package tools_test

import (
	"context"
	"encoding/json"
	"errors"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"

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

func TestCodeSearchSingleRepo(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		assert.Equal(t, "/api/v1/repos/mathias/infra/search", r.URL.Path)
		assert.Equal(t, "ListRepos", r.URL.Query().Get("q"))
		assert.Equal(t, "code", r.URL.Query().Get("type"))
		w.Header().Set("Content-Type", "application/json")
		_, _ = w.Write([]byte(`{
			"data":[{
				"path":"internal/gitea/repos.go",
				"snippet":"func (c *Client) ListRepos",
				"html_url":"http://gitea.example.com/mathias/infra/src/branch/main/internal/gitea/repos.go",
				"score":3.0
			}],
			"ok":true
		}`))
	}))
	defer srv.Close()

	tool := tools.NewCodeSearch(gitea.NewClient(srv.URL, "tok"), allowlist.New([]string{"mathias"}))
	out, err := tool.Call(context.Background(), json.RawMessage(`{"q":"ListRepos","owner":"mathias","repo":"infra"}`))
	require.NoError(t, err)

	var result struct {
		Results []struct {
			Repo    string  `json:"repo"`
			Path    string  `json:"path"`
			Snippet string  `json:"snippet"`
			Score   float64 `json:"score"`
		} `json:"results"`
	}
	require.NoError(t, json.Unmarshal(out, &result))
	require.Len(t, result.Results, 1)
	assert.Equal(t, "mathias/infra", result.Results[0].Repo)
	assert.Equal(t, "internal/gitea/repos.go", result.Results[0].Path)
	assert.Equal(t, "func (c *Client) ListRepos", result.Results[0].Snippet)
}

func TestCodeSearchAllowlistRejects(t *testing.T) {
	tool := tools.NewCodeSearch(gitea.NewClient("http://unused", ""), allowlist.New([]string{"mathias"}))
	_, err := tool.Call(context.Background(), json.RawMessage(`{"q":"foo","owner":"evil","repo":"infra"}`))
	require.Error(t, err)
}

func TestCodeSearchRequiresQ(t *testing.T) {
	tool := tools.NewCodeSearch(gitea.NewClient("http://unused", ""), allowlist.New([]string{"mathias"}))
	_, err := tool.Call(context.Background(), json.RawMessage(`{"owner":"mathias","repo":"infra"}`))
	require.Error(t, err)
	assert.True(t, errors.Is(err, gitea.ErrValidation))
}

func TestCodeSearchFanOutHappyPath(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		switch r.URL.Path {
		case "/api/v1/users/mathias/repos":
			_, _ = w.Write([]byte(`[
				{"name":"infra","full_name":"mathias/infra","default_branch":"main"},
				{"name":"gitea-mcp","full_name":"mathias/gitea-mcp","default_branch":"main"}
			]`))
		case "/api/v1/repos/mathias/infra/search":
			_, _ = w.Write([]byte(`{"data":[{"path":"main.go","snippet":"infra hit","html_url":"http://x/infra/main.go","score":2.0}],"ok":true}`))
		case "/api/v1/repos/mathias/gitea-mcp/search":
			_, _ = w.Write([]byte(`{"data":[{"path":"cmd/main.go","snippet":"gitea-mcp hit","html_url":"http://x/gitea-mcp/main.go","score":1.0}],"ok":true}`))
		default:
			http.NotFound(w, r)
		}
	}))
	defer srv.Close()

	tool := tools.NewCodeSearch(gitea.NewClient(srv.URL, "tok"), allowlist.New([]string{"mathias"}))
	out, err := tool.Call(context.Background(), json.RawMessage(`{"q":"hit","owner":"mathias"}`))
	require.NoError(t, err)

