? "stored-state",
    sourceCommit,
    startedAt,
    finishedAt,
  };
}

function totalSecondsFromRange(startedAt: string | null, finishedAt: string | null): number | null {
  const startedMs = timestampMs(startedAt);
  if (startedMs === null) return null;
  const finishedMs = timestampMs(finishedAt) ?? Date.now();
  return finishedMs >= startedMs ? roundSeconds((finishedMs - startedMs) / 1000) : null;
}

function terminalPhase(phase: BranchFollowerPhase): boolean {
  return phase === "Succeeded" || phase === "Failed" || phase === "Blocked" || phase === "Skipped" || phase === "Noop";
}

function stageTimingsFromNativePayload(payload: Record<string, unknown> | null, total: TotalTiming | null): StageTiming[] {
  if (payload === null) return [];
  const stages: StageTiming[] = [];
  const statusRead = asOptionalRecord(asOptionalRecord(payload.timings)?.statusRead);
  stages.push(stageTiming("status-read", "ok", secondsFromMs(numberOrNull(statusRead?.elapsedMs)), numberOrNull(statusRead?.budgetSeconds), "native-status", null));
  const sourceSyncStage = k8sJobTiming("git-mirror-sync", asOptionalRecord(payload.sourceSync));
  if (sourceSyncStage !== null) stages.push(sourceSyncStage);
  const reuseConfig = asOptionalRecord(payload.reuseConfig);
  if (reuseConfig !== null) stages.push(stageTiming("reuse-config", reuseConfig.ok === true ? "ready" : "missing-or-invalid", null, null, "source-gitops", stringOrNull(reuseConfig.path)));
  const gitMirror = asOptionalRecord(payload.gitMirror);
  if (gitMirror !== null) {
    const hasGitopsBranch = stringOrNull(gitMirror.gitopsBranch) !== null;
    const sourceReady = gitMirror.sourceSnapshotReady === true;
    const status = gitMirror.pendingFlush === true ? "pending-flush" : hasGitopsBranch ? gitMirror.githubInSync === true && sourceReady ? "ready" : "not-ready" : sourceReady ? "source-ready" : "source-not-ready";
    stages.push(stageTiming("git-mirror", status, null, null, "git-mirror-cache", stringOrNull(gitMirror.gitopsBranch) ?? stringOrNull(gitMirror.sourceBranch)));
  }
  const tekton = asOptionalRecord(payload.tekton);
  if (tekton !== null) {
    const status = tekton.succeeded === true ? "succeeded" : tekton.succeeded === false ? `failed:${stringOrNull(tekton.reason) ?? "unknown"}` : "running";
    stages.push(stageTiming("pipelinerun", status, numberOrNull(tekton.durationSeconds), null, "tekton", stringOrNull(tekton.name)));
  }
  const taskRuns = asOptionalRecord(payload.taskRuns);
  for (const record of taskRuns === null ? [] : prioritizedTaskRunItems(taskRuns)) {
    const name = stringOrNull(record.pipelineTask) ?? stringOrNull(record.name) ?? "unknown";
    const status = record.status === "True" ? "succeeded" : record.status === "False" ? `failed:${stringOrNull(record.reason) ?? "unknown"}` : "running";
    stages.push(stageTiming(`task:${name}`, status, numberOrNull(record.durationSeconds), null, "tekton-taskrun", stringOrNull(record.name)));
  }
  const argo = asOptionalRecord(payload.argo);
  if (argo !== null) {
    const sameWindow = total === null || timingOverlapsTotal(total, stringOrNull(argo.operationStartedAt), stringOrNull(argo.operationFinishedAt));
    stages.push(stageTiming("argo", `${sameWindow ? "" : "current:"}${stringOrNull(argo.syncStatus) ?? "unknown"}/${stringOrNull(argo.healthStatus) ?? "unknown"}`, sameWindow ? numberOrNull(argo.operationDurationSeconds) : null, null, sameWindow ? "argocd" : "argocd-current", stringOrNull(argo.name)));
  }
  const runtime = asOptionalRecord(payload.runtime);
  if (runtime !== null) {
    const aligned = runtime.aligned === true ? "aligned" : runtime.aligned === false ? "stale" : "unknown-target";
    stages.push(stageTiming("runtime", `${runtime.ready === true ? "ready" : "not-ready"}/${aligned}`, null, null, "kubernetes-workload", stringOrNull(runtime.namespace)));
  }
  return stages;
}

function timingOverlapsTotal(total: TotalTiming, startedAt: string | null, finishedAt: string | null): boolean {
  const totalStart = timestampMs(total.startedAt);
  const totalFinish = timestampMs(total.finishedAt);
  const stageStart = timestampMs(startedAt);
  const stageFinish = timestampMs(finishedAt);
  if (totalStart === null || totalFinish === null || stageStart === null || stageFinish === null) return true;
  const slackMs = 30_000;
  return stageStart <= totalFinish + slackMs && stageFinish >= totalStart - slackMs;
}

