first commit

internal/db/db.go

@@ -0,0 +1,31 @@
+// Code generated by sqlc. DO NOT EDIT.
+// versions:
+//   sqlc v1.30.0
+
+package db
+
+import (
+    "context"
+    "database/sql"
+)
+
+type DBTX interface {
+    ExecContext(context.Context, string, ...interface{}) (sql.Result, error)
+    PrepareContext(context.Context, string) (*sql.Stmt, error)
+    QueryContext(context.Context, string, ...interface{}) (*sql.Rows, error)
+    QueryRowContext(context.Context, string, ...interface{}) *sql.Row
+}
+
+func New(db DBTX) *Queries {
+    return &Queries{db: db}
+}
+
+type Queries struct {
+    db DBTX
+}
+
+func (q *Queries) WithTx(tx *sql.Tx) *Queries {
+    return &Queries{
+        db: tx,
+    }
+}

internal/db/migrations/001_init.sql

@@ -0,0 +1,58 @@
+-- Sessions table: replaces noted CLI dependency for session persistence.
+CREATE TABLE IF NOT EXISTS sessions (
+    id         INTEGER PRIMARY KEY AUTOINCREMENT,
+    title      TEXT    NOT NULL DEFAULT '',
+    model      TEXT    NOT NULL DEFAULT '',
+    mode       TEXT    NOT NULL DEFAULT 'BUILD',
+    created_at TEXT    NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now')),
+    updated_at TEXT    NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now'))
+);
+
+-- Session messages: individual chat entries within a session.
+CREATE TABLE IF NOT EXISTS session_messages (
+    id         INTEGER PRIMARY KEY AUTOINCREMENT,
+    session_id INTEGER NOT NULL REFERENCES sessions(id) ON DELETE CASCADE,
+    role       TEXT    NOT NULL, -- 'user', 'assistant', 'tool', 'system', 'error'
+    content    TEXT    NOT NULL DEFAULT '',
+    tool_name  TEXT    NOT NULL DEFAULT '',
+    tool_args  TEXT    NOT NULL DEFAULT '',
+    is_error   INTEGER NOT NULL DEFAULT 0,
+    thinking   TEXT    NOT NULL DEFAULT '',
+    created_at TEXT    NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now'))
+);
+
+CREATE INDEX IF NOT EXISTS idx_session_messages_session_id ON session_messages(session_id);
+
+-- Tool permissions: per-tool allow/deny/always-allow.
+CREATE TABLE IF NOT EXISTS tool_permissions (
+    id         INTEGER PRIMARY KEY AUTOINCREMENT,
+    tool_name  TEXT    NOT NULL UNIQUE,
+    policy     TEXT    NOT NULL DEFAULT 'ask', -- 'allow', 'deny', 'ask'
+    updated_at TEXT    NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now'))
+);
+
+-- Token usage stats: per-turn tracking.
+CREATE TABLE IF NOT EXISTS token_stats (
+    id            INTEGER PRIMARY KEY AUTOINCREMENT,
+    session_id    INTEGER NOT NULL REFERENCES sessions(id) ON DELETE CASCADE,
+    turn          INTEGER NOT NULL DEFAULT 0,
+    eval_count    INTEGER NOT NULL DEFAULT 0,
+    prompt_tokens INTEGER NOT NULL DEFAULT 0,
+    model         TEXT    NOT NULL DEFAULT '',
+    created_at    TEXT    NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now'))
+);
+
+CREATE INDEX IF NOT EXISTS idx_token_stats_session_id ON token_stats(session_id);
+
+-- File changes: files modified by agent during a session.
+CREATE TABLE IF NOT EXISTS file_changes (
+    id         INTEGER PRIMARY KEY AUTOINCREMENT,
+    session_id INTEGER NOT NULL REFERENCES sessions(id) ON DELETE CASCADE,
+    file_path  TEXT    NOT NULL,
+    tool_name  TEXT    NOT NULL DEFAULT '',
+    added      INTEGER NOT NULL DEFAULT 0,
+    removed    INTEGER NOT NULL DEFAULT 0,
+    created_at TEXT    NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ', 'now'))
+);
+
+CREATE INDEX IF NOT EXISTS idx_file_changes_session_id ON file_changes(session_id);