	var result struct {
		Results []struct {
			Repo    string `json:"repo"`
			Path    string `json:"path"`
			Snippet string `json:"snippet"`
		} `json:"results"`
		Partial bool `json:"partial"`
	}
	require.NoError(t, json.Unmarshal(out, &result))
	assert.False(t, result.Partial)
	require.Len(t, result.Results, 2)

	repos := make([]string, 0, 2)
	for _, r := range result.Results {
		repos = append(repos, r.Repo)
	}
	assert.Contains(t, repos, "mathias/infra")
	assert.Contains(t, repos, "mathias/gitea-mcp")
}

func TestCodeSearchFanOutPartialFailure(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		switch r.URL.Path {
		case "/api/v1/users/mathias/repos":
			_, _ = w.Write([]byte(`[
				{"name":"infra","full_name":"mathias/infra","default_branch":"main"},
				{"name":"broken","full_name":"mathias/broken","default_branch":"main"}
			]`))
		case "/api/v1/repos/mathias/infra/search":
			_, _ = w.Write([]byte(`{"data":[{"path":"main.go","snippet":"infra hit","html_url":"http://x/infra/main.go","score":1.0}],"ok":true}`))
		case "/api/v1/repos/mathias/broken/search":
			w.WriteHeader(http.StatusInternalServerError)
			_, _ = w.Write([]byte(`{"message":"internal error"}`))
		default:
			http.NotFound(w, r)
		}
	}))
	defer srv.Close()

	tool := tools.NewCodeSearch(gitea.NewClient(srv.URL, "tok"), allowlist.New([]string{"mathias"}))
	out, err := tool.Call(context.Background(), json.RawMessage(`{"q":"hit","owner":"mathias"}`))
	require.NoError(t, err)

	var result struct {
		Results      []struct{ Repo string `json:"repo"` } `json:"results"`
		Partial      bool                                  `json:"partial"`
		PartialRepos []string                              `json:"partial_repos"`
	}
	require.NoError(t, json.Unmarshal(out, &result))
	assert.True(t, result.Partial)
	require.Len(t, result.PartialRepos, 1)
	assert.Equal(t, "mathias/broken", result.PartialRepos[0])
	require.Len(t, result.Results, 1)
	assert.Equal(t, "mathias/infra", result.Results[0].Repo)
}

func TestCodeSearchFanOutSortsByScore(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		switch r.URL.Path {
		case "/api/v1/users/mathias/repos":
			_, _ = w.Write([]byte(`[
				{"name":"alpha","full_name":"mathias/alpha","default_branch":"main"},
				{"name":"beta","full_name":"mathias/beta","default_branch":"main"}
			]`))
		case "/api/v1/repos/mathias/alpha/search":
			// low score
			_, _ = w.Write([]byte(`{"data":[{"path":"a.go","snippet":"low","html_url":"http://x/alpha/a.go","score":1.0}],"ok":true}`))
		case "/api/v1/repos/mathias/beta/search":
			// high score
			_, _ = w.Write([]byte(`{"data":[{"path":"b.go","snippet":"high","html_url":"http://x/beta/b.go","score":5.0}],"ok":true}`))
		default:
			http.NotFound(w, r)
		}
	}))
	defer srv.Close()

	tool := tools.NewCodeSearch(gitea.NewClient(srv.URL, "tok"), allowlist.New([]string{"mathias"}))
	out, err := tool.Call(context.Background(), json.RawMessage(`{"q":"something","owner":"mathias"}`))
	require.NoError(t, err)

	var result struct {
		Results []struct {
			Snippet string  `json:"snippet"`
			Score   float64 `json:"score"`
		} `json:"results"`
	}
	require.NoError(t, json.Unmarshal(out, &result))
	require.Len(t, result.Results, 2)
	// First result must be the high-score one
	assert.True(t, result.Results[0].Score > result.Results[1].Score,
		"expected results sorted by score desc, got %v then %v",
		result.Results[0].Score, result.Results[1].Score)
	assert.True(t, strings.Contains(result.Results[0].Snippet, "high"))
}