// services/renderers/callReportRenderer.js

import { CALL_BUCKETS } from '../callReport/groupCdrCalls.js';
import { formatCallBlock } from '../callReport/formatCallLine.js';
import { collapseAaBursts } from '../callReport/collapseDisplayCalls.js';
import { callReportEnvInt } from '../callReport/env.js';

function fmtTime(iso) {
  if (!iso) return '—';
  try {
    return new Date(iso).toISOString().replace('T', ' ').replace(/\.\d{3}Z$/, ' UTC');
  } catch {
    return String(iso);
  }
}

function renderOutcomeBreakdown(outcomes) {
  const entries = Object.entries(outcomes || {});
  if (!entries.length) return '_No outcome data._';
  return entries
    .sort((a, b) => b[1] - a[1])
    .map(([k, v]) => `- **${k}:** ${v}`)
    .join('\n');
}

function renderReachSummary(summary) {
  const lines = [];
  if (summary.inbound > 0) {
    lines.push(`- **Inbound reached a phone:** ${summary.inboundReachedPhone} of ${summary.inbound}`);
    if (summary.inboundAaOnly > 0) {
      lines.push(`- **Inbound stopped at auto-attendant:** ${summary.inboundAaOnly}`);
    }
  }
  if (summary.outbound > 0) {
    lines.push(`- **Outbound connected:** ${summary.outboundConnected} of ${summary.outbound}`);
  }
  if (summary.abnormal > 0) {
    lines.push(`- **Abnormal outcomes:** ${summary.abnormal}`);
  }
  return lines.join('\n');
}

function renderCallSection(title, calls, { timeZone, includeWan, maxRows, detail, collapseAa = false }) {
  if (!calls?.length) return '';
  const displayCalls = collapseAa ? collapseAaBursts(calls, { timeZone }) : calls;
  const show = displayCalls.slice(0, maxRows);
  let md = `\n### ${title} (${calls.length})\n`;
  for (const item of show) {
    if (item.kind === 'burst') {
      md += `${item.summary}\n\n`;
      continue;
    }
    const { line1, line2 } = formatCallBlock(item, { timeZone, includeWan, detail });
    md += `${line1}\n`;
    if (line2) md += `${line2}\n`;
    md += '\n';
  }
  if (displayCalls.length > maxRows) {
    md += `_${displayCalls.length - maxRows} more in this section — use Control Hub for full export._\n`;
  }
  return md;
}

function renderReportTitle(target) {
  if (!target) return 'Call report';
  if (target.kind === 'store') return `Call report — Store ${target.storeNum}`;
  return `Call report — ${target.label}`;
}

function renderScopeLine(target) {
  if (!target || target.kind === 'store') return null;
  if (target.kind === 'user') return `- **Scope:** user ${target.email || target.label}`;
  if (target.kind === 'number') return `- **Scope:** number ${target.label}`;
  return null;
}

/**
 * @param {object} report from collectCallReport
 * @param {{ detail?: boolean }} opts
 */
export function renderCallReportMarkdown(report, opts = {}) {
  if (!report?.ok) {
    const target = report?.target || report?.store;
    let md = `**Call report** — ${target?.label || target?.storeNum || '?'}\n\n`;
    md += `_${report?.reason || report?.window?.reason || 'Unable to build report.'}_\n`;
    return md.trim();
  }

  const { store, target: reportTarget, window, cdr, prisma, joined } = report;
  const target = reportTarget || store;
  const summary = joined.summary || {};
  const buckets = joined.buckets || {};
  const maxRows = callReportEnvInt('MAX_DETAIL_ROWS', 25);
  const detail = Boolean(opts.detail);
  const timeZone = window.timeZone;

  let md = `**${renderReportTitle(target)}**\n\n`;
  md += `- **Date:** ${window.label} (${window.mode})\n`;
  md += `- **Timezone:** ${window.timeZone}\n`;
  md += `- **Window:** ${fmtTime(window.startTime)} → ${fmtTime(window.endTime)}\n`;
  md += `- **Location:** ${store.locationName}\n`;
  if (store.dialNumber) md += `- **Main:** ${store.dialNumber}\n`;
  const scopeLine = renderScopeLine(target);
  if (scopeLine) md += `${scopeLine}\n`;

  md += '\n**Call volume (CDR)**\n';
  if (!cdr.available) {
    md += `_CDR unavailable:_ ${cdr.reason || 'unknown'}\n`;
  } else {
    md += `- **Total calls:** ${summary.total ?? 0}\n`;
    md += `- **Inbound:** ${summary.inbound ?? 0} | **Outbound:** ${summary.outbound ?? 0}\n`;
    md += `- **CDR legs fetched:** ${cdr.rawCount ?? '—'} → **${summary.total ?? 0}** correlated call(s)\n`;
    const reach = renderReachSummary(summary);
    if (reach) md += `${reach}\n`;
    if (target?.filter && summary.total === 0) {
      md += '_No calls matched scope in this window._\n';
    }
    md += '\n**Call outcomes**\n';
    md += `${renderOutcomeBreakdown(summary.outcomes)}\n`;
  }

  md += '\n**WAN voice (Prisma DPI)**\n';
  if (!prisma.available) {
    md += `_Unavailable:_ ${prisma.reason || 'not configured'}\n`;
  } else {
    const m = prisma.appAudio?.mos;
    md += `- **App:** ${prisma.appAudio.appName}\n`;
    if (m?.min != null && m?.max != null) {
      md += `- **Worst MOS in window:** ${m.min}  |  **Best MOS:** ${m.max}\n`;
    } else if (m?.min != null) {
      md += `- **Worst MOS in window:** ${m.min}\n`;
    }
    if (prisma.appAudio?.detailsUrl) {
      md += `- [View in Prisma SCM](${prisma.appAudio.detailsUrl})\n`;
    }
  }

  if (cdr.available) {
    const sectionOpts = { timeZone, includeWan: true, maxRows, detail };
    md += renderCallSection(
      'Inbound — reached a phone',
      buckets[CALL_BUCKETS.inboundReachedPhone],
      sectionOpts,
    );
    md += renderCallSection(
      'Inbound — stopped at auto-attendant',
      buckets[CALL_BUCKETS.inboundAaOnly],
      { ...sectionOpts, collapseAa: true },
    );
    md += renderCallSection(
      'Outbound — connected',
      buckets[CALL_BUCKETS.outboundConnected],
      sectionOpts,
    );
    md += renderCallSection(
      'Other / unanswered',
      buckets[CALL_BUCKETS.other],
      sectionOpts,
    );
  }

  md += `\n*Generated in ${report.elapsedMs}ms*`;
  return md.trim();
}