internal/db/models.go

@@ -0,0 +1,53 @@
+// Code generated by sqlc. DO NOT EDIT.
+// versions:
+//   sqlc v1.30.0
+
+package db
+
+type FileChange struct {
+    ID        int64  `json:"id"`
+    SessionID int64  `json:"session_id"`
+    FilePath  string `json:"file_path"`
+    ToolName  string `json:"tool_name"`
+    Added     int64  `json:"added"`
+    Removed   int64  `json:"removed"`
+    CreatedAt string `json:"created_at"`
+}
+
+type Session struct {
+    ID        int64  `json:"id"`
+    Title     string `json:"title"`
+    Model     string `json:"model"`
+    Mode      string `json:"mode"`
+    CreatedAt string `json:"created_at"`
+    UpdatedAt string `json:"updated_at"`
+}
+
+type SessionMessage struct {
+    ID        int64  `json:"id"`
+    SessionID int64  `json:"session_id"`
+    Role      string `json:"role"`
+    Content   string `json:"content"`
+    ToolName  string `json:"tool_name"`
+    ToolArgs  string `json:"tool_args"`
+    IsError   int64  `json:"is_error"`
+    Thinking  string `json:"thinking"`
+    CreatedAt string `json:"created_at"`
+}
+
+type TokenStat struct {
+    ID           int64  `json:"id"`
+    SessionID    int64  `json:"session_id"`
+    Turn         int64  `json:"turn"`
+    EvalCount    int64  `json:"eval_count"`
+    PromptTokens int64  `json:"prompt_tokens"`
+    Model        string `json:"model"`
+    CreatedAt    string `json:"created_at"`
+}
+
+type ToolPermission struct {
+    ID        int64  `json:"id"`
+    ToolName  string `json:"tool_name"`
+    Policy    string `json:"policy"`
+    UpdatedAt string `json:"updated_at"`
+}

internal/db/permissions.sql.go

@@ -0,0 +1,100 @@
+// Code generated by sqlc. DO NOT EDIT.
+// versions:
+//   sqlc v1.30.0
+// source: permissions.sql
+
+package db
+
+import (
+    "context"
+)
+
+const deleteToolPermission = `-- name: DeleteToolPermission :exec
+DELETE FROM tool_permissions WHERE tool_name = ?
+`
+
+func (q *Queries) DeleteToolPermission(ctx context.Context, toolName string) error {
+    _, err := q.db.ExecContext(ctx, deleteToolPermission, toolName)
+    return err
+}
+
+const getToolPermission = `-- name: GetToolPermission :one
+SELECT id, tool_name, policy, updated_at FROM tool_permissions WHERE tool_name = ?
+`
+
+func (q *Queries) GetToolPermission(ctx context.Context, toolName string) (ToolPermission, error) {
+    row := q.db.QueryRowContext(ctx, getToolPermission, toolName)
+    var i ToolPermission
+    err := row.Scan(
+        &i.ID,
+        &i.ToolName,
+        &i.Policy,
+        &i.UpdatedAt,
+    )
+    return i, err
+}
+
+const listToolPermissions = `-- name: ListToolPermissions :many
+SELECT id, tool_name, policy, updated_at FROM tool_permissions ORDER BY tool_name ASC
+`
+
+func (q *Queries) ListToolPermissions(ctx context.Context) ([]ToolPermission, error) {
+    rows, err := q.db.QueryContext(ctx, listToolPermissions)
+    if err != nil {
+        return nil, err
+    }
+    defer rows.Close()
+    items := []ToolPermission{}
+    for rows.Next() {
+        var i ToolPermission
+        if err := rows.Scan(
+            &i.ID,
+            &i.ToolName,
+            &i.Policy,
+            &i.UpdatedAt,
+        ); err != nil {
+            return nil, err
+        }
+        items = append(items, i)
+    }
+    if err := rows.Close(); err != nil {
+        return nil, err
+    }
+    if err := rows.Err(); err != nil {
+        return nil, err
+    }
+    return items, nil
+}
+
+const resetToolPermissions = `-- name: ResetToolPermissions :exec
+DELETE FROM tool_permissions
+`
+
+func (q *Queries) ResetToolPermissions(ctx context.Context) error {
+    _, err := q.db.ExecContext(ctx, resetToolPermissions)
+    return err
+}
+
+const upsertToolPermission = `-- name: UpsertToolPermission :one
+INSERT INTO tool_permissions (tool_name, policy)
+VALUES (?, ?)
+ON CONFLICT(tool_name) DO UPDATE SET policy = excluded.policy, updated_at = strftime('%Y-%m-%dT%H:%M:%fZ', 'now')
+RETURNING id, tool_name, policy, updated_at
+`
+
+type UpsertToolPermissionParams struct {
+    ToolName string `json:"tool_name"`
+    Policy   string `json:"policy"`
+}
+
+func (q *Queries) UpsertToolPermission(ctx context.Context, arg UpsertToolPermissionParams) (ToolPermission, error) {
+    row := q.db.QueryRowContext(ctx, upsertToolPermission, arg.ToolName, arg.Policy)
+    var i ToolPermission
+    err := row.Scan(
+        &i.ID,
+        &i.ToolName,
+        &i.Policy,
+        &i.UpdatedAt,
+    )
+    return i, err
+}

