/**
 * executionPlanner.test.ts — S415 test suite
 *
 * Copre:
 *  - buildExecutionPlan(goal, spec, arch) → ExecutionPlan
 *  - formatExecutionPlan(plan) → string
 *  - formatExecutionPlanCompact(plan) → string
 *  - Ordinamento layer: auth → database → backend → frontend → integration
 *  - Assegnazione reqIds per layer
 *  - isMinimal per goal semplici
 *  - criticalPath esclude integration steps
 */

import { describe, it, expect } from "vitest";
import { buildExecutionPlan, formatExecutionPlan, formatExecutionPlanCompact } from "../executionPlanner";
import { decomposeGoal }    from "../requirementDecomposer";
import { planArchitecture } from "../architecturePlanner";
import type { GoalSpec }          from "../requirementDecomposer";
import type { ArchitecturePlan }  from "../architecturePlanner";

// ─── helper per costruire spec/arch minimali senza LLM ────────────────────────

function makeSpec(reqs: Array<{ feature: string; priority?: string }>): GoalSpec {
  return {
    goal:         "test goal",
    requirements: reqs.map((r, i) => ({
      id:                 `REQ-${String(i + 1).padStart(3, "0")}`,
      feature:            r.feature,
      priority:           (r.priority ?? "high") as "critical" | "high" | "normal",
      acceptanceCriteria: [`${r.feature} funzionante`],
    })),
    complexity: reqs.length >= 4 ? "high" : reqs.length >= 2 ? "medium" : "low",
  };
}

function makeArch(layers: Array<import("../architecturePlanner").LayerType>): ArchitecturePlan {
  return {
    goal:       "test goal",
    nodes:      layers.map((layer, i) => ({
      id:          `node-${i}`,
      layer,
      name:        `${layer.charAt(0).toUpperCase()}${layer.slice(1)} Service`,
      tech:        "generic",
      description: "",
    })),
    edges:      [],
    entryPoint: layers[0] ?? "frontend",
  };
}

// ─── 1. buildExecutionPlan — ordinamento layer ─────────────────────────────────

describe("buildExecutionPlan — ordinamento layer", () => {
  it("auth → database → backend → frontend (ordine garantito)", () => {
    const spec = makeSpec([
      { feature: "Auth/Login", priority: "critical" },
      { feature: "Database schema", priority: "high" },
      { feature: "API REST", priority: "high" },
      { feature: "Dashboard UI", priority: "normal" },
    ]);
    const arch = makeArch(["auth", "database", "backend", "frontend"]);
    const plan = buildExecutionPlan("test", spec, arch);

    const layers = plan.steps.map(s => s.layer);
    const authIdx     = layers.indexOf("auth");
    const dbIdx       = layers.indexOf("database");
    const backendIdx  = layers.indexOf("backend");
    const frontendIdx = layers.indexOf("frontend");

    expect(authIdx).toBeLessThan(dbIdx);
    expect(dbIdx).toBeLessThan(backendIdx);
    expect(backendIdx).toBeLessThan(frontendIdx);
  });

  it("integration steps vengono DOPO backend", () => {
    const spec = makeSpec([
      { feature: "Backend API" },
      { feature: "Redis cache" },
    ]);
    const arch = makeArch(["backend", "cache"]);
    const plan = buildExecutionPlan("test", spec, arch);

    const backendIdx     = plan.steps.findIndex(s => s.layer === "backend");
    const integrationIdx = plan.steps.findIndex(s => s.layer === "integration");
    if (backendIdx >= 0 && integrationIdx >= 0) {
      expect(backendIdx).toBeLessThan(integrationIdx);
    }
  });

  it("senza auth nell'arch, ordine inizia da database o backend", () => {
    const spec = makeSpec([{ feature: "Database schema" }, { feature: "API" }]);
    const arch = makeArch(["database", "backend"]);
    const plan = buildExecutionPlan("test", spec, arch);
    expect(plan.steps[0].layer).toBe("database");
  });
});

