import { basename } from "node:path";
import { AgenticError } from "../core/errors";

export type PlanStepKind = "edit" | "command" | "vcs" | "research" | "other";
export type PlanChange = "create" | "modify" | "delete" | "move";

export interface PlanStep {
  n: number;
  text: string;
  kind?: PlanStepKind;
}

export interface PlanFileChange {
  path: string;
  change: PlanChange;
}

export interface PlanCommand {
  executable: string;
  args: string[];
}

export interface PlanDocument {
  title: string;
  objective: string;
  steps: PlanStep[];
  files: PlanFileChange[];
  commands: PlanCommand[];
  risks: string[];
  questions: string[];
  revision: number;
  supersedes?: string;
}

export interface PlanInput {
  title: string;
  objective: string;
  steps: Array<string | { text: string; kind?: PlanStepKind }>;
  files?: Array<{ path: string; change: PlanChange }>;
  commands?: Array<{ executable: string; args?: string[] }>;
  risks?: string[];
  questions?: string[];
}

const MAX_STEPS = 40;
const MAX_FILES = 100;
const MAX_COMMANDS = 40;
const MAX_TEXT = 2000;

function text(value: unknown, field: string, required = true): string {
  const normalized = typeof value === "string" ? value.trim() : "";
  if (required && !normalized) {
    throw new AgenticError("INVALID_INPUT", `Plan ${field} may not be empty.`);
  }
  if (normalized.length > MAX_TEXT) {
    throw new AgenticError("INVALID_INPUT", `Plan ${field} is limited to ${MAX_TEXT} characters.`);
  }
  return normalized;
}

function textList(values: string[] | undefined, field: string, max: number): string[] {
  const list = (values ?? []).map((value, index) => text(value, `${field}[${index}]`));
  if (list.length > max) {
    throw new AgenticError("INVALID_INPUT", `Plan ${field} is limited to ${max} entries.`);
  }
  return list;
}

export function validatePlan(
  input: PlanInput,
  options: { revision?: number; supersedes?: string } = {},
): PlanDocument {
  const steps = (input.steps ?? []).map((step, index) => {
    const raw = typeof step === "string" ? { text: step } : step;
    return {
      n: index + 1,
      text: text(raw.text, `steps[${index}]`),
      ...(raw.kind ? { kind: raw.kind } : {}),
    };
  });
  if (steps.length === 0) {
    throw new AgenticError("INVALID_INPUT", "A plan needs at least one step.");
  }
  if (steps.length > MAX_STEPS) {
    throw new AgenticError("INVALID_INPUT", `A plan is limited to ${MAX_STEPS} steps.`);
  }
  const files = (input.files ?? []).map((file, index) => ({
    path: text(file.path, `files[${index}].path`),
    change: file.change,
  }));
  if (files.length > MAX_FILES) {
    throw new AgenticError("INVALID_INPUT", `A plan is limited to ${MAX_FILES} files.`);
  }
  const commands = (input.commands ?? []).map((command, index) => {
    const executable = text(command.executable, `commands[${index}].executable`);
    if (executable !== basename(executable) || /[\\/]/.test(executable)) {
      throw new AgenticError(
        "INVALID_INPUT",
        `Plan command ${index + 1} must name a bare allowlisted executable.`,
      );
    }
    return { executable, args: (command.args ?? []).map((arg) => String(arg)) };
  });
  if (commands.length > MAX_COMMANDS) {
    throw new AgenticError("INVALID_INPUT", `A plan is limited to ${MAX_COMMANDS} commands.`);
  }
  return {
    title: text(input.title, "title"),
    objective: text(input.objective, "objective"),
    steps,
    files,
    commands,
    risks: textList(input.risks, "risks", MAX_STEPS),
    questions: textList(input.questions, "questions", MAX_STEPS),
    revision: options.revision ?? 1,
    ...(options.supersedes ? { supersedes: options.supersedes } : {}),
  };
}

export function renderPlanMarkdown(plan: PlanDocument, id: string): string {
  const heading = plan.supersedes
    ? `# Plan ${id}: ${plan.title} (revision ${plan.revision}, supersedes ${plan.supersedes})`
    : `# Plan ${id}: ${plan.title} (revision ${plan.revision})`;
  const sections: string[] = [heading, "", "## Objective", plan.objective, ""];
  sections.push("## Steps");
  for (const step of plan.steps) {
    sections.push(`${step.n}. ${step.text}${step.kind ? ` _(${step.kind})_` : ""}`);
  }
  sections.push("");
  if (plan.files.length > 0) {
    sections.push("## Files");
    for (const file of plan.files) sections.push(`- ${file.change}: ${file.path}`);
    sections.push("");
  }
  if (plan.commands.length > 0) {
    sections.push("## Commands");
    for (const command of plan.commands) {
      sections.push(`- ${[command.executable, ...command.args].join(" ")}`);
    }
    sections.push("");
  }
  if (plan.risks.length > 0) {
    sections.push("## Risks");
    for (const risk of plan.risks) sections.push(`- ${risk}`);
    sections.push("");
  }
  if (plan.questions.length > 0) {
    sections.push("## Open questions");
    for (const question of plan.questions) sections.push(`- ${question}`);
    sections.push("");
  }
  return `${sections.join("\n").replace(/\n+$/, "")}\n`;
}