internal/db/queries/permissions.sql

@@ -0,0 +1,17 @@
+-- name: GetToolPermission :one
+SELECT * FROM tool_permissions WHERE tool_name = ?;
+
+-- name: UpsertToolPermission :one
+INSERT INTO tool_permissions (tool_name, policy)
+VALUES (?, ?)
+ON CONFLICT(tool_name) DO UPDATE SET policy = excluded.policy, updated_at = strftime('%Y-%m-%dT%H:%M:%fZ', 'now')
+RETURNING *;
+
+-- name: ListToolPermissions :many
+SELECT * FROM tool_permissions ORDER BY tool_name ASC;
+
+-- name: DeleteToolPermission :exec
+DELETE FROM tool_permissions WHERE tool_name = ?;
+
+-- name: ResetToolPermissions :exec
+DELETE FROM tool_permissions;

internal/db/queries/sessions.sql

@@ -0,0 +1,27 @@
+-- name: CreateSession :one
+INSERT INTO sessions (title, model, mode) VALUES (?, ?, ?) RETURNING *;
+
+-- name: GetSession :one
+SELECT * FROM sessions WHERE id = ?;
+
+-- name: ListSessions :many
+SELECT * FROM sessions ORDER BY updated_at DESC LIMIT ?;
+
+-- name: UpdateSessionTitle :exec
+UPDATE sessions SET title = ?, updated_at = strftime('%Y-%m-%dT%H:%M:%fZ', 'now') WHERE id = ?;
+
+-- name: UpdateSessionTimestamp :exec
+UPDATE sessions SET updated_at = strftime('%Y-%m-%dT%H:%M:%fZ', 'now') WHERE id = ?;
+
+-- name: DeleteSession :exec
+DELETE FROM sessions WHERE id = ?;
+
+-- name: CreateSessionMessage :one
+INSERT INTO session_messages (session_id, role, content, tool_name, tool_args, is_error, thinking)
+VALUES (?, ?, ?, ?, ?, ?, ?) RETURNING *;
+
+-- name: GetSessionMessages :many
+SELECT * FROM session_messages WHERE session_id = ? ORDER BY id ASC;
+
+-- name: CountSessions :one
+SELECT COUNT(*) FROM sessions;

internal/db/queries/stats.sql

@@ -0,0 +1,31 @@
+-- name: RecordTokenUsage :one
+INSERT INTO token_stats (session_id, turn, eval_count, prompt_tokens, model)
+VALUES (?, ?, ?, ?, ?) RETURNING *;
+
+-- name: GetSessionTokenStats :many
+SELECT * FROM token_stats WHERE session_id = ? ORDER BY turn ASC;
+
+-- name: GetSessionTotalTokens :one
+SELECT
+    CAST(COALESCE(SUM(eval_count), 0) AS INTEGER) AS total_eval,
+    CAST(COALESCE(SUM(prompt_tokens), 0) AS INTEGER) AS total_prompt,
+    CAST(COUNT(*) AS INTEGER) AS turn_count
+FROM token_stats WHERE session_id = ?;
+
+-- name: RecordFileChange :one
+INSERT INTO file_changes (session_id, file_path, tool_name, added, removed)
+VALUES (?, ?, ?, ?, ?) RETURNING *;
+
+-- name: GetSessionFileChanges :many
+SELECT * FROM file_changes WHERE session_id = ? ORDER BY created_at ASC;
+
+-- name: GetSessionFileChangeSummary :many
+SELECT
+    file_path,
+    CAST(COALESCE(SUM(added), 0) AS INTEGER) AS total_added,
+    CAST(COALESCE(SUM(removed), 0) AS INTEGER) AS total_removed,
+    CAST(COUNT(*) AS INTEGER) AS change_count
+FROM file_changes
+WHERE session_id = ?
+GROUP BY file_path
+ORDER BY file_path ASC;

