// Copyright 2020 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

package analysis_test

import (
	"testing"

	"fidl-lsp/analysis"
	"fidl-lsp/state"
)

func TestReferencesToSymbol(t *testing.T) {
	cases := []struct {
		name    string
		files   map[state.FileID]string
		symbol  state.Symbol
		expRefs []state.Location
	}{
		{
			name: "Reference to library declaration",
			files: map[state.FileID]string{
				"test.fidl": `library fuchsia.test;`,
				"other.fidl": `
library other;
using fuchsia.test;`,
			},
			symbol: state.Symbol{
				Name: "fuchsia.test",
				Location: state.Location{
					FileID: state.FileID("test.fidl"),
					Range: state.Range{
						Start: state.Position{Line: 0, Character: 6},
						End:   state.Position{Line: 0, Character: 10},
					},
				},
			},
			expRefs: []state.Location{
				{
					FileID: state.FileID("other.fidl"),
					Range: state.Range{
						Start: state.Position{Line: 2, Character: 6},
						End:   state.Position{Line: 2, Character: 18},
					},
				},
			},
		},
		{
			name: "Reference to library import",
			files: map[state.FileID]string{
				"test.fidl": `library fuchsia.test;`,
				"other.fidl": `
library other;
using fuchsia.test;`,
			},
			symbol: state.Symbol{
				Name: "fuchsia.test",
				Location: state.Location{
					FileID: state.FileID("test.fidl"),
					Range: state.Range{
						Start: state.Position{Line: 2, Character: 6},
						End:   state.Position{Line: 2, Character: 18},
					},
				},
			},
			expRefs: []state.Location{
				{
					FileID: state.FileID("other.fidl"),
					Range: state.Range{
						Start: state.Position{Line: 2, Character: 6},
						End:   state.Position{Line: 2, Character: 18},
					},
				},
			},
		},
		{
			name: "Reference to symbol in same file",
			files: map[state.FileID]string{
				"test.fidl": `
library test;

struct Foo {};

protocol Bar {
	Method(Foo foo);
//             ~~~
};
`,
			},
			symbol: state.Symbol{
				Name: "Foo",
				Location: state.Location{
					FileID: state.FileID("test.fidl"),
					Range: state.Range{
						Start: state.Position{Line: 3, Character: 7},
						End:   state.Position{Line: 3, Character: 10},
					},
				},
			},
			expRefs: []state.Location{
				{
					FileID: state.FileID("test.fidl"),
					Range: state.Range{
						Start: state.Position{Line: 6, Character: 12},
						End:   state.Position{Line: 6, Character: 15},
					},
				},
			},
		},
		{
			name: "Reference to symbol in other file in same library",
			files: map[state.FileID]string{
				"test1.fidl": `
library test;

struct Foo {};
`,
				"test2.fidl": `
library test;

protocol Bar {
	Method(Foo foo);
//             ~~~
};
`,
			},
			symbol: state.Symbol{
				Name: "Foo",
				Location: state.Location{
					FileID: state.FileID("test1.fidl"),
					Range: state.Range{
						Start: state.Position{Line: 3, Character: 7},
						End:   state.Position{Line: 3, Character: 10},
					},
				},
			},
			expRefs: []state.Location{
				{
					FileID: state.FileID("test2.fidl"),
					Range: state.Range{
						Start: state.Position{Line: 4, Character: 12},
						End:   state.Position{Line: 4, Character: 15},
					},
				},
			},
		},
		{
			name: "References to symbol in other library",
			files: map[state.FileID]string{
				"imported.fidl": `
library fuchsia.imported;

struct Foo {};
`,
				"test.fidl": `
library test;
using fuchsia.imported;