function stageTimingsFromCommand(command: Record<string, unknown> | undefined): StageTiming[] {
  if (command === undefined) return [];
  const stages: StageTiming[] = [];
  const phase = stringOrNull(command.phase);
  const jobStage = phase === null ? null : k8sJobTiming(phase, asOptionalRecord(command.job), stringOrNull(command.jobName));
  if (jobStage !== null) stages.push(jobStage);
  const payload = asOptionalRecord(command.payload);
  if (payload !== null) {
    const capabilities = asOptionalRecord(payload.nativeCapabilities);
    for (const stage of [
      k8sJobTiming("git-mirror-sync", asOptionalRecord(capabilities?.gitMirrorSync)),
      k8sJobTiming("control-plane-refresh", asOptionalRecord(capabilities?.controlPlaneRefresh)),
      k8sJobTiming("git-mirror-flush", asOptionalRecord(capabilities?.gitMirrorFlush)),
    ]) if (stage !== null) stages.push(stage);
    const agentrun = asOptionalRecord(payload.agentrun);
    const agentrunSync = asOptionalRecord(agentrun?.gitMirrorSync);
    const agentrunFlush = asOptionalRecord(agentrun?.gitMirrorFlush);
    const imageBuild = asOptionalRecord(agentrun?.imageBuild);
    const gitopsPublish = asOptionalRecord(agentrun?.gitopsPublish);
    for (const stage of [
      k8sJobTiming("git-mirror-sync", asOptionalRecord(agentrunSync?.payload), stringOrNull(agentrunSync?.jobName)),
      k8sJobTiming("image-build", asOptionalRecord(imageBuild?.result), stringOrNull(imageBuild?.jobName)),
      k8sJobTiming("gitops-publish", asOptionalRecord(gitopsPublish?.result), stringOrNull(gitopsPublish?.jobName)),
      k8sJobTiming("git-mirror-flush", asOptionalRecord(agentrunFlush?.payload), stringOrNull(agentrunFlush?.jobName)),
    ]) if (stage !== null) stages.push(stage);
    const tektonSeconds = secondsFromMs(numberOrNull(payload.elapsedMs));
    if (tektonSeconds !== null) {
      const status = payload.completed === true ? "completed" : payload.failed === true ? "failed" : payload.stillRunning === true ? "running" : "submitted";
      stages.push(stageTiming("pipelinerun-wait", status, tektonSeconds, null, "tekton-submit", stringOrNull(command.pipelineRun)));
    }
  }
  const closeout = asOptionalRecord(command.closeout);
  if (closeout !== null) {
    const gitMirrorFlush = asOptionalRecord(closeout.gitMirrorFlush);
    const gitMirrorFlushStage = k8sJobTiming("git-mirror-flush", asOptionalRecord(gitMirrorFlush?.result), stringOrNull(gitMirrorFlush?.jobName));
    if (gitMirrorFlushStage !== null) stages.push(gitMirrorFlushStage);
    const status = closeout.completed === true ? "completed" : closeout.timedOut === true ? "over-budget" : "pending";
    stages.push(stageTiming("closeout", status, secondsFromMs(numberOrNull(closeout.elapsedMs)), null, "k8s-native-closeout", stringOrNull(command.pipelineRun)));
  }
  return stages;
}

function k8sJobTiming(stage: string, job: Record<string, unknown> | null, objectOverride?: string | null): StageTiming | null {
  if (job === null) return null;
  const status = job.completed === true ? job.reused === true ? "reused" : "completed" : job.failed === true ? "failed" : job.timedOut === true ? "over-budget" : "running";
  return stageTiming(stage, status, secondsFromMs(numberOrNull(job.elapsedMs)), null, "kubernetes-job", objectOverride ?? stringOrNull(job.jobName));
}

function stageTiming(stage: string, status: string, seconds: number | null, budgetSeconds: number | null, source: string, object: string | null): StageTiming {
  return { stage, status, seconds, budgetSeconds, source, object };
}

function dedupeTimingStages(stages: StageTiming[]): StageTiming[] {
  const byKey = new Map<string, StageTiming>();
  for (const stage of stages) {
    if (stage.stage.length === 0) continue;
    const key = `${stage.stage}\t${stage.object ?? ""}`;
    const previous = byKey.get(key);
    if (previous === undefined || previous.seconds === null && stage.seconds !== null) byKey.set(key, stage);
  }
  return [...byKey.values()];
}

function secondsFromMs(value: number | null): number | null {
  return value === null ? null : roundSeconds(value / 1000);
}

function roundSeconds(value: number): number {
  return Math.round(value * 10) / 10;
}

function timestampMs(value: string | null): number | null {
  if (value === null) return null;
  const parsed = Date.parse(value);
  return Number.isFinite(parsed) ? parsed : null;
}

function asOptionalRecord(value: unknown): Record<string, unknown> | null {
  return typeof value === "object" && value !== null && !Array.isArray(value) ? value as Record<string, unknown> : null;
}

function arrayRecords(value: unknown): Record<string, unknown>[] {
  return Array.isArray(value) ? value.filter((item): item is Record<string, unknown> => typeof item === "object" && item !== null && !Array.isArray(item)) : [];
}

function stringOrNull(value: unknown): string | null {
  return typeof value === "string" && value.length > 0 ? value : null;
}

function numberOrNull(value: unknown): number | null {
  return typeof value === "number" && Number.isFinite(value) ? value : null;
}