internal/db/sessions.sql.go

@@ -0,0 +1,206 @@
+// Code generated by sqlc. DO NOT EDIT.
+// versions:
+//   sqlc v1.30.0
+// source: sessions.sql
+
+package db
+
+import (
+    "context"
+)
+
+const countSessions = `-- name: CountSessions :one
+SELECT COUNT(*) FROM sessions
+`
+
+func (q *Queries) CountSessions(ctx context.Context) (int64, error) {
+    row := q.db.QueryRowContext(ctx, countSessions)
+    var count int64
+    err := row.Scan(&count)
+    return count, err
+}
+
+const createSession = `-- name: CreateSession :one
+INSERT INTO sessions (title, model, mode) VALUES (?, ?, ?) RETURNING id, title, model, mode, created_at, updated_at
+`
+
+type CreateSessionParams struct {
+    Title string `json:"title"`
+    Model string `json:"model"`
+    Mode  string `json:"mode"`
+}
+
+func (q *Queries) CreateSession(ctx context.Context, arg CreateSessionParams) (Session, error) {
+    row := q.db.QueryRowContext(ctx, createSession, arg.Title, arg.Model, arg.Mode)
+    var i Session
+    err := row.Scan(
+        &i.ID,
+        &i.Title,
+        &i.Model,
+        &i.Mode,
+        &i.CreatedAt,
+        &i.UpdatedAt,
+    )
+    return i, err
+}
+
+const createSessionMessage = `-- name: CreateSessionMessage :one
+INSERT INTO session_messages (session_id, role, content, tool_name, tool_args, is_error, thinking)
+VALUES (?, ?, ?, ?, ?, ?, ?) RETURNING id, session_id, role, content, tool_name, tool_args, is_error, thinking, created_at
+`
+
+type CreateSessionMessageParams struct {
+    SessionID int64  `json:"session_id"`
+    Role      string `json:"role"`
+    Content   string `json:"content"`
+    ToolName  string `json:"tool_name"`
+    ToolArgs  string `json:"tool_args"`
+    IsError   int64  `json:"is_error"`
+    Thinking  string `json:"thinking"`
+}
+
+func (q *Queries) CreateSessionMessage(ctx context.Context, arg CreateSessionMessageParams) (SessionMessage, error) {
+    row := q.db.QueryRowContext(ctx, createSessionMessage,
+        arg.SessionID,
+        arg.Role,
+        arg.Content,
+        arg.ToolName,
+        arg.ToolArgs,
+        arg.IsError,
+        arg.Thinking,
+    )
+    var i SessionMessage
+    err := row.Scan(
+        &i.ID,
+        &i.SessionID,
+        &i.Role,
+        &i.Content,
+        &i.ToolName,
+        &i.ToolArgs,
+        &i.IsError,
+        &i.Thinking,
+        &i.CreatedAt,
+    )
+    return i, err
+}
+
+const deleteSession = `-- name: DeleteSession :exec
+DELETE FROM sessions WHERE id = ?
+`
+
+func (q *Queries) DeleteSession(ctx context.Context, id int64) error {
+    _, err := q.db.ExecContext(ctx, deleteSession, id)
+    return err
+}
+
+const getSession = `-- name: GetSession :one
+SELECT id, title, model, mode, created_at, updated_at FROM sessions WHERE id = ?
+`
+
+func (q *Queries) GetSession(ctx context.Context, id int64) (Session, error) {
+    row := q.db.QueryRowContext(ctx, getSession, id)
+    var i Session
+    err := row.Scan(
+        &i.ID,
+        &i.Title,
+        &i.Model,
+        &i.Mode,
+        &i.CreatedAt,
+        &i.UpdatedAt,
+    )
+    return i, err
+}
+
+const getSessionMessages = `-- name: GetSessionMessages :many
+SELECT id, session_id, role, content, tool_name, tool_args, is_error, thinking, created_at FROM session_messages WHERE session_id = ? ORDER BY id ASC
+`
+
+func (q *Queries) GetSessionMessages(ctx context.Context, sessionID int64) ([]SessionMessage, error) {
+    rows, err := q.db.QueryContext(ctx, getSessionMessages, sessionID)
+    if err != nil {
+        return nil, err
+    }
+    defer rows.Close()
+    items := []SessionMessage{}
+    for rows.Next() {
+        var i SessionMessage
+        if err := rows.Scan(
+            &i.ID,
+            &i.SessionID,
+            &i.Role,
+            &i.Content,
+            &i.ToolName,
+            &i.ToolArgs,
+            &i.IsError,
+            &i.Thinking,
+            &i.CreatedAt,
+        ); err != nil {
+            return nil, err
+        }
+        items = append(items, i)
+    }
+    if err := rows.Close(); err != nil {
+        return nil, err
+    }
+    if err := rows.Err(); err != nil {
+        return nil, err
+    }
+    return items, nil
+}
+
+const listSessions = `-- name: ListSessions :many
+SELECT id, title, model, mode, created_at, updated_at FROM sessions ORDER BY updated_at DESC LIMIT ?
+`
+
+func (q *Queries) ListSessions(ctx context.Context, limit int64) ([]Session, error) {
+    rows, err := q.db.QueryContext(ctx, listSessions, limit)
+    if err != nil {
+        return nil, err
+    }
+    defer rows.Close()
+    items := []Session{}
+    for rows.Next() {
+        var i Session
+        if err := rows.Scan(
+            &i.ID,
+            &i.Title,
+            &i.Model,
+            &i.Mode,
+            &i.CreatedAt,
+            &i.UpdatedAt,
+        ); err != nil {
+            return nil, err
+        }
+        items = append(items, i)
+    }
+    if err := rows.Close(); err != nil {
+        return nil, err
+    }
+    if err := rows.Err(); err != nil {
+        return nil, err
+    }
+    return items, nil
+}
+
+const updateSessionTimestamp = `-- name: UpdateSessionTimestamp :exec
+UPDATE sessions SET updated_at = strftime('%Y-%m-%dT%H:%M:%fZ', 'now') WHERE id = ?
+`
+
+func (q *Queries) UpdateSessionTimestamp(ctx context.Context, id int64) error {
+    _, err := q.db.ExecContext(ctx, updateSessionTimestamp, id)
+    return err
+}
+
+const updateSessionTitle = `-- name: UpdateSessionTitle :exec
+UPDATE sessions SET title = ?, updated_at = strftime('%Y-%m-%dT%H:%M:%fZ', 'now') WHERE id = ?
+`
+
+type UpdateSessionTitleParams struct {
+    Title string `json:"title"`
+    ID    int64  `json:"id"`
+}
+
+func (q *Queries) UpdateSessionTitle(ctx context.Context, arg UpdateSessionTitleParams) error {
+    _, err := q.db.ExecContext(ctx, updateSessionTitle, arg.Title, arg.ID)
+    return err
+}

