import * as p from "@clack/prompts";
import pc from "picocolors";
import type { PaperclipConfig } from "../config/schema.js";
import { configExists, readConfig, resolveConfigPath } from "../config/store.js";
import {
  readAgentJwtSecretFromEnv,
  readAgentJwtSecretFromEnvFile,
  resolveAgentJwtEnvFile,
} from "../config/env.js";

type EnvSource = "env" | "config" | "file" | "default" | "missing";

type EnvVarRow = {
  key: string;
  value: string;
  source: EnvSource;
  required: boolean;
  note: string;
};

const DEFAULT_AGENT_JWT_TTL_SECONDS = "172800";
const DEFAULT_AGENT_JWT_ISSUER = "paperclip";
const DEFAULT_AGENT_JWT_AUDIENCE = "paperclip-api";
const DEFAULT_HEARTBEAT_SCHEDULER_INTERVAL_MS = "30000";

export async function envCommand(opts: { config?: string }): Promise<void> {
  p.intro(pc.bgCyan(pc.black(" paperclip env ")));

  const configPath = resolveConfigPath(opts.config);
  let config: PaperclipConfig | null = null;
  let configReadError: string | null = null;

  if (configExists(opts.config)) {
    p.log.message(pc.dim(`Config file: ${configPath}`));
    try {
      config = readConfig(opts.config);
    } catch (err) {
      configReadError = err instanceof Error ? err.message : String(err);
      p.log.message(pc.yellow(`Could not parse config: ${configReadError}`));
    }
  } else {
    p.log.message(pc.dim(`Config file missing: ${configPath}`));
  }

  const rows = collectDeploymentEnvRows(config, configPath);
  const missingRequired = rows.filter((row) => row.required && row.source === "missing");
  const sortedRows = rows.sort((a, b) => Number(b.required) - Number(a.required) || a.key.localeCompare(b.key));

  const requiredRows = sortedRows.filter((row) => row.required);
  const optionalRows = sortedRows.filter((row) => !row.required);

  const formatSection = (title: string, entries: EnvVarRow[]) => {
    if (entries.length === 0) return;

    p.log.message(pc.bold(title));
    for (const entry of entries) {
      const status = entry.source === "missing" ? pc.red("missing") : entry.source === "default" ? pc.yellow("default") : pc.green("set");
      const sourceNote = {
        env: "environment",
        config: "config",
        file: "file",
        default: "default",
        missing: "missing",
      }[entry.source];
      p.log.message(
        `${pc.cyan(entry.key)} ${status.padEnd(7)} ${pc.dim(`[${sourceNote}] ${entry.note}`)}${entry.source === "missing" ? "" : ` ${pc.dim("=>")} ${pc.white(quoteShellValue(entry.value))}`}`,
      );
    }
  };

  formatSection("Required environment variables", requiredRows);
  formatSection("Optional environment variables", optionalRows);

  const exportRows = rows.map((row) => (row.source === "missing" ? { ...row, value: "<set-this-value>" } : row));
  const uniqueRows = uniqueByKey(exportRows);
  const exportBlock = uniqueRows.map((row) => `export ${row.key}=${quoteShellValue(row.value)}`).join("\n");

  if (configReadError) {
    p.log.error(`Could not load config cleanly: ${configReadError}`);
  }

  p.note(
    exportBlock || "No values detected. Set required variables manually.",
    "Deployment export block",
  );

  if (missingRequired.length > 0) {
    p.log.message(
      pc.yellow(
        `Missing required values: ${missingRequired.map((row) => row.key).join(", ")}. Set these before deployment.`,
      ),
    );
  } else {
    p.log.message(pc.green("All required deployment variables are present."));
  }
  p.outro("Done");
}

function collectDeploymentEnvRows(config: PaperclipConfig | null, configPath: string): EnvVarRow[] {
  const agentJwtEnvFile = resolveAgentJwtEnvFile();
  const jwtEnv = readAgentJwtSecretFromEnv();
  const jwtFile = jwtEnv ? null : readAgentJwtSecretFromEnvFile(agentJwtEnvFile);
  const jwtSource = jwtEnv ? "env" : jwtFile ? "file" : "missing";