import { basename } from "node:path";
import { AgenticError } from "../core/errors";

export type PlanStepKind = "edit" | "command" | "vcs" | "research" | "other";
export type PlanChange = "create" | "modify" | "delete" | "move";

export interface PlanStep {
  n: number;
  text: string;
  kind?: PlanStepKind;
}

export interface PlanFileChange {
  path: string;
  change: PlanChange;
}

export interface PlanCommand {
  executable: string;
  args: string[];
}

export interface PlanDocument {
  title: string;
  objective: string;
  steps: PlanStep[];
  files: PlanFileChange[];
  commands: PlanCommand[];
  risks: string[];
  questions: string[];
  revision: number;
  supersedes?: string;
}

export interface PlanInput {
  title: string;
  objective: string;
  steps: Array<string | { text: string; kind?: PlanStepKind }>;
  files?: Array<{ path: string; change: PlanChange }>;
  commands?: Array<{ executable: string; args?: string[] }>;
  risks?: string[];
  questions?: string[];
}

const MAX_STEPS = 40;
const MAX_FILES = 100;
const MAX_COMMANDS = 40;
const MAX_TEXT = 2000;

function text(value: unknown, field: string, required = true): string {
  const normalized = typeof value === "string" ? value.trim() : "";
  if (required && !normalized) {
    throw new AgenticError("INVALID_INPUT", `Plan ${field} may not be empty.`);
  }
  if (normalized.length > MAX_TEXT) {
    throw new AgenticError("INVALID_INPUT", `Plan ${field} is limited to ${MAX_TEXT} characters.`);
  }
  return normalized;
}

function textList(values: string[] | undefined, field: string, max: number): string[] {
  const list = (values ?? []).map((value, index) => text(value, `${field}[${index}]`));
  if (list.length > max) {
    throw new AgenticError("INVALID_INPUT", `Plan ${field} is limited to ${max} entries.`);
  }
  return list;
}

export function validatePlan(
  input: PlanInput,
  options: { revision?: number; supersedes?: string } = {},
): PlanDocument {
  const steps = (input.steps ?? []).map((step, index) => {
    const raw = typeof step === "string" ? { text: step } : step;
    return {
      n: index + 1,
      text: text(raw.text, `steps[${index}]`),
      ...(raw.kind ? { kind: raw.kind } : {}),
    };
  });
  if (steps.length === 0) {
    throw new AgenticError("INVALID_INPUT", "A plan needs at least one step.");
  }
  if (steps.length > MAX_STEPS) {
    throw new AgenticError("INVALID_INPUT", `A plan is limited to ${MAX_STEPS} steps.`);
  }
  const files = (input.files ?? []).map((file, index) => ({
    path: text(file.path, `files[${index}].path`),
    change: file.change,
  }));
  if (files.length > MAX_FILES) {
    throw new AgenticError("INVALID_INPUT", `A plan is limited to ${MAX_FILES} files.`);
  }
  const commands = (input.commands ?? []).map((command, index) => {
    const executable = text(command.executable, `commands[${index}].executable`);
    if (executable !== basename(executable) || /[\\/]/.test(executable)) {
      throw new AgenticError(
        "INVALID_INPUT",
        `Plan command ${index + 1} must name a bare allowlisted executable.`,
      );
    }
    return { executable, args: (command.args ?? []).map((arg) => String(arg)) };
  });
  if (commands.length > MAX_COMMANDS) {
    throw new AgenticError("INVALID_INPUT", `A plan is limited to ${MAX_COMMANDS} commands.`);
  }
  return {
    title: text(input.title, "title"),
    objective: text(input.objective, "objective"),
    steps,
    files,
    commands,
    risks: textList(input.risks, "risks", MAX_STEPS),
    questions: textList(input.questions, "questions", MAX_STEPS),
    revision: options.revision ?? 1,
    ...(options.supersedes ? { supersedes: options.supersedes } : {}),
  };
}

export function renderPlanMarkdown(plan: PlanDocument, id: string): string {
  const heading = plan.supersedes
    ? `# Plan ${id}: ${plan.title} (revision ${plan.revision}, supersedes ${plan.supersedes})`
    : `# Plan ${id}: ${plan.title} (revision ${plan.revision})`;
  const sections: string[] = [heading, "", "## Objective", plan.objective, ""];
  sections.push("## Steps");
  for (const step of plan.steps) {
    sections.push(`${step.n}. ${step.text}${step.kind ? ` _(${step.kind})_` : ""}`);
  }
  sections.push("");
  if (plan.files.length > 0) {
    sections.push("## Files");
    for (const file of plan.files) sections.push(`- ${file.change}: ${file.path}`);
    sections.push("");
  }
  if (plan.commands.length > 0) {
    sections.push("## Commands");
    for (const command of plan.commands) {
      sections.push(`- ${[command.executable, ...command.args].join(" ")}`);
    }
    sections.push("");
  }
  if (plan.risks.length > 0) {
    sections.push("## Risks");
    for (const risk of plan.risks) sections.push(`- ${risk}`);
    sections.push("");
  }
  if (plan.questions.length > 0) {
    sections.push("## Open questions");
    for (const question of plan.questions) sections.push(`- ${question}`);
    sections.push("");
  }
  return `${sections.join("\n").replace(/\n+$/, "")}\n`;
}