package domain

import (
	"time"
)

// ArtifactRefType defines how an artifact is referenced.
type ArtifactRefType string

const (
	ArtifactRefInline ArtifactRefType = "inline"
	ArtifactRefFile   ArtifactRefType = "file"
)

// OutputFormat defines the desired format of the generated artifact.
type OutputFormat string

const (
	FormatText     OutputFormat = "text"
	FormatMarkdown OutputFormat = "markdown"
	FormatJSON     OutputFormat = "json"
)

// ValidationMode defines how the output should be validated.
type ValidationMode string

const (
	ValidationNone       ValidationMode = "none"
	ValidationBasic      ValidationMode = "basic"
	ValidationJSON       ValidationMode = "json"
	ValidationJSONSchema ValidationMode = "json_schema"
)

// ValidationStatus defines the result of a validation check.
type ValidationStatus string

const (
	ValidationPassed  ValidationStatus = "passed"
	ValidationFailed  ValidationStatus = "failed"
	ValidationSkipped ValidationStatus = "skipped"
)

// CacheControlType defines provider cache behavior for prompt content.
type CacheControlType string

const (
	CacheControlEphemeral CacheControlType = "ephemeral"
)

const (
	// SessionIDMaxLength is OpenRouter's documented maximum session_id length.
	SessionIDMaxLength = 256
)

// CacheControl describes provider cache metadata attached to prompt content.
type CacheControl struct {
	Type CacheControlType `yaml:"type" json:"type"`
	TTL  string           `yaml:"ttl,omitempty" json:"ttl,omitempty"`
}

// RunRequest represents a request to generate a single artifact.
type RunRequest struct {
	PromptID      string
	PromptVersion string
	ProfileID     string
	Inputs        map[string]ArtifactRef
	Vars          map[string]string
	Execution     *ExecutionTargetOverride
	Validation    *OutputContract
	Metadata      map[string]string
}

// RunResult represents the complete result of a prompt execution run.
type RunResult struct {
	RunID                string
	Artifact             Artifact
	RawOutput            string
	Validation           ValidationResult
	PromptID             string
	PromptVersion        string
	PromptHash           string
	RenderedPromptHash   string
	SelectedProfileID    string
	ModelName            string
	Endpoint             string
	EffectiveModelParams ExecutionTarget
	InputHashes          map[string]string
	Usage                TokenUsage
	StartTime            time.Time
	EndTime              time.Time
	Duration             time.Duration
	Error                error
}

// PreparedRun contains pre-LLM execution state from the prepare/render phase.
// It must never include resolved API key values, model output, or validation data.
type PreparedRun struct {
	PromptID             string                  `json:"prompt_id"`
	PromptVersion        string                  `json:"prompt_version,omitempty"`
	PromptHash           string                  `json:"prompt_hash,omitempty"`
	SelectedProfileID    string                  `json:"selected_profile_id"`
	EffectiveModelParams ExecutionTarget         `json:"effective_model_params"`
	TargetPresence       ExecutionTargetPresence `json:"-"`
	OutputContract       OutputContract          `json:"output_contract"`
	StructuredOutput     *StructuredOutputSpec   `json:"structured_output,omitempty"`
	InputHashes          map[string]string       `json:"input_hashes,omitempty"`
	SessionID            string                  `json:"session_id,omitempty"`
	RenderedPromptHash   string                  `json:"rendered_prompt_hash"`
	Messages             []RenderedMessage       `json:"messages"`
	StartTime            time.Time               `json:"start_time,omitempty"`
	EndTime              time.Time               `json:"end_time,omitempty"`
	DurationMS           int64                   `json:"duration_ms,omitempty"`
}

// ArtifactRef represents a reference to an input artifact.
type ArtifactRef struct {
	Type ArtifactRefType
	URI  string
	Body string // Used for inline
}

// Artifact represents the actual loaded content of a reference.
type Artifact struct {
	Name        string
	ContentType string
	Body        []byte
	URI         string
	Size        int64
	Hash        string
}

// PromptDefinition represents a configured prompt execution definition.
type PromptDefinition struct {
	ID             string                  `yaml:"id"`
	Version        string                  `yaml:"version"`
	DefaultProfile string                  `yaml:"default_profile"`
	Description    string                  `yaml:"description"`
	SessionID      string                  `yaml:"session_id" json:"session_id,omitempty"`
	Inputs         []PromptInput           `yaml:"inputs"`
	Templates      []PromptMessageTemplate `yaml:"templates"`
	OutputFormat   OutputFormat            `yaml:"output_format"`
	Validation     OutputContract          `yaml:"validation"`
}

// PromptInput describes one named input expected by a prompt definition.
type PromptInput struct {
	Name        string `yaml:"name"`
	Required    bool   `yaml:"required"`
	ContentType string `yaml:"content_type"`
	Description string `yaml:"description"`
}

// PromptMessageTemplate defines a template for a chat message.
type PromptMessageTemplate struct {
	Role         string        `yaml:"role"`
	Content      string        `yaml:"content"`
	ContentFile  string        `yaml:"content_file"`
	CacheControl *CacheControl `yaml:"cache_control,omitempty" json:"cache_control,omitempty"`
}