// ─── 2. buildExecutionPlan — struttura ExecutionPlan ──────────────────────────

describe("buildExecutionPlan — struttura output", () => {
  it("plan ha goal, steps, criticalPath, totalSteps, isMinimal, estimatedComplexity", () => {
    const spec = makeSpec([{ feature: "Login" }, { feature: "CRUD" }]);
    const arch = makeArch(["auth", "database"]);
    const plan = buildExecutionPlan("app con login e CRUD", spec, arch);

    expect(plan).toHaveProperty("goal");
    expect(plan).toHaveProperty("steps");
    expect(plan).toHaveProperty("criticalPath");
    expect(plan).toHaveProperty("totalSteps");
    expect(plan).toHaveProperty("isMinimal");
    expect(plan).toHaveProperty("estimatedComplexity");
    expect(plan.totalSteps).toBe(plan.steps.length);
  });

  it("ogni step ha order, name, layer, purpose, filesToCreate, verifyHint, deps, isCritical", () => {
    const spec = makeSpec([{ feature: "Auth" }, { feature: "Database" }]);
    const arch = makeArch(["auth", "database"]);
    const plan = buildExecutionPlan("test", spec, arch);

    for (const step of plan.steps) {
      expect(step).toHaveProperty("order");
      expect(step).toHaveProperty("name");
      expect(step).toHaveProperty("layer");
      expect(step).toHaveProperty("purpose");
      expect(step).toHaveProperty("filesToCreate");
      expect(step).toHaveProperty("verifyHint");
      expect(step).toHaveProperty("deps");
      expect(step).toHaveProperty("isCritical");
      expect(Array.isArray(step.filesToCreate)).toBe(true);
      expect(Array.isArray(step.deps)).toBe(true);
    }
  });

  it("steps ordinati per order (0, 1, 2...)", () => {
    const spec = makeSpec([
      { feature: "Auth" }, { feature: "DB" }, { feature: "API" }, { feature: "UI" },
    ]);
    const arch = makeArch(["auth", "database", "backend", "frontend"]);
    const plan = buildExecutionPlan("test", spec, arch);

    const orders = plan.steps.map(s => s.order);
    for (let i = 0; i < orders.length; i++) {
      expect(orders[i]).toBe(i);
    }
  });

  it("integration step ha isCritical = false", () => {
    const spec = makeSpec([{ feature: "Redis caching" }]);
    const arch = makeArch(["cache"]);
    const plan = buildExecutionPlan("test", spec, arch);
    const integStep = plan.steps.find(s => s.layer === "integration");
    if (integStep) {
      expect(integStep.isCritical).toBe(false);
    }
  });

  it("auth step ha isCritical = true", () => {
    const spec = makeSpec([{ feature: "Login" }]);
    const arch = makeArch(["auth"]);
    const plan = buildExecutionPlan("test", spec, arch);
    const authStep = plan.steps.find(s => s.layer === "auth");
    if (authStep) {
      expect(authStep.isCritical).toBe(true);
    }
  });
});

// ─── 3. isMinimal ─────────────────────────────────────────────────────────────

describe("buildExecutionPlan — isMinimal", () => {
  it("piano con 1 step → isMinimal = true", () => {
    const spec = makeSpec([{ feature: "UI semplice" }]);
    const arch = makeArch(["frontend"]);
    const plan = buildExecutionPlan("test", spec, arch);
    expect(plan.isMinimal).toBe(plan.totalSteps < 2);
  });

  it("piano con ≥2 step → isMinimal = false", () => {
    const spec = makeSpec([{ feature: "Auth" }, { feature: "Database" }]);
    const arch = makeArch(["auth", "database"]);
    const plan = buildExecutionPlan("test", spec, arch);
    if (plan.totalSteps >= 2) expect(plan.isMinimal).toBe(false);
  });
});

// ─── 4. estimatedComplexity ────────────────────────────────────────────────────

describe("buildExecutionPlan — estimatedComplexity", () => {
  it("≥4 step → high", () => {
    const spec = makeSpec([
      { feature: "Auth" }, { feature: "DB" }, { feature: "API" }, { feature: "UI" },
    ]);
    const arch = makeArch(["auth", "database", "backend", "frontend"]);
    const plan = buildExecutionPlan("test", spec, arch);
    if (plan.totalSteps >= 4) expect(plan.estimatedComplexity).toBe("high");
  });

  it("2-3 step → medium", () => {
    const spec = makeSpec([{ feature: "DB" }, { feature: "API" }]);
    const arch = makeArch(["database", "backend"]);
    const plan = buildExecutionPlan("test", spec, arch);
    if (plan.totalSteps >= 2 && plan.totalSteps < 4) {
      expect(["medium", "high"]).toContain(plan.estimatedComplexity);
    }
  });
});

// ─── 5. criticalPath ──────────────────────────────────────────────────────────

describe("buildExecutionPlan — criticalPath", () => {
  it("criticalPath contiene solo step non-integration", () => {
    const spec = makeSpec([
      { feature: "Auth" }, { feature: "Backend" }, { feature: "Redis" },
    ]);
    const arch = makeArch(["auth", "backend", "cache"]);
    const plan = buildExecutionPlan("test", spec, arch);
    for (const idx of plan.criticalPath) {
      expect(plan.steps[idx]?.isCritical).toBe(true);
    }
  });
});