internal/db/sqlc.yaml

@@ -0,0 +1,11 @@
+version: "2"
+sql:
+  - engine: "sqlite"
+    queries: "queries"
+    schema: "migrations"
+    gen:
+      go:
+        package: "db"
+        out: "."
+        emit_json_tags: true
+        emit_empty_slices: true

internal/db/stats.sql.go

@@ -0,0 +1,216 @@
+// Code generated by sqlc. DO NOT EDIT.
+// versions:
+//   sqlc v1.30.0
+// source: stats.sql
+
+package db
+
+import (
+    "context"
+)
+
+const getSessionFileChangeSummary = `-- name: GetSessionFileChangeSummary :many
+SELECT
+    file_path,
+    CAST(COALESCE(SUM(added), 0) AS INTEGER) AS total_added,
+    CAST(COALESCE(SUM(removed), 0) AS INTEGER) AS total_removed,
+    CAST(COUNT(*) AS INTEGER) AS change_count
+FROM file_changes
+WHERE session_id = ?
+GROUP BY file_path
+ORDER BY file_path ASC
+`
+
+type GetSessionFileChangeSummaryRow struct {
+    FilePath     string `json:"file_path"`
+    TotalAdded   int64  `json:"total_added"`
+    TotalRemoved int64  `json:"total_removed"`
+    ChangeCount  int64  `json:"change_count"`
+}
+
+func (q *Queries) GetSessionFileChangeSummary(ctx context.Context, sessionID int64) ([]GetSessionFileChangeSummaryRow, error) {
+    rows, err := q.db.QueryContext(ctx, getSessionFileChangeSummary, sessionID)
+    if err != nil {
+        return nil, err
+    }
+    defer rows.Close()
+    items := []GetSessionFileChangeSummaryRow{}
+    for rows.Next() {
+        var i GetSessionFileChangeSummaryRow
+        if err := rows.Scan(
+            &i.FilePath,
+            &i.TotalAdded,
+            &i.TotalRemoved,
+            &i.ChangeCount,
+        ); err != nil {
+            return nil, err
+        }
+        items = append(items, i)
+    }
+    if err := rows.Close(); err != nil {
+        return nil, err
+    }
+    if err := rows.Err(); err != nil {
+        return nil, err
+    }
+    return items, nil
+}
+
+const getSessionFileChanges = `-- name: GetSessionFileChanges :many
+SELECT id, session_id, file_path, tool_name, added, removed, created_at FROM file_changes WHERE session_id = ? ORDER BY created_at ASC
+`
+
+func (q *Queries) GetSessionFileChanges(ctx context.Context, sessionID int64) ([]FileChange, error) {
+    rows, err := q.db.QueryContext(ctx, getSessionFileChanges, sessionID)
+    if err != nil {
+        return nil, err
+    }
+    defer rows.Close()
+    items := []FileChange{}
+    for rows.Next() {
+        var i FileChange
+        if err := rows.Scan(
+            &i.ID,
+            &i.SessionID,
+            &i.FilePath,
+            &i.ToolName,
+            &i.Added,
+            &i.Removed,
+            &i.CreatedAt,
+        ); err != nil {
+            return nil, err
+        }
+        items = append(items, i)
+    }
+    if err := rows.Close(); err != nil {
+        return nil, err
+    }
+    if err := rows.Err(); err != nil {
+        return nil, err
+    }
+    return items, nil
+}
+
+const getSessionTokenStats = `-- name: GetSessionTokenStats :many
+SELECT id, session_id, turn, eval_count, prompt_tokens, model, created_at FROM token_stats WHERE session_id = ? ORDER BY turn ASC
+`
+
+func (q *Queries) GetSessionTokenStats(ctx context.Context, sessionID int64) ([]TokenStat, error) {
+    rows, err := q.db.QueryContext(ctx, getSessionTokenStats, sessionID)
+    if err != nil {
+        return nil, err
+    }
+    defer rows.Close()
+    items := []TokenStat{}
+    for rows.Next() {
+        var i TokenStat
+        if err := rows.Scan(
+            &i.ID,
+            &i.SessionID,
+            &i.Turn,
+            &i.EvalCount,
+            &i.PromptTokens,
+            &i.Model,
+            &i.CreatedAt,
+        ); err != nil {
+            return nil, err
+        }
+        items = append(items, i)
+    }
+    if err := rows.Close(); err != nil {
+        return nil, err
+    }
+    if err := rows.Err(); err != nil {
+        return nil, err
+    }
+    return items, nil
+}
+
+const getSessionTotalTokens = `-- name: GetSessionTotalTokens :one
+SELECT
+    CAST(COALESCE(SUM(eval_count), 0) AS INTEGER) AS total_eval,
+    CAST(COALESCE(SUM(prompt_tokens), 0) AS INTEGER) AS total_prompt,
+    CAST(COUNT(*) AS INTEGER) AS turn_count
+FROM token_stats WHERE session_id = ?
+`
+
+type GetSessionTotalTokensRow struct {
+    TotalEval   int64 `json:"total_eval"`
+    TotalPrompt int64 `json:"total_prompt"`
+    TurnCount   int64 `json:"turn_count"`
+}
+
+func (q *Queries) GetSessionTotalTokens(ctx context.Context, sessionID int64) (GetSessionTotalTokensRow, error) {
+    row := q.db.QueryRowContext(ctx, getSessionTotalTokens, sessionID)
+    var i GetSessionTotalTokensRow
+    err := row.Scan(&i.TotalEval, &i.TotalPrompt, &i.TurnCount)
+    return i, err
+}
+
+const recordFileChange = `-- name: RecordFileChange :one
+INSERT INTO file_changes (session_id, file_path, tool_name, added, removed)
+VALUES (?, ?, ?, ?, ?) RETURNING id, session_id, file_path, tool_name, added, removed, created_at
+`
+
+type RecordFileChangeParams struct {
+    SessionID int64  `json:"session_id"`
+    FilePath  string `json:"file_path"`
+    ToolName  string `json:"tool_name"`
+    Added     int64  `json:"added"`
+    Removed   int64  `json:"removed"`
+}
+
+func (q *Queries) RecordFileChange(ctx context.Context, arg RecordFileChangeParams) (FileChange, error) {
+    row := q.db.QueryRowContext(ctx, recordFileChange,
+        arg.SessionID,
+        arg.FilePath,
+        arg.ToolName,
+        arg.Added,
+        arg.Removed,
+    )
+    var i FileChange
+    err := row.Scan(
+        &i.ID,
+        &i.SessionID,
+        &i.FilePath,
+        &i.ToolName,
+        &i.Added,
+        &i.Removed,
+        &i.CreatedAt,
+    )
+    return i, err
+}
+
+const recordTokenUsage = `-- name: RecordTokenUsage :one
+INSERT INTO token_stats (session_id, turn, eval_count, prompt_tokens, model)
+VALUES (?, ?, ?, ?, ?) RETURNING id, session_id, turn, eval_count, prompt_tokens, model, created_at
+`
+
+type RecordTokenUsageParams struct {
+    SessionID    int64  `json:"session_id"`
+    Turn         int64  `json:"turn"`
+    EvalCount    int64  `json:"eval_count"`
+    PromptTokens int64  `json:"prompt_tokens"`
+    Model        string `json:"model"`
+}
+
+func (q *Queries) RecordTokenUsage(ctx context.Context, arg RecordTokenUsageParams) (TokenStat, error) {
+    row := q.db.QueryRowContext(ctx, recordTokenUsage,
+        arg.SessionID,
+        arg.Turn,
+        arg.EvalCount,
+        arg.PromptTokens,
+        arg.Model,
+    )
+    var i TokenStat
+    err := row.Scan(
+        &i.ID,
+        &i.SessionID,
+        &i.Turn,
+        &i.EvalCount,
+        &i.PromptTokens,
+        &i.Model,
+        &i.CreatedAt,
+    )
+    return i, err
+}