// ExecutionProfile describes how and where to execute a model.
type ExecutionProfile struct {
	ID              string         `yaml:"id"`
	Endpoint        string         `yaml:"endpoint"`
	Model           string         `yaml:"model"`
	Temperature     float64        `yaml:"temperature"`
	MaxTokens       int            `yaml:"max_tokens"`
	TopP            float64        `yaml:"top_p"`
	TimeoutSeconds  int            `yaml:"timeout_seconds"`
	ServiceTier     string         `yaml:"service_tier"`
	ReasoningEffort string         `yaml:"reasoning_effort"`
	APIKeyEnv       string         `yaml:"api_key_env"`
	ExtraParams     map[string]any `yaml:"extra_params"`
}

// ExecutionTargetOverride represents per-request runtime setting overrides.
type ExecutionTargetOverride struct {
	Endpoint        string         `json:"endpoint,omitempty"`
	Model           string         `json:"model,omitempty"`
	Temperature     *float64       `json:"temperature,omitempty"`
	MaxTokens       *int           `json:"max_tokens,omitempty"`
	TopP            *float64       `json:"top_p,omitempty"`
	TimeoutSeconds  *int           `json:"timeout_seconds,omitempty"`
	ServiceTier     string         `json:"service_tier,omitempty"`
	ReasoningEffort string         `json:"reasoning_effort,omitempty"`
	APIKeyEnv       string         `json:"api_key_env,omitempty"`
	ExtraParams     map[string]any `json:"extra_params,omitempty"`
}

// ExecutionTargetPresence tracks which effective runtime fields came from an
// explicit request override even when the resolved value is a zero value.
type ExecutionTargetPresence struct {
	Temperature    bool
	MaxTokens      bool
	TopP           bool
	TimeoutSeconds bool
}

// ExecutionTarget represents effective model runtime settings for a run.
type ExecutionTarget struct {
	Endpoint        string         `yaml:"endpoint" json:"endpoint"`
	Model           string         `yaml:"model" json:"model"`
	Temperature     float64        `yaml:"temperature" json:"temperature"`
	MaxTokens       int            `yaml:"max_tokens" json:"max_tokens"`
	TopP            float64        `yaml:"top_p" json:"top_p"`
	TimeoutSeconds  int            `yaml:"timeout_seconds" json:"timeout_seconds"`
	ServiceTier     string         `yaml:"service_tier" json:"service_tier"`
	ReasoningEffort string         `yaml:"reasoning_effort" json:"reasoning_effort"`
	APIKeyEnv       string         `yaml:"api_key_env" json:"api_key_env"`
	ExtraParams     map[string]any `yaml:"extra_params" json:"extra_params"`
}

// OutputContract defines the requirements for the output artifact.
type OutputContract struct {
	Format         OutputFormat   `yaml:"format"`
	ValidationMode ValidationMode `yaml:"validation_mode"`
	SchemaPath     string         `yaml:"schema_path"`
	RepairAttempts int            `yaml:"repair_attempts"`
}

// RenderedPrompt represents the prompt after template application.
type RenderedPrompt struct {
	SessionID string            `json:"session_id,omitempty"`
	Messages  []RenderedMessage `json:"messages"`
}

// RenderedMessage is a single message in a rendered prompt.
type RenderedMessage struct {
	Role         string        `json:"role"`
	Content      string        `json:"content"`
	CacheControl *CacheControl `json:"cache_control,omitempty"`
}

// GenerateRequest is the internal request passed to the LLM client.
type GenerateRequest struct {
	Prompt           RenderedPrompt
	Target           ExecutionTarget
	TargetPresence   ExecutionTargetPresence
	StructuredOutput *StructuredOutputSpec
}

// StructuredOutputType indicates which provider-level output mode is requested.
type StructuredOutputType string

const (
	StructuredOutputJSONSchema StructuredOutputType = "json_schema"
)

// StructuredOutputSpec describes provider-level structured output requirements.
type StructuredOutputSpec struct {
	Type       StructuredOutputType      `json:"type"`
	JSONSchema *StructuredOutputJSONSpec `json:"json_schema,omitempty"`
}

// StructuredOutputJSONSpec contains json_schema output constraints.
type StructuredOutputJSONSpec struct {
	Name   string `json:"name"`
	Strict bool   `json:"strict"`
	Schema any    `json:"schema"`
}

// GenerateResponse is the response received from the LLM client.
type GenerateResponse struct {
	Content string
	Usage   TokenUsage
}

// TokenUsage tracks token consumption.
type TokenUsage struct {
	PromptTokens     int
	CompletionTokens int
	TotalTokens      int
	CachedTokens     int
	CacheWriteTokens int
}

// ValidationResult represents the outcome of an output validation.
type ValidationResult struct {
	Status         ValidationStatus
	Mode           ValidationMode
	Errors         []string
	SchemaPath     string
	RepairAttempts int
	IsValid        bool
}

// RunMetadata contains auditing information for a run.
type RunMetadata struct {
	RunID              string
	PromptID           string
	PromptVersion      string
	PromptHash         string
	RenderedPromptHash string
	SelectedProfileID  string
	InputHashes        map[string]string
	ModelEndpoint      string
	ModelName          string
	Params             ExecutionTarget
	Timestamp          time.Time
	Duration           time.Duration
	Usage              TokenUsage
	ValidationMode     ValidationMode
	ValidationStatus   ValidationStatus
	RepairAttempts     int
}