1package provider
2
3import (
4 "context"
5 "fmt"
6 "strings"
7 "sync"
8)
9
10const (
11 // APICompletions identifies the OpenAI Chat Completions wire API.
12 APICompletions = "openai-completions"
13 // APIResponses identifies the OpenAI Responses wire API.
14 APIResponses = "openai-responses"
15 // APIAnthropicMessages identifies the Anthropic Messages wire API.
16 APIAnthropicMessages = "anthropic-messages"
17)
18
19// modelRouter dispatches each request according to the selected model's API.
20// This lets one provider expose models that use different wire protocols while
21// remaining reusable across model switches.
22type modelRouter struct {
23 name string
24 fallback Client
25 byAPI map[string]Client
26 modelOverridesMu sync.RWMutex
27 modelOverrides map[string]Model
28 dynamicCatalog bool
29 scopedCatalog bool
30}
31
32// ModelMetadataSetter lets a runtime-owned client retain model metadata
33// without consulting the process-global catalog on every request.
34type ModelMetadataSetter interface {
35 SetModelMetadata(Model)
36}
37
38// NewModelRouter creates a client that dispatches requests using Model.API.
39// Models with no API override, and models absent from the catalog, use fallback;
40// an explicit API without a registered client returns an error.
41func NewModelRouter(name string, fallback Client, byAPI map[string]Client) Client {
42 return &modelRouter{name: name, fallback: fallback, byAPI: byAPI}
43}
44
45func (c *modelRouter) Name() string { return c.name }
46
47func (c *modelRouter) SetModelMetadata(model Model) {
48 model = cloneModel(model)
49 c.modelOverridesMu.Lock()
50 if c.modelOverrides == nil {
51 c.modelOverrides = make(map[string]Model)
52 }
53 c.modelOverrides[model.ID] = model
54 c.modelOverridesMu.Unlock()
55
56 setModelMetadata(c.fallback, model)
57 for _, client := range c.byAPI {
58 setModelMetadata(client, model)
59 }
60}
61
62func (c *modelRouter) modelOverride(id string) (Model, bool) {
63 c.modelOverridesMu.RLock()
64 model, ok := c.modelOverrides[id]
65 if ok {
66 model = cloneModel(model)
67 }
68 c.modelOverridesMu.RUnlock()
69 return model, ok
70}
71
72func setModelMetadata(client Client, model Model) {
73 if setter, ok := client.(ModelMetadataSetter); ok {
74 setter.SetModelMetadata(model)
75 }
76}
77
78func (c *modelRouter) Stream(ctx context.Context, req Request) (<-chan Event, error) {
79 req.Model = strings.TrimSpace(req.Model)
80 if err := ValidateFastMode(c.Name(), req.FastMode); err != nil {
81 return nil, err
82 }
83 client := c.fallback
84 api := ""
85 found := false
86 if c.dynamicCatalog {
87 // Normal CLI/RPC runtimes follow the process-global catalog so a
88 // background refresh can replace stale request metadata. Keep a
89 // bootstrap override only until an authoritative live entry exists.
90 if model, err := FindModel(c.name, req.Model); err == nil {
91 api = model.API
92 found = true
93 c.SetModelMetadata(model)
94 } else if !IsProviderCatalogAuthoritative(c.name) {
95 if model, ok := c.modelOverride(req.Model); ok {
96 api = model.API
97 found = true
98 }
99 }
100 } else if model, ok := c.modelOverride(req.Model); ok {
101 api = model.API
102 found = true
103 } else if !c.scopedCatalog {
104 if model, err := FindModel(c.name, req.Model); err == nil {
105 api = model.API
106 found = true
107 }
108 }
109 if !found && c.dynamicCatalog && IsProviderCatalogAuthoritative(c.name) {
110 return nil, fmt.Errorf("unknown model %q (provider=%q)", req.Model, c.name)
111 }
112 if api == "" && !c.scopedCatalog && AcceptsUnlistedModels(c.name) {
113 // The OpenCode Go catalog is intentionally live-only. Preserve the
114 // family route for an explicit model while the first discovery is
115 // still in flight or unavailable.
116 api = openCodeGoAPIForModel(req.Model)
117 }
118 if api != "" {
119 routed := c.byAPI[api]
120 if routed == nil && api == APICompletions {
121 routed = c.fallback
122 }
123 if routed == nil {
124 return nil, fmt.Errorf("provider %q model %q requests unsupported wire API %q", c.name, req.Model, api)
125 }
126 client = routed
127 }
128 return client.Stream(ctx, req)
129}