internal/db/store.go

@@ -0,0 +1,71 @@
+package db
+
+import (
+    "database/sql"
+    "embed"
+    "fmt"
+    "os"
+    "path/filepath"
+
+    _ "modernc.org/sqlite"
+)
+
+//go:embed migrations/*.sql
+var migrations embed.FS
+
+type Store struct {
+    *Queries
+    db *sql.DB
+}
+
+func Open() (*Store, error) {
+    home, err := os.UserHomeDir()
+    if err != nil {
+        return nil, fmt.Errorf("home dir: %w", err)
+    }
+    dir := filepath.Join(home, ".config", "ai-agent")
+    if err := os.MkdirAll(dir, 0o755); err != nil {
+        return nil, fmt.Errorf("create config dir: %w", err)
+    }
+    return OpenPath(filepath.Join(dir, "ai-agent.db"))
+}
+
+func OpenPath(path string) (*Store, error) {
+    conn, err := sql.Open("sqlite", path+"?_journal_mode=WAL&_busy_timeout=5000&_foreign_keys=ON")
+    if err != nil {
+        return nil, fmt.Errorf("open db: %w", err)
+    }
+    if err := runMigrations(conn); err != nil {
+        conn.Close()
+        return nil, fmt.Errorf("migrations: %w", err)
+    }
+    return &Store{Queries: New(conn), db: conn}, nil
+}
+
+func (s *Store) Close() error {
+    return s.db.Close()
+}
+
+func (s *Store) DB() *sql.DB {
+    return s.db
+}
+
+func runMigrations(conn *sql.DB) error {
+    entries, err := migrations.ReadDir("migrations")
+    if err != nil {
+        return fmt.Errorf("read migrations dir: %w", err)
+    }
+    for _, entry := range entries {
+        if entry.IsDir() {
+            continue
+        }
+        data, err := migrations.ReadFile("migrations/" + entry.Name())
+        if err != nil {
+            return fmt.Errorf("read migration %s: %w", entry.Name(), err)
+        }
+        if _, err := conn.Exec(string(data)); err != nil {
+            return fmt.Errorf("exec migration %s: %w", entry.Name(), err)
+        }
+    }
+    return nil
+}

