package sessionread

import (
	"errors"
	"strings"
	"testing"

	"git.yeij.top/AskaEth/Cyrene_v2/internal/capability/registry"
	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/history"
	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/tool"
)

// mainFake is the fixture the dispatcher-level tests read through: an existing main
// session carrying two messages.
func mainFake() *fakeHistory {
	return &fakeHistory{
		sessions: []history.SessionMeta{{ID: history.MainSessionID, Title: "调试日志"}},
		msgs: map[string][]history.Message{history.MainSessionID: {
			{SessionID: history.MainSessionID, Role: history.RoleAssistant, Content: "在的", PersonaID: "yuki", CreatedAt: at(21, 7)},
			{SessionID: history.MainSessionID, Role: history.RoleUser, Content: "你好", CreatedAt: at(21, 4)},
		}},
	}
}

// TestNameIsSessionRead locks the registered tool name design/22 §8.1 fixes.
func TestNameIsSessionRead(t *testing.T) {
	t.Parallel()
	if got := New().Name(); got != "session_read" {
		t.Fatalf("Name() = %q, want session_read", got)
	}
}

// TestParametersSchema locks the argument contract: sessionId is required, limit and
// before are optional numbers, and limit deliberately declares no maximum — a value
// above the cap must be clamped by the tool rather than rejected by the validator as
// a malformed call.
func TestParametersSchema(t *testing.T) {
	t.Parallel()
	params, err := New().Parameters()
	if err != nil {
		t.Fatalf("Parameters: %v", err)
	}
	if params["type"] != "object" {
		t.Fatalf("schema type = %v, want object", params["type"])
	}
	required, ok := params["required"].([]any)
	if !ok || len(required) != 1 || required[0] != "sessionId" {
		t.Fatalf("required = %#v, want [sessionId]", params["required"])
	}
	props, ok := params["properties"].(map[string]any)
	if !ok {
		t.Fatalf("properties = %#v, want an object", params["properties"])
	}
	for _, name := range []string{"sessionId", "limit", "before"} {
		prop, ok := props[name].(map[string]any)
		if !ok {
			t.Fatalf("property %q missing from the schema", name)
		}
		if desc, _ := prop["description"].(string); strings.TrimSpace(desc) == "" {
			t.Fatalf("property %q has no description; the model cannot use it", name)
		}
	}
	if limit := props["limit"].(map[string]any); limit["type"] != "integer" {
		t.Fatalf("limit type = %v, want integer", limit["type"])
	} else if _, bounded := limit["maximum"]; bounded {
		t.Fatal("limit declares a maximum; an over-cap value must be clamped, not rejected")
	}
	if before := props["before"].(map[string]any); before["type"] != "integer" {
		t.Fatalf("before type = %v, want integer", before["type"])
	}
}

// TestDescriptionMarksTheMaterialAsExternal locks the wording the model sees: it has
// to say the result is a read-only transcript of SOMEBODY ELSE's session, because
// that label is what keeps her from quoting it as her own memory (design/22 §8-3).
func TestDescriptionMarksTheMaterialAsExternal(t *testing.T) {
	t.Parallel()
	desc := New().Description()
	for _, want := range []string{"read-only", "your own memory", "web:<uuid>"} {
		if !strings.Contains(desc, want) {
			t.Fatalf("Description() = %q, want it to mention %q", desc, want)
		}
	}
}

// TestDispatcherInvokesTheTool drives the tool through the real dispatcher, which
// validates the arguments against Parameters() and coerces a decoded-JSON number
// (float64) to the schema's integer. It is the closest thing to the model's own
// call path that a unit test can exercise.
func TestDispatcherInvokesTheTool(t *testing.T) {
	t.Parallel()
	reg := registry.New()
	d, err := tool.New(reg)
	if err != nil {
		t.Fatalf("tool.New: %v", err)
	}
	if err := d.Register(newReader(mainFake(), testPersonas())); err != nil {
		t.Fatalf("register: %v", err)
	}
	out, err := d.Invoke(ownerCtx(), ToolName, map[string]any{"sessionId": "web", "limit": float64(1)})
	if err != nil {
		t.Fatalf("Invoke: %v", err)
	}
	text, ok := out.(string)
	if !ok {
		t.Fatalf("Invoke returned %T, want a string material", out)
	}
	if !strings.Contains(text, "在的") || strings.Contains(text, "你好") {
		t.Fatalf("material = %q, want only the newest message (limit 1 via float64)", text)
	}
}

// TestDispatcherRejectsNoSessionID asserts the schema's required field is enforced
// before Execute, so a target-less call never reaches the reader.
func TestDispatcherRejectsNoSessionID(t *testing.T) {
	t.Parallel()
	reg := registry.New()
	d, err := tool.New(reg)
	if err != nil {
		t.Fatalf("tool.New: %v", err)
	}
	h := mainFake()
	if err := d.Register(newReader(h, testPersonas())); err != nil {
		t.Fatalf("register: %v", err)
	}
	if _, err := d.Invoke(ownerCtx(), ToolName, map[string]any{}); !errors.Is(err, tool.ErrInvalidArgs) {
		t.Fatalf("err = %v, want ErrInvalidArgs", err)
	}
	if h.listCalls != 0 {
		t.Fatalf("history was read %d times for a target-less call, want 0", h.listCalls)
	}
}