  const dbUrl = process.env.DATABASE_URL ?? config?.database?.connectionString ?? "";
  const databaseMode = config?.database?.mode ?? "embedded-postgres";
  const dbUrlSource: EnvSource = process.env.DATABASE_URL ? "env" : config?.database?.connectionString ? "config" : "missing";

  const heartbeatInterval = process.env.HEARTBEAT_SCHEDULER_INTERVAL_MS ?? DEFAULT_HEARTBEAT_SCHEDULER_INTERVAL_MS;
  const heartbeatEnabled = process.env.HEARTBEAT_SCHEDULER_ENABLED ?? "true";

  const rows: EnvVarRow[] = [
    {
      key: "PAPERCLIP_AGENT_JWT_SECRET",
      value: jwtEnv ?? jwtFile ?? "",
      source: jwtSource,
      required: true,
      note:
        jwtSource === "missing"
          ? "Generate during onboard or set manually (required for local adapter authentication)"
          : jwtSource === "env"
            ? "Set in process environment"
            : `Set in ${agentJwtEnvFile}`,
    },
    {
      key: "DATABASE_URL",
      value: dbUrl,
      source: dbUrlSource,
      required: true,
      note:
        databaseMode === "postgres"
          ? "Configured for postgres mode (required)"
          : "Required for live deployment with managed PostgreSQL",
    },
    {
      key: "PORT",
      value:
        process.env.PORT ??
        (config?.server?.port !== undefined ? String(config.server.port) : "3100"),
      source: process.env.PORT ? "env" : config?.server?.port !== undefined ? "config" : "default",
      required: false,
      note: "HTTP listen port",
    },
    {
      key: "PAPERCLIP_AGENT_JWT_TTL_SECONDS",
      value: process.env.PAPERCLIP_AGENT_JWT_TTL_SECONDS ?? DEFAULT_AGENT_JWT_TTL_SECONDS,
      source: process.env.PAPERCLIP_AGENT_JWT_TTL_SECONDS ? "env" : "default",
      required: false,
      note: "JWT lifetime in seconds",
    },
    {
      key: "PAPERCLIP_AGENT_JWT_ISSUER",
      value: process.env.PAPERCLIP_AGENT_JWT_ISSUER ?? DEFAULT_AGENT_JWT_ISSUER,
      source: process.env.PAPERCLIP_AGENT_JWT_ISSUER ? "env" : "default",
      required: false,
      note: "JWT issuer",
    },
    {
      key: "PAPERCLIP_AGENT_JWT_AUDIENCE",
      value: process.env.PAPERCLIP_AGENT_JWT_AUDIENCE ?? DEFAULT_AGENT_JWT_AUDIENCE,
      source: process.env.PAPERCLIP_AGENT_JWT_AUDIENCE ? "env" : "default",
      required: false,
      note: "JWT audience",
    },
    {
      key: "HEARTBEAT_SCHEDULER_INTERVAL_MS",
      value: heartbeatInterval,
      source: process.env.HEARTBEAT_SCHEDULER_INTERVAL_MS ? "env" : "default",
      required: false,
      note: "Heartbeat worker interval in ms",
    },
    {
      key: "HEARTBEAT_SCHEDULER_ENABLED",
      value: heartbeatEnabled,
      source: process.env.HEARTBEAT_SCHEDULER_ENABLED ? "env" : "default",
      required: false,
      note: "Set to `false` to disable timer scheduling",
    },
  ];

  const defaultConfigPath = resolveConfigPath();
  if (process.env.PAPERCLIP_CONFIG || configPath !== defaultConfigPath) {
    rows.push({
      key: "PAPERCLIP_CONFIG",
      value: process.env.PAPERCLIP_CONFIG ?? configPath,
      source: process.env.PAPERCLIP_CONFIG ? "env" : "default",
      required: false,
      note: "Optional path override for config file",
    });
  }

  return rows;
}

function uniqueByKey(rows: EnvVarRow[]): EnvVarRow[] {
  const seen = new Set<string>();
  const result: EnvVarRow[] = [];
  for (const row of rows) {
    if (seen.has(row.key)) continue;
    seen.add(row.key);
    result.push(row);
  }
  return result;
}

function quoteShellValue(value: string): string {
  if (value === "") return "\"\"";
  return `'${value.replaceAll("'", "'\\''")}'`;
}