// ─── 6. formatExecutionPlan ───────────────────────────────────────────────────

describe("formatExecutionPlan", () => {
  it("piano isMinimal → stringa vuota", () => {
    const plan = buildExecutionPlan("test", makeSpec([{ feature: "UI" }]), makeArch(["frontend"]));
    if (plan.isMinimal) {
      expect(formatExecutionPlan(plan)).toBe("");
    }
  });

  it("piano con ≥2 step → contiene [STEP N]", () => {
    const spec = makeSpec([{ feature: "Auth" }, { feature: "Database" }]);
    const arch = makeArch(["auth", "database"]);
    const plan = buildExecutionPlan("test", spec, arch);
    if (!plan.isMinimal) {
      const text = formatExecutionPlan(plan);
      expect(text).toMatch(/\[STEP \d\]/);
      expect(text).toContain("Checkpoint");
      expect(text).toContain("REGOLA");
    }
  });

  it("output contiene il critical path", () => {
    const spec = makeSpec([{ feature: "Auth" }, { feature: "Database" }]);
    const arch = makeArch(["auth", "database"]);
    const plan = buildExecutionPlan("test", spec, arch);
    if (!plan.isMinimal) {
      expect(formatExecutionPlan(plan)).toContain("Critical path");
    }
  });

  it("ogni step contiene verifyHint nel testo", () => {
    const spec = makeSpec([{ feature: "Auth" }, { feature: "API" }]);
    const arch = makeArch(["auth", "backend"]);
    const plan = buildExecutionPlan("test", spec, arch);
    if (!plan.isMinimal) {
      const text = formatExecutionPlan(plan);
      expect(text).toMatch(/Verifica:/);
    }
  });
});

// ─── 7. formatExecutionPlanCompact ────────────────────────────────────────────

describe("formatExecutionPlanCompact", () => {
  it("piano isMinimal → stringa vuota", () => {
    const plan = buildExecutionPlan("test", makeSpec([{ feature: "UI" }]), makeArch(["frontend"]));
    if (plan.isMinimal) {
      expect(formatExecutionPlanCompact(plan)).toBe("");
    }
  });

  it("piano con ≥2 step → contiene 🗺️ e step names", () => {
    const spec = makeSpec([{ feature: "Auth" }, { feature: "Database" }]);
    const arch = makeArch(["auth", "database"]);
    const plan = buildExecutionPlan("test", spec, arch);
    if (!plan.isMinimal) {
      const compact = formatExecutionPlanCompact(plan);
      expect(compact).toContain("🗺️");
      expect(compact).toContain("→");
    }
  });

  it("compact è più corto di full", () => {
    const spec = makeSpec([{ feature: "Auth" }, { feature: "DB" }, { feature: "API" }]);
    const arch = makeArch(["auth", "database", "backend"]);
    const plan = buildExecutionPlan("test", spec, arch);
    if (!plan.isMinimal) {
      expect(formatExecutionPlanCompact(plan).length).toBeLessThan(formatExecutionPlan(plan).length);
    }
  });
});

// ─── 8. Integrazione con decomposeGoal + planArchitecture ─────────────────────

describe("buildExecutionPlan — integrazione decomposeGoal + planArchitecture", () => {
  it("goal 'app con login, database e dashboard' → piano ordinato auth→db→frontend", () => {
    const goal = "Crea app con login JWT, schema PostgreSQL e dashboard React";
    const spec  = decomposeGoal(goal);
    const arch  = planArchitecture(goal, spec.requirements);
    const plan  = buildExecutionPlan(goal, spec, arch);

    expect(plan.steps.length).toBeGreaterThan(0);
    expect(plan.goal).toBe(goal);
    // Auth deve venire prima di database se entrambi presenti
    const layers = plan.steps.map(s => s.layer);
    const authIdx = layers.indexOf("auth");
    const dbIdx   = layers.indexOf("database");
    if (authIdx >= 0 && dbIdx >= 0) {
      expect(authIdx).toBeLessThan(dbIdx);
    }
  });

  it("goal semplice → piano con almeno 1 step", () => {
    const goal = "Crea una semplice app React";
    const spec  = decomposeGoal(goal);
    const arch  = planArchitecture(goal, spec.requirements);
    const plan  = buildExecutionPlan(goal, spec, arch);
    expect(plan.steps.length).toBeGreaterThanOrEqual(1);
  });
});