package tools_test

import (
	"context"
	"encoding/json"
	"io"
	"net/http"
	"net/http/httptest"
	"testing"

	"git.d-ma.be/mathias/gitea-mcp/internal/allowlist"
	"git.d-ma.be/mathias/gitea-mcp/internal/gitea"
	"git.d-ma.be/mathias/gitea-mcp/internal/tools"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

const labelListFixture = `[
	{"id":1,"name":"bug","color":"ee0701"},
	{"id":2,"name":"enhancement","color":"84b6eb"}
]`

func TestIssueLabelAppliesByName(t *testing.T) {
	var captured []byte
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		switch {
		case r.Method == http.MethodGet && r.URL.Path == "/api/v1/repos/o/r/labels":
			w.Header().Set("Content-Type", "application/json")
			_, _ = w.Write([]byte(labelListFixture))
		case r.Method == http.MethodPost && r.URL.Path == "/api/v1/repos/o/r/issues/42/labels":
			var err error
			captured, err = io.ReadAll(r.Body)
			require.NoError(t, err)
			w.Header().Set("Content-Type", "application/json")
			_, _ = w.Write([]byte(labelListFixture))
		default:
			t.Fatalf("unexpected request: %s %s", r.Method, r.URL.Path)
		}
	}))
	defer srv.Close()

	tool := tools.NewIssueLabel(gitea.NewClient(srv.URL, "tok"), allowlist.New([]string{"o"}))
	out, err := tool.Call(context.Background(), json.RawMessage(`{"owner":"o","repo":"r","number":42,"labels":["bug","enhancement"]}`))
	require.NoError(t, err)

	var payload map[string]any
	require.NoError(t, json.Unmarshal(captured, &payload))
	ids, ok := payload["labels"].([]any)
	require.True(t, ok)
	assert.ElementsMatch(t, []any{float64(1), float64(2)}, ids)

	assert.Contains(t, string(out), `"name":"bug"`)
	assert.Contains(t, string(out), `"name":"enhancement"`)
}

// label_ids alone (no labels) must work end-to-end without hitting ListLabels
// at all — this is the schema-level "either labels or label_ids" contract, and
// it must never require a GET to the label list when the caller already has IDs.
func TestIssueLabelAppliesByIDOnly(t *testing.T) {
	var captured []byte
	var listCalled bool
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		switch {
		case r.Method == http.MethodGet && r.URL.Path == "/api/v1/repos/o/r/labels":
			listCalled = true
			w.Header().Set("Content-Type", "application/json")
			_, _ = w.Write([]byte(labelListFixture))
		case r.Method == http.MethodPost && r.URL.Path == "/api/v1/repos/o/r/issues/42/labels":
			var err error
			captured, err = io.ReadAll(r.Body)
			require.NoError(t, err)
			w.Header().Set("Content-Type", "application/json")
			_, _ = w.Write([]byte(labelListFixture))
		default:
			t.Fatalf("unexpected request: %s %s", r.Method, r.URL.Path)
		}
	}))
	defer srv.Close()

	tool := tools.NewIssueLabel(gitea.NewClient(srv.URL, "tok"), allowlist.New([]string{"o"}))
	out, err := tool.Call(context.Background(), json.RawMessage(`{"owner":"o","repo":"r","number":42,"label_ids":[1,2]}`))
	require.NoError(t, err)

	assert.False(t, listCalled, "label_ids-only must not call ListLabels")
	var payload map[string]any
	require.NoError(t, json.Unmarshal(captured, &payload))
	ids, ok := payload["labels"].([]any)
	require.True(t, ok)
	assert.ElementsMatch(t, []any{float64(1), float64(2)}, ids)
	assert.Contains(t, string(out), `"name":"bug"`)
}

// #52 review finding: the advertised schema wrongly required "labels", making
// label_ids-only calls fail JSON-Schema validation before reaching Call at all.
// Lock the fixed contract: neither is individually required.
func TestIssueLabelSchema_NeitherLabelsNorLabelIDsRequired(t *testing.T) {
	sch := string(tools.NewIssueLabel(gitea.NewClient("http://unused", ""), allowlist.New([]string{"o"})).Descriptor().InputSchema)
	assert.NotContains(t, sch, `"required":["owner","repo","number","labels"]`)
	assert.Contains(t, sch, `"required":["owner","repo","number"]`)
}

func TestIssueLabelUnknownNameNamesTheMissingLabel(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		_, _ = w.Write([]byte(labelListFixture))
	}))
	defer srv.Close()

	tool := tools.NewIssueLabel(gitea.NewClient(srv.URL, "tok"), allowlist.New([]string{"o"}))
	_, err := tool.Call(context.Background(), json.RawMessage(`{"owner":"o","repo":"r","number":42,"labels":["bug","does-not-exist"]}`))
	require.Error(t, err)
	assert.ErrorIs(t, err, gitea.ErrValidation)
	assert.Contains(t, err.Error(), `"does-not-exist"`)
	assert.Contains(t, err.Error(), "o/r")
}

func TestIssueLabelAllowlistRejects(t *testing.T) {
	tool := tools.NewIssueLabel(gitea.NewClient("http://unused", ""), allowlist.New([]string{"allowed"}))
	_, err := tool.Call(context.Background(), json.RawMessage(`{"owner":"evil","repo":"r","number":1,"labels":["bug"]}`))
	require.Error(t, err)
}

func TestIssueLabelRequiresValidNumber(t *testing.T) {
	tool := tools.NewIssueLabel(gitea.NewClient("http://unused", ""), allowlist.New([]string{"o"}))
	_, err := tool.Call(context.Background(), json.RawMessage(`{"owner":"o","repo":"r","number":0,"labels":["bug"]}`))
	require.Error(t, err)
	assert.ErrorIs(t, err, gitea.ErrValidation)
}