internal/db/store_test.go

@@ -0,0 +1,271 @@
+package db
+
+import (
+    "context"
+    "os"
+    "path/filepath"
+    "testing"
+)
+
+func testStore(t *testing.T) *Store {
+    t.Helper()
+    dir := t.TempDir()
+    s, err := OpenPath(filepath.Join(dir, "test.db"))
+    if err != nil {
+        t.Fatalf("open store: %v", err)
+    }
+    t.Cleanup(func() { s.Close() })
+    return s
+}
+
+func TestOpenAndMigrate(t *testing.T) {
+    s := testStore(t)
+    // Verify the store is functional by counting sessions.
+    ctx := context.Background()
+    count, err := s.CountSessions(ctx)
+    if err != nil {
+        t.Fatalf("count sessions: %v", err)
+    }
+    if count != 0 {
+        t.Fatalf("expected 0 sessions, got %d", count)
+    }
+}
+
+func TestSessionCRUD(t *testing.T) {
+    s := testStore(t)
+    ctx := context.Background()
+
+    // Create.
+    sess, err := s.CreateSession(ctx, CreateSessionParams{
+        Title: "Test Session",
+        Model: "qwen3.5:4b",
+        Mode:  "BUILD",
+    })
+    if err != nil {
+        t.Fatalf("create session: %v", err)
+    }
+    if sess.Title != "Test Session" {
+        t.Fatalf("expected title 'Test Session', got %q", sess.Title)
+    }
+
+    // Read.
+    got, err := s.GetSession(ctx, sess.ID)
+    if err != nil {
+        t.Fatalf("get session: %v", err)
+    }
+    if got.Model != "qwen3.5:4b" {
+        t.Fatalf("expected model 'qwen3.5:4b', got %q", got.Model)
+    }
+
+    // Create message.
+    msg, err := s.CreateSessionMessage(ctx, CreateSessionMessageParams{
+        SessionID: sess.ID,
+        Role:      "user",
+        Content:   "Hello world",
+    })
+    if err != nil {
+        t.Fatalf("create message: %v", err)
+    }
+    if msg.Content != "Hello world" {
+        t.Fatalf("expected content 'Hello world', got %q", msg.Content)
+    }
+
+    // List messages.
+    msgs, err := s.GetSessionMessages(ctx, sess.ID)
+    if err != nil {
+        t.Fatalf("get messages: %v", err)
+    }
+    if len(msgs) != 1 {
+        t.Fatalf("expected 1 message, got %d", len(msgs))
+    }
+
+    // Delete.
+    if err := s.DeleteSession(ctx, sess.ID); err != nil {
+        t.Fatalf("delete session: %v", err)
+    }
+    count, err := s.CountSessions(ctx)
+    if err != nil {
+        t.Fatalf("count: %v", err)
+    }
+    if count != 0 {
+        t.Fatalf("expected 0 after delete, got %d", count)
+    }
+}
+
+func TestToolPermissions(t *testing.T) {
+    s := testStore(t)
+    ctx := context.Background()
+
+    // Upsert.
+    perm, err := s.UpsertToolPermission(ctx, UpsertToolPermissionParams{
+        ToolName: "bash",
+        Policy:   "allow",
+    })
+    if err != nil {
+        t.Fatalf("upsert permission: %v", err)
+    }
+    if perm.Policy != "allow" {
+        t.Fatalf("expected policy 'allow', got %q", perm.Policy)
+    }
+
+    // Update via upsert.
+    perm2, err := s.UpsertToolPermission(ctx, UpsertToolPermissionParams{
+        ToolName: "bash",
+        Policy:   "deny",
+    })
+    if err != nil {
+        t.Fatalf("upsert update: %v", err)
+    }
+    if perm2.Policy != "deny" {
+        t.Fatalf("expected policy 'deny', got %q", perm2.Policy)
+    }
+
+    // List.
+    perms, err := s.ListToolPermissions(ctx)
+    if err != nil {
+        t.Fatalf("list permissions: %v", err)
+    }
+    if len(perms) != 1 {
+        t.Fatalf("expected 1 permission, got %d", len(perms))
+    }
+
+    // Reset.
+    if err := s.ResetToolPermissions(ctx); err != nil {
+        t.Fatalf("reset: %v", err)
+    }
