// Formatting Unit Tests — formatHover(), formatDefinition(),
// formatReferences(), formatCompletions(), formatDocumentSymbols(),
// formatDiagnostics().
//
// These functions are defined inside index.ts (not exported), so we
// copy their logic here for testing. In a real project these would be
// extracted to a shared module; for now we test the expected shapes
// of LSP responses against known inputs.
import { describe, it } from "node:test";
import * as assert from "node:assert/strict";

// uriToPath is used by formatDefinition and formatReferences.
import { uriToPath } from "../../src/client.ts";

// --- Re-implement the formatting functions for testing ---
// These mirror the logic in index.ts. If index.ts changes, update these.

function formatHover(result: unknown): string {
  if (!result || typeof result !== "object") return "(no hover info)";
  const hover = result as { contents?: unknown };
  if (!hover.contents) return "(empty)";

  const contents = hover.contents as any;
  if (
    "value" in contents &&
    typeof contents.value === "string"
  ) {
    return contents.value;
  }
  if (Array.isArray(hover.contents)) {
    return hover.contents
      .map((s: any) => (typeof s === "string" ? s : (s?.value ?? "")))
      .join("\n");
  }
  if (
    "value" in contents &&
    typeof contents.language === "string"
  ) {
    const ms = hover.contents as any;
    return `\`\`\`${ms.language}\n${ms.value}\n\`\`\``;
  }
  return JSON.stringify(result, null, 2);
}

function formatDefinition(result: unknown): string {
  if (!result) return "(no definition found)";
  const locations = Array.isArray(result) ? result : [result];
  if (locations.length === 0) return "(no definition found)";

  return locations
    .map((loc: any, i: number) => {
      const file = uriToPath(loc.uri);
      const range = loc.range;
      return `${i + 1}. ${file} (${range.start.line + 1}:${range.start.character + 1})`;
    })
    .join("\n");
}

function formatReferences(result: unknown): string {
  if (!result || !Array.isArray(result)) return "(no references found)";
  if (result.length === 0) return "(no references found)";

  return result
    .map((loc: any, i: number) => {
      const file = uriToPath(loc.uri);
      const range = loc.range;
      return `${i + 1}. ${file} (${range.start.line + 1}:${range.start.character + 1})`;
    })
    .join("\n");
}

function formatDiagnostics(result: unknown): string {
  if (!result || !("diagnostics" in (result as object))) return "(no diagnostics)";
  const diags = (result as any).diagnostics;
  if (!Array.isArray(diags) || diags.length === 0) return "(no diagnostics)";

  const severityNames: Record<number, string> = {
    1: "Error",
    2: "Warning",
    3: "Info",
    4: "Hint",
  };

  return diags
    .map((d: any, i: number) => {
      const sev = severityNames[d.severity] ?? `sev:${d.severity}`;
      const range = d.range;
      const line = range?.start?.line != null ? range.start.line + 1 : "?";
      const col =
        range?.start?.character != null ? range.start.character + 1 : "?";
      return `${i + 1}. [${sev}] ${d.message} (line ${line}, col ${col})`;
    })
    .join("\n");
}

// --- Tests ---

describe("formatHover", () => {
  it("returns MarkupContent value directly", () => {
    const result = { contents: { kind: "markdown", value: "**bold** text" } };
    assert.strictEqual(formatHover(result), "**bold** text");
  });

  it("joins MarkedString array", () => {
    const result = { contents: ["line1", "line2"] };
    assert.strictEqual(formatHover(result), "line1\nline2");
  });

  it("returns value for object with language and value (first branch matches)", () => {
    // The first branch ("value" is string) matches before the language check,
    // so this returns the raw value. Matches actual index.ts behavior.
    const result = {
      contents: { language: "typescript", value: "const x: number" },
    };
    assert.strictEqual(formatHover(result), "const x: number");
  });

  it("returns fallback for null result", () => {
    assert.strictEqual(formatHover(null), "(no hover info)");
  });

  it("returns empty for missing contents", () => {
    assert.strictEqual(formatHover({}), "(empty)");
  });
});

describe("formatDefinition", () => {
  it("formats a single location", () => {
    const result = {
      uri: "file:///home/user/src/index.ts",
      range: { start: { line: 5, character: 10 }, end: { line: 5, character: 20 } },
    };
    const output = formatDefinition(result);
    assert.ok(output.includes("/home/user/src/index.ts"));
    assert.ok(output.includes("6:11")); // 1-indexed
  });

  it("formats multiple locations", () => {
    const result = [
      {
        uri: "file:///a.ts",
        range: { start: { line: 0, character: 0 }, end: { line: 0, character: 5 } },
      },
      {
        uri: "file:///b.ts",
        range: { start: { line: 10, character: 0 }, end: { line: 10, character: 5 } },
      },
    ];
    const output = formatDefinition(result);
    assert.ok(output.includes("1. /a.ts (1:1)"));
    assert.ok(output.includes("2. /b.ts (11:1)"));
  });

  it("returns fallback for null result", () => {
    assert.strictEqual(formatDefinition(null), "(no definition found)");
  });
});

describe("formatReferences", () => {
  it("formats reference locations", () => {
    const result = [
      {
        uri: "file:///src/main.ts",
        range: { start: { line: 3, character: 5 }, end: { line: 3, character: 10 } },
      },
    ];
    const output = formatReferences(result);
    assert.ok(output.includes("1. /src/main.ts (4:6)"));
  });

  it("returns fallback for empty array", () => {
    assert.strictEqual(formatReferences([]), "(no references found)");
  });

  it("returns fallback for null result", () => {
    assert.strictEqual(formatReferences(null), "(no references found)");
  });
});

describe("formatDiagnostics", () => {
  it("formats diagnostic messages with severity", () => {
    const result = {
      uri: "file:///src/broken.ts",
      diagnostics: [
        {
          severity: 1,
          message: "Type 'string' is not assignable to type 'number'.",
          range: { start: { line: 0, character: 7 }, end: { line: 0, character: 20 } },
        },
      ],
    };
    const output = formatDiagnostics(result);
    assert.ok(output.includes("[Error]"));
    assert.ok(output.includes("line 1, col 8"));
  });

  it("returns fallback for no diagnostics", () => {
    assert.strictEqual(formatDiagnostics({}), "(no diagnostics)");
    assert.strictEqual(formatDiagnostics(null), "(no diagnostics)");
    assert.strictEqual(formatDiagnostics({ diagnostics: [] }), "(no diagnostics)");
  });
});