protocol Bar {
	Method(fuchsia.imported.Foo foo);
//                              ~~~
};
`,
			},
			symbol: state.Symbol{
				Name: "Foo",
				Location: state.Location{
					FileID: state.FileID("imported.fidl"),
					Range: state.Range{
						Start: state.Position{Line: 3, Character: 7},
						End:   state.Position{Line: 3, Character: 10},
					},
				},
			},
			expRefs: []state.Location{
				{
					FileID: state.FileID("test.fidl"),
					Range: state.Range{
						Start: state.Position{Line: 5, Character: 29},
						End:   state.Position{Line: 5, Character: 32},
					},
				},
			},
		},
		{
			name: "No references to symbol",
			files: map[state.FileID]string{
				"test.fidl": `
library test;

struct Foo {};
`,
			},
			symbol: state.Symbol{
				Name: "Foo",
				Location: state.Location{
					FileID: state.FileID("test.fidl"),
					Range: state.Range{
						Start: state.Position{Line: 3, Character: 7},
						End:   state.Position{Line: 3, Character: 10},
					},
				},
			},
			expRefs: []state.Location{},
		},
		{
			name: "References to type alias",
			files: map[state.FileID]string{
				"zx.fidl": `
library zx;

using status = int32;
`,
				"test.fidl": `
library test;
using zx;

protocol Foo {
	Method() -> (zx.status status);
//                         ~~~~~~
};
`,
			},
			symbol: state.Symbol{
				Name: "status",
				Location: state.Location{
					FileID: state.FileID("zx.fidl"),
					Range: state.Range{
						Start: state.Position{Line: 3, Character: 7},
						End:   state.Position{Line: 3, Character: 10},
					},
				},
			},
			expRefs: []state.Location{
				{
					FileID: state.FileID("test.fidl"),
					Range: state.Range{
						Start: state.Position{Line: 5, Character: 24},
						End:   state.Position{Line: 5, Character: 30},
					},
				},
			},
		},
		{
			name: "References in type parameters",
			files: map[state.FileID]string{
				"test.fidl": `
library test;

table Foo {};

protocol Bar {
	Method(vector<Foo> items);
//                     ~~~~~
};
`,
			},
			symbol: state.Symbol{
				Name: "Foo",
				Location: state.Location{
					FileID: state.FileID("test.fidl"),
					Range: state.Range{
						Start: state.Position{Line: 3, Character: 6},
						End:   state.Position{Line: 3, Character: 9},
					},
				},
			},
			expRefs: []state.Location{
				{
					FileID: state.FileID("test.fidl"),
					Range: state.Range{
						Start: state.Position{Line: 6, Character: 20},
						End:   state.Position{Line: 6, Character: 25},
					},
				},
			},
		},
	}

	for _, ex := range cases {
		analyzer := analysis.NewAnalyzer(defaultConfig(), analysis.CompiledLibraries{})
		fs := state.NewFileSystem()
		for file, text := range ex.files {
			fs.NewFile(file, text)
		}
		for file := range ex.files {
			if err := analyzer.Analyze(fs, file); err != nil {
				t.Fatalf("case `%s`: failed to analyze file `%s`: %s", ex.name, file, err)
			}
		}

		refs, err := analyzer.ReferencesToSymbol(fs, ex.symbol)
		if err != nil {
			t.Fatalf("case `%s`: error getting references to symbol: %s", ex.name, err)
		}
		if len(refs) != len(ex.expRefs) {
			t.Fatalf("case `%s`: expected %d references, got %d", ex.name, len(ex.expRefs), len(refs))
		}
		for _, ref := range refs {
			found := false
			for _, expRef := range ex.expRefs {
				if ref == expRef {
					found = true
					break
				}
			}
			if !found {
				t.Errorf(
					"case `%s`: got unexpected reference %v to symbol %s",
					ex.name,
					ref,
					ex.symbol.Name,
				)
			}
		}
		for _, expRef := range ex.expRefs {
			found := false
			for _, ref := range refs {
				if ref == expRef {
					found = true
					break
				}
			}
			if !found {
				t.Errorf(
					"case `%s`: expected but did not find reference %v to symbol %s",
					ex.name,
					expRef,
					ex.symbol.Name,
				)
			}
		}
	}
}