+    perms, err = s.ListToolPermissions(ctx)
+    if err != nil {
+        t.Fatalf("list after reset: %v", err)
+    }
+    if len(perms) != 0 {
+        t.Fatalf("expected 0 after reset, got %d", len(perms))
+    }
+}
+
+func TestTokenStats(t *testing.T) {
+    s := testStore(t)
+    ctx := context.Background()
+
+    sess, err := s.CreateSession(ctx, CreateSessionParams{
+        Title: "Stats Test",
+        Model: "qwen3.5:4b",
+        Mode:  "ASK",
+    })
+    if err != nil {
+        t.Fatalf("create session: %v", err)
+    }
+
+    // Record usage.
+    _, err = s.RecordTokenUsage(ctx, RecordTokenUsageParams{
+        SessionID:    sess.ID,
+        Turn:         1,
+        EvalCount:    100,
+        PromptTokens: 500,
+        Model:        "qwen3.5:4b",
+    })
+    if err != nil {
+        t.Fatalf("record usage: %v", err)
+    }
+
+    _, err = s.RecordTokenUsage(ctx, RecordTokenUsageParams{
+        SessionID:    sess.ID,
+        Turn:         2,
+        EvalCount:    200,
+        PromptTokens: 600,
+        Model:        "qwen3.5:4b",
+    })
+    if err != nil {
+        t.Fatalf("record usage 2: %v", err)
+    }
+
+    // Get totals.
+    totals, err := s.GetSessionTotalTokens(ctx, sess.ID)
+    if err != nil {
+        t.Fatalf("get totals: %v", err)
+    }
+    if totals.TotalEval != 300 {
+        t.Fatalf("expected total_eval 300, got %v", totals.TotalEval)
+    }
+    if totals.TotalPrompt != 1100 {
+        t.Fatalf("expected total_prompt 1100, got %v", totals.TotalPrompt)
+    }
+    if totals.TurnCount != 2 {
+        t.Fatalf("expected turn_count 2, got %v", totals.TurnCount)
+    }
+}
+
+func TestFileChanges(t *testing.T) {
+    s := testStore(t)
+    ctx := context.Background()
+
+    sess, err := s.CreateSession(ctx, CreateSessionParams{
+        Title: "Changes Test",
+        Model: "qwen3.5:4b",
+        Mode:  "BUILD",
+    })
+    if err != nil {
+        t.Fatalf("create session: %v", err)
+    }
+
+    _, err = s.RecordFileChange(ctx, RecordFileChangeParams{
+        SessionID: sess.ID,
+        FilePath:  "main.go",
+        ToolName:  "write_file",
+        Added:     10,
+        Removed:   3,
+    })
+    if err != nil {
+        t.Fatalf("record change: %v", err)
+    }
+
+    _, err = s.RecordFileChange(ctx, RecordFileChangeParams{
+        SessionID: sess.ID,
+        FilePath:  "main.go",
+        ToolName:  "write_file",
+        Added:     5,
+        Removed:   2,
+    })
+    if err != nil {
+        t.Fatalf("record change 2: %v", err)
+    }
+
+    summary, err := s.GetSessionFileChangeSummary(ctx, sess.ID)
+    if err != nil {
+        t.Fatalf("get summary: %v", err)
+    }
+    if len(summary) != 1 {
+        t.Fatalf("expected 1 file, got %d", len(summary))
+    }
+    if summary[0].TotalAdded != 15 {
+        t.Fatalf("expected 15 added, got %d", summary[0].TotalAdded)
+    }
+}
+
+func TestDoubleOpen(t *testing.T) {
+    dir := t.TempDir()
+    path := filepath.Join(dir, "test.db")
+
+    s1, err := OpenPath(path)
+    if err != nil {
+        t.Fatalf("first open: %v", err)
+    }
+    defer s1.Close()
+
+    // Running migrations again should be idempotent (IF NOT EXISTS).
+    s2, err := OpenPath(path)
+    if err != nil {
+        t.Fatalf("second open: %v", err)
+    }
+    defer s2.Close()
+}
+
+func TestOpenDefault(t *testing.T) {
+    if os.Getenv("CI") != "" {
+        t.Skip("skip in CI to avoid side effects")
+    }
+    s, err := Open()
+    if err != nil {
+        t.Fatalf("open default: %v", err)
+    }
+    